Brief reversible episodes of focal, nonconvulsive ischemic dysfunction of the brain having a duration of less than 24 hours, and usually less than one hour, caused by transient thrombotic or embolic blood vessel occlusion or stenosis. Events may be classified by arterial distribution, temporal pattern, or etiology (e.g., embolic vs. thrombotic). (From Adams et al., Principles of Neurology, 6th ed, pp814-6)
A group of pathological conditions characterized by sudden, non-convulsive loss of neurological function due to BRAIN ISCHEMIA or INTRACRANIAL HEMORRHAGES. Stroke is classified by the type of tissue NECROSIS, such as the anatomic location, vasculature involved, etiology, age of the affected individual, and hemorrhagic vs. non-hemorrhagic nature. (From Adams et al., Principles of Neurology, 6th ed, pp777-810)
A spectrum of pathological conditions of impaired blood flow in the brain. They can involve vessels (ARTERIES or VEINS) in the CEREBRUM, the CEREBELLUM, and the BRAIN STEM. Major categories include INTRACRANIAL ARTERIOVENOUS MALFORMATIONS; BRAIN ISCHEMIA; CEREBRAL HEMORRHAGE; and others.
Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.
Narrowing or stricture of any part of the CAROTID ARTERIES, most often due to atherosclerotic plaque formation. Ulcerations may form in atherosclerotic plaques and induce THROMBUS formation. Platelet or cholesterol emboli may arise from stenotic carotid lesions and induce a TRANSIENT ISCHEMIC ATTACK; CEREBROVASCULAR ACCIDENT; or temporary blindness (AMAUROSIS FUGAX). (From Adams et al., Principles of Neurology, 6th ed, pp 822-3)
Pathological conditions involving the CAROTID ARTERIES, including the common, internal, and external carotid arteries. ATHEROSCLEROSIS and TRAUMA are relatively frequent causes of carotid artery pathology.
The excision of the thickened, atheromatous tunica intima of a carotid artery.
An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.
The formation of an area of NECROSIS in the CEREBRUM caused by an insufficiency of arterial or venous blood flow. Infarcts of the cerebrum are generally classified by hemisphere (i.e., left vs. right), lobe (e.g., frontal lobe infarction), arterial distribution (e.g., INFARCTION, ANTERIOR CEREBRAL ARTERY), and etiology (e.g., embolic infarction).
Elements of limited time intervals, contributing to particular results or situations.
The return of a sign, symptom, or disease after a remission.
Surgical excision, performed under general anesthesia, of the atheromatous tunica intima of an artery. When reconstruction of an artery is performed as an endovascular procedure through a catheter, it is called ATHERECTOMY.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
Vascular diseases characterized by thickening and hardening of the walls of ARTERIES inside the SKULL. There are three subtypes: (1) atherosclerosis with fatty deposits in the ARTERIAL INTIMA; (2) Monckeberg's sclerosis with calcium deposits in the media and (3) arteriolosclerosis involving the small caliber arteries. Clinical signs include HEADACHE; CONFUSION; transient blindness (AMAUROSIS FUGAX); speech impairment; and HEMIPARESIS.
Radiography of the vascular system of the brain after injection of a contrast medium.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Blocking of a blood vessel in the SKULL by an EMBOLUS which can be a blood clot (THROMBUS) or other undissolved material in the blood stream. Most emboli are of cardiac origin and are associated with HEART DISEASES. Other non-cardiac sources of emboli are usually associated with VASCULAR DISEASES.
Branch of the common carotid artery which supplies the anterior part of the brain, the eye and its appendages, the forehead and nose.
Pathological conditions involving ARTERIES in the skull, such as arteries supplying the CEREBRUM, the CEREBELLUM, the BRAIN STEM, and associated structures. They include atherosclerotic, congenital, traumatic, infectious, inflammatory, and other pathological processes.
A medical specialty concerned with the study of the structures, functions, and diseases of the nervous system.
Embolism or thrombosis involving blood vessels which supply intracranial structures. Emboli may originate from extracranial or intracranial sources. Thrombosis may occur in arterial or venous structures.
A noninflammatory, progressive occlusion of the intracranial CAROTID ARTERIES and the formation of netlike collateral arteries arising from the CIRCLE OF WILLIS. Cerebral angiogram shows the puff-of-smoke (moyamoya) collaterals at the base of the brain. It is characterized by endothelial HYPERPLASIA and FIBROSIS with thickening of arterial walls. This disease primarily affects children but can also occur in adults.
The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. (From Martindale, The Extra Pharmacopoeia, 30th ed, p5)
Either of the two principal arteries on both sides of the neck that supply blood to the head and neck; each divides into two branches, the internal carotid artery and the external carotid artery.
Transient complete or partial monocular blindness due to retinal ischemia. This may be caused by emboli from the CAROTID ARTERY (usually in association with CAROTID STENOSIS) and other locations that enter the central RETINAL ARTERY. (From Adams et al., Principles of Neurology, 6th ed, p245)
Blocking of a blood vessel by an embolus which can be a blood clot or other undissolved material in the blood stream.
Localized or diffuse reduction in blood flow through the vertebrobasilar arterial system, which supplies the BRAIN STEM; CEREBELLUM; OCCIPITAL LOBE; medial TEMPORAL LOBE; and THALAMUS. Characteristic clinical features include SYNCOPE; lightheadedness; visual disturbances; and VERTIGO. BRAIN STEM INFARCTIONS or other BRAIN INFARCTION may be associated.
The prevention of recurrences or exacerbations of a disease or complications of its therapy.
Agents that prevent clotting.
Drugs or agents which antagonize or impair any mechanism leading to blood platelet aggregation, whether during the phases of activation and shape change or following the dense-granule release reaction and stimulation of the prostaglandin-thromboxane system.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.
Bleeding into one or both CEREBRAL HEMISPHERES including the BASAL GANGLIA and the CEREBRAL CORTEX. It is often associated with HYPERTENSION and CRANIOCEREBRAL TRAUMA.
NECROSIS induced by ISCHEMIA in the POSTERIOR CEREBRAL ARTERY distribution system which supplies portions of the BRAIN STEM; the THALAMUS; TEMPORAL LOBE, and OCCIPITAL LOBE. Depending on the size and location of infarction, clinical features include OLFACTION DISORDERS and visual problems (AGNOSIA; ALEXIA; HEMIANOPSIA).
A class of disabling primary headache disorders, characterized by recurrent unilateral pulsatile headaches. The two major subtypes are common migraine (without aura) and classic migraine (with aura or neurological symptoms). (International Classification of Headache Disorders, 2nd ed. Cephalalgia 2004: suppl 1)
The arterial blood vessels supplying the CEREBRUM.
Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.
Non-invasive method of vascular imaging and determination of internal anatomy without injection of contrast media or radiation exposure. The technique is used especially in CEREBRAL ANGIOGRAPHY as well as for studies of other vascular structures.
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
The circulation of blood through the BLOOD VESSELS of the BRAIN.
A condition in which the FORAMEN OVALE in the ATRIAL SEPTUM fails to close shortly after birth. This results in abnormal communications between the two upper chambers of the heart. An isolated patent ovale foramen without other structural heart defects is usually of no hemodynamic significance.
The probability that an event will occur. It encompasses a variety of measures of the probability of a generally unfavorable outcome.
A uricosuric drug that is used to reduce the serum urate levels in gout therapy. It lacks anti-inflammatory, analgesic, and diuretic properties.
Services specifically designed, staffed, and equipped for the emergency care of patients.
A diagnostic technique that incorporates the measurement of molecular diffusion (such as water or metabolites) for tissue assessment by MRI. The degree of molecular movement can be measured by changes of apparent diffusion coefficient (ADC) with time, as reflected by tissue microstructure. Diffusion MRI has been used to study BRAIN ISCHEMIA and tumor response to treatment.
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide.
The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)
A reflex found in normal infants consisting of dorsiflexion of the HALLUX and abduction of the other TOES in response to cutaneous stimulation of the plantar surface of the FOOT. In adults, it is used as a diagnostic criterion, and if present is a NEUROLOGIC MANIFESTATION of dysfunction in the CENTRAL NERVOUS SYSTEM.
Act of listening for sounds within the body.
A non-invasive technique using ultrasound for the measurement of cerebrovascular hemodynamics, particularly cerebral blood flow velocity and cerebral collateral flow. With a high-intensity, low-frequency pulse probe, the intracranial arteries may be studied transtemporally, transorbitally, or from below the foramen magnum.
Pathological processes which result in the partial or complete obstruction of ARTERIES. They are characterized by greatly reduced or absence of blood flow through these vessels. They are also known as arterial insufficiency.
Microsurgical revascularization to improve intracranial circulation. It usually involves joining the extracranial circulation to the intracranial circulation but may include extracranial revascularization (e.g., subclavian-vertebral artery bypass, subclavian-external carotid artery bypass). It is performed by joining two arteries (direct anastomosis or use of graft) or by free autologous transplantation of highly vascularized tissue to the surface of the brain.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.
Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.
A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. It is formed by the sequential assembly of terminal complement components (COMPLEMENT C5B; COMPLEMENT C6; COMPLEMENT C7; COMPLEMENT C8; and COMPLEMENT C9) into the target membrane. The resultant C5b-8-poly-C9 is the "membrane attack complex" or MAC.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
Radiography of blood vessels after injection of a contrast medium.
Bleeding within the SKULL, including hemorrhages in the brain and the three membranes of MENINGES. The escape of blood often leads to the formation of HEMATOMA in the cranial epidural, subdural, and subarachnoid spaces.
The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.
Blood clot formation in any part of the CAROTID ARTERIES. This may produce CAROTID STENOSIS or occlusion of the vessel, leading to TRANSIENT ISCHEMIC ATTACK; CEREBRAL INFARCTION; or AMAUROSIS FUGAX.
Devices that provide support for tubular structures that are being anastomosed or for body cavities during skin grafting.
Reconstruction or repair of a blood vessel, which includes the widening of a pathological narrowing of an artery or vein by the removal of atheromatous plaque material and/or the endothelial lining as well, or by dilatation (BALLOON ANGIOPLASTY) to compress an ATHEROMA. Except for ENDARTERECTOMY, usually these procedures are performed via catheterization as minimally invasive ENDOVASCULAR PROCEDURES.
An effective inhibitor of platelet aggregation commonly used in the placement of STENTS in CORONARY ARTERIES.
Assessment of sensory and motor responses and reflexes that is used to determine impairment of the nervous system.
Ultrasonography applying the Doppler effect combined with real-time imaging. The real-time image is created by rapid movement of the ultrasound beam. A powerful advantage of this technique is the ability to estimate the velocity of flow from the Doppler shift frequency.
Formation or presence of a blood clot (THROMBUS) in a blood vessel within the SKULL. Intracranial thrombosis can lead to thrombotic occlusions and BRAIN INFARCTION. The majority of the thrombotic occlusions are associated with ATHEROSCLEROSIS.
Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.
Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.
Disease having a short and relatively severe course.
A phosphodiesterase inhibitor that blocks uptake and metabolism of adenosine by erythrocytes and vascular endothelial cells. Dipyridamole also potentiates the antiaggregating action of prostacyclin. (From AMA Drug Evaluations Annual, 1994, p752)
The systems and processes involved in the establishment, support, management, and operation of registers, e.g., disease registers.
The condition of an anatomical structure's being constricted beyond normal dimensions.
Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.
The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of EYE DISEASES; OPTIC NERVE DISEASES; OPTIC CHIASM diseases; or BRAIN DISEASES affecting the VISUAL PATHWAYS or OCCIPITAL LOBE.
A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.
Pathological processes involving any of the BLOOD VESSELS in the cardiac or peripheral circulation. They include diseases of ARTERIES; VEINS; and rest of the vasculature system in the body.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Tissue NECROSIS in any area of the brain, including the CEREBRAL HEMISPHERES, the CEREBELLUM, and the BRAIN STEM. Brain infarction is the result of a cascade of events initiated by inadequate blood flow through the brain that is followed by HYPOXIA and HYPOGLYCEMIA in brain tissue. Damage may be temporary, permanent, selective or pan-necrosis.
Terrorism on September 11, 2001 against targets in New York, the Pentagon in Virginia, and an aborted attack that ended in Pennsylvania.
Pathological conditions involving the HEART including its structural and functional abnormalities.
The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1.6 to 10 megahertz.
An idiopathic, segmental, nonatheromatous disease of the musculature of arterial walls, leading to STENOSIS of small and medium-sized arteries. There is true proliferation of SMOOTH MUSCLE CELLS and fibrous tissue. Fibromuscular dysplasia lesions are smooth stenosis and occur most often in the renal and carotid arteries. They may also occur in other peripheral arteries of the extremity.
Obstruction of a blood vessel (embolism) by a blood clot (THROMBUS) in the blood stream.
Blockage of an artery due to passage of a clot (THROMBUS) from a systemic vein to a systemic artery without its passing through the lung which acts as a filter to remove blood clots from entering the arterial circulation. Paradoxical embolism occurs when there is a defect that allows a clot to cross directly from the right to the left side of the heart as in the cases of ATRIAL SEPTAL DEFECTS or open FORAMEN OVALE. Once in the arterial circulation, a clot can travel to the brain, block an artery, and cause a STROKE.
Fibrinolysin or agents that convert plasminogen to FIBRINOLYSIN.
Use of a balloon catheter for dilation of an occluded artery. It is used in treatment of arterial occlusive diseases, including renal artery stenosis and arterial occlusions in the leg. For the specific technique of BALLOON DILATION in coronary arteries, ANGIOPLASTY, BALLOON, CORONARY is available.
The sorting out and classification of patients or casualties to determine priority of need and proper place of treatment.
Measurement of the blood pressure of the retinal vessels. It is used also for the determination of the near point of convergence (CONVERGENCE, OCULAR). (From Cline, et al., Dictionary of Visual Science, 4th ed)
Thickening and loss of elasticity of the walls of ARTERIES of all sizes. There are many forms classified by the types of lesions and arteries involved, such as ATHEROSCLEROSIS with fatty lesions in the ARTERIAL INTIMA of medium and large muscular arteries.
The first branch of the SUBCLAVIAN ARTERY with distribution to muscles of the NECK; VERTEBRAE; SPINAL CORD; CEREBELLUM; and interior of the CEREBRUM.
NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).
The use or threatened use of force or violence against persons or property in violation of criminal laws for purposes of intimidation, coercion, or ransom, in support of political or social objectives.
Maleness or femaleness as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or effect of a circumstance. It is used with human or animal concepts but should be differentiated from SEX CHARACTERISTICS, anatomical or physiological manifestations of sex, and from SEX DISTRIBUTION, the number of males and females in given circumstances.
Abnormal protrusion or billowing of one or both of the leaflets of MITRAL VALVE into the LEFT ATRIUM during SYSTOLE. This allows the backflow of blood into left atrium leading to MITRAL VALVE INSUFFICIENCY; SYSTOLIC MURMURS; or CARDIAC ARRHYTHMIA.
Conditions or pathological processes associated with the disease of diabetes mellitus. Due to the impaired control of BLOOD GLUCOSE level in diabetic patients, pathological processes develop in numerous tissues and organs including the EYE, the KIDNEY, the BLOOD VESSELS, and the NERVE TISSUE.
Ear-shaped appendage of either atrium of the heart. (Dorland, 28th ed)
One of the CARBONIC ANHYDRASE INHIBITORS that is sometimes effective against absence seizures. It is sometimes useful also as an adjunct in the treatment of tonic-clonic, myoclonic, and atonic seizures, particularly in women whose seizures occur or are exacerbated at specific times in the menstrual cycle. However, its usefulness is transient often because of rapid development of tolerance. Its antiepileptic effect may be due to its inhibitory effect on brain carbonic anhydrase, which leads to an increased transneuronal chloride gradient, increased chloride current, and increased inhibition. (From Smith and Reynard, Textbook of Pharmacology, 1991, p337)
The symptom of PAIN in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of HEADACHE DISORDERS.
The ratio of two odds. The exposure-odds ratio for case control data is the ratio of the odds in favor of exposure among cases to the odds in favor of exposure among noncases. The disease-odds ratio for a cohort or cross section is the ratio of the odds in favor of disease among the exposed to the odds in favor of disease among the unexposed. The prevalence-odds ratio refers to an odds ratio derived cross-sectionally from studies of prevalent cases.
Polyester polymers formed from terephthalic acid or its esters and ethylene glycol. They can be formed into tapes, films or pulled into fibers that are pressed into meshes or woven into fabrics.
I'm sorry for any confusion, but "Berlin" is not a medical term or concept to the best of my knowledge and searching through medical resources. It's actually the capital city of Germany, known for its rich history, diverse architecture, vibrant culture, and significant landmarks such as the Berlin Wall and Brandenburg Gate.
A general term referring to a mild to moderate degree of muscular weakness, occasionally used as a synonym for PARALYSIS (severe or complete loss of motor function). In the older literature, paresis often referred specifically to paretic neurosyphilis (see NEUROSYPHILIS). "General paresis" and "general paralysis" may still carry that connotation. Bilateral lower extremity paresis is referred to as PARAPARESIS.
Unstable isotopes of xenon that decay or disintegrate emitting radiation. Xe atoms with atomic weights 121-123, 125, 127, 133, 135, 137-145 are radioactive xenon isotopes.
A group of water-soluble vitamins, some of which are COENZYMES.
A set of techniques used when variation in several variables has to be studied simultaneously. In statistics, multivariate analysis is interpreted as any analytic method that allows simultaneous study of two or more dependent variables.
Branch of the common carotid artery which supplies the exterior of the head, the face, and the greater part of the neck.
Works about clinical trials that involve at least one test treatment and one control treatment, concurrent enrollment and follow-up of the test- and control-treated groups, and in which the treatments to be administered are selected by a random process, such as the use of a random-numbers table.
Bleeding or escape of blood from a vessel.
Statistical models used in survival analysis that assert that the effect of the study factors on the hazard rate in the study population is multiplicative and does not change over time.
An imprecise term which may refer to a sense of spatial disorientation, motion of the environment, or lightheadedness.
Methods to determine in patients the nature of a disease or disorder at its early stage of progression. Generally, early diagnosis improves PROGNOSIS and TREATMENT OUTCOME.
Diseases of the central and peripheral nervous system. This includes disorders of the brain, spinal cord, cranial nerves, peripheral nerves, nerve roots, autonomic nervous system, neuromuscular junction, and muscle.
A type of MAGNETIC RESONANCE IMAGING that uses only one nuclear spin excitation per image and therefore can obtain images in a fraction of a second rather than the minutes required in traditional MRI techniques. It is used in a variety of medical and scientific applications.
Complications that affect patients during surgery. They may or may not be associated with the disease for which the surgery is done, or within the same surgical procedure.
Developmental abnormalities in any portion of the ATRIAL SEPTUM resulting in abnormal communications between the two upper chambers of the heart. Classification of atrial septal defects is based on location of the communication and types of incomplete fusion of atrial septa with the ENDOCARDIAL CUSHIONS in the fetal heart. They include ostium primum, ostium secundum, sinus venosus, and coronary sinus defects.
Artificial substitutes for body parts, and materials inserted into tissue for functional, cosmetic, or therapeutic purposes. Prostheses can be functional, as in the case of artificial arms and legs, or cosmetic, as in the case of an artificial eye. Implants, all surgically inserted or grafted into the body, tend to be used therapeutically. IMPLANTS, EXPERIMENTAL is available for those used experimentally.
The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.
Pathological conditions of intracranial ARTERIES supplying the CEREBRUM. These diseases often are due to abnormalities or pathological processes in the ANTERIOR CEREBRAL ARTERY; MIDDLE CEREBRAL ARTERY; and POSTERIOR CEREBRAL ARTERY.
Laboratory tests demonstrating the presence of physiologically significant substances in the blood, urine, tissue, and body fluids with application to the diagnosis or therapy of disease.
The largest of the cerebral arteries. It trifurcates into temporal, frontal, and parietal branches supplying blood to most of the parenchyma of these lobes in the CEREBRAL CORTEX. These are the areas involved in motor, sensory, and speech activities.
The splitting of the vessel wall in one or both (left and right) internal carotid arteries (CAROTID ARTERY, INTERNAL). Interstitial hemorrhage into the media of the vessel wall can lead to occlusion of the internal carotid artery and aneurysm formation.
The two principal arteries supplying the structures of the head and neck. They ascend in the neck, one on each side, and at the level of the upper border of the thyroid cartilage, each divides into two branches, the external (CAROTID ARTERY, EXTERNAL) and internal (CAROTID ARTERY, INTERNAL) carotid arteries.
A broad group of eukaryotic six-transmembrane cation channels that are classified by sequence homology because their functional involvement with SENSATION is varied. They have only weak voltage sensitivity and ion selectivity. They are named after a DROSOPHILA mutant that displayed transient receptor potentials in response to light. A 25-amino-acid motif containing a TRP box (EWKFAR) just C-terminal to S6 is found in TRPC, TRPV and TRPM subgroups. ANKYRIN repeats are found in TRPC, TRPV & TRPN subgroups. Some are functionally associated with TYROSINE KINASE or TYPE C PHOSPHOLIPASES.
The term "United States" in a medical context often refers to the country where a patient or study participant resides, and is not a medical term per se, but relevant for epidemiological studies, healthcare policies, and understanding differences in disease prevalence, treatment patterns, and health outcomes across various geographic locations.
Therapy with two or more separate preparations given for a combined effect.
A cognitive disorder marked by an impaired ability to comprehend or express language in its written or spoken form. This condition is caused by diseases which affect the language areas of the dominant hemisphere. Clinical features are used to classify the various subtypes of this condition. General categories include receptive, expressive, and mixed forms of aphasia.
Compilations of data on hospital activities and programs; excludes patient medical records.
A class of statistical procedures for estimating the survival function (function of time, starting with a population 100% well at a given time and providing the percentage of the population still well at later times). The survival analysis is then used for making inferences about the effects of treatments, prognostic factors, exposures, and other covariates on the function.
Statistical models which describe the relationship between a qualitative dependent variable (that is, one which can take only certain discrete values, such as the presence or absence of a disease) and an independent variable. A common application is in epidemiology for estimating an individual's risk (probability of a disease) as a function of a given risk factor.
Dysfunction of one or more cranial nerves causally related to a traumatic injury. Penetrating and nonpenetrating CRANIOCEREBRAL TRAUMA; NECK INJURIES; and trauma to the facial region are conditions associated with cranial nerve injuries.
Non-invasive methods of visualizing the CENTRAL NERVOUS SYSTEM, especially the brain, by various imaging modalities.
The confinement of a patient in a hospital.
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
The artery formed by the union of the right and left vertebral arteries; it runs from the lower to the upper border of the pons, where it bifurcates into the two posterior cerebral arteries.
A visual symptom in which a single object is perceived by the visual cortex as two objects rather than one. Disorders associated with this condition include REFRACTIVE ERRORS; STRABISMUS; OCULOMOTOR NERVE DISEASES; TROCHLEAR NERVE DISEASES; ABDUCENS NERVE DISEASES; and diseases of the BRAIN STEM and OCCIPITAL LOBE.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Formation and development of a thrombus or blood clot in the blood vessel.
Laboratory examination used to monitor and evaluate platelet function in a patient's blood.
Works about pre-planned studies of the safety, efficacy, or optimum dosage schedule (if appropriate) of one or more diagnostic, therapeutic, or prophylactic drugs, devices, or techniques selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects. This concept includes clinical trials conducted both in the U.S. and in other countries.
A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.
The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.
A polygonal anastomosis at the base of the brain formed by the internal carotid (CAROTID ARTERY, INTERNAL), proximal parts of the anterior, middle, and posterior cerebral arteries (ANTERIOR CEREBRAL ARTERY; MIDDLE CEREBRAL ARTERY; POSTERIOR CEREBRAL ARTERY), the anterior communicating artery and the posterior communicating arteries.
A syndrome characterized by a transient loss of the ability to form new memories. It primarily occurs in middle aged or elderly individuals, and episodes may last from minutes to hours. During the period of amnesia, immediate and recent memory abilities are impaired, but the level of consciousness and ability to perform other intellectual tasks are preserved. The condition is related to bilateral dysfunction of the medial portions of each TEMPORAL LOBE. Complete recovery normally occurs, and recurrences are unusual. (From Adams et al., Principles of Neurology, 6th ed, pp429-30)
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
The rate dynamics in chemical or physical systems.
Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS.
Bleeding into the intracranial or spinal SUBARACHNOID SPACE, most resulting from INTRACRANIAL ANEURYSM rupture. It can occur after traumatic injuries (SUBARACHNOID HEMORRHAGE, TRAUMATIC). Clinical features include HEADACHE; NAUSEA; VOMITING, nuchal rigidity, variable neurological deficits and reduced mental status.
A technique in which tissue is rendered resistant to the deleterious effects of prolonged ISCHEMIA and REPERFUSION by prior exposure to brief, repeated periods of vascular occlusion. (Am J Physiol 1995 May;268(5 Pt 2):H2063-7, Abstract)
Abnormal outpouching in the wall of intracranial blood vessels. Most common are the saccular (berry) aneurysms located at branch points in CIRCLE OF WILLIS at the base of the brain. Vessel rupture results in SUBARACHNOID HEMORRHAGE or INTRACRANIAL HEMORRHAGES. Giant aneurysms (>2.5 cm in diameter) may compress adjacent structures, including the OCULOMOTOR NERVE. (From Adams et al., Principles of Neurology, 6th ed, p841)
Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.
Hospital department responsible for the administration and provision of immediate medical or surgical care to the emergency patient.
A heterogeneous group of disorders characterized by HYPERGLYCEMIA and GLUCOSE INTOLERANCE.
A method of delineating blood vessels by subtracting a tissue background image from an image of tissue plus intravascular contrast material that attenuates the X-ray photons. The background image is determined from a digitized image taken a few moments before injection of the contrast material. The resulting angiogram is a high-contrast image of the vessel. This subtraction technique allows extraction of a high-intensity signal from the superimposed background information. The image is thus the result of the differential absorption of X-rays by different tissues.
Pathological conditions involving the CARDIOVASCULAR SYSTEM including the HEART; the BLOOD VESSELS; or the PERICARDIUM.
Human alloantigens expressed only on platelets, specifically on platelet membrane glycoproteins. These platelet-specific antigens are immunogenic and can result in pathological reactions to transfusion therapy.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
NECROSIS occurring in the MIDDLE CEREBRAL ARTERY distribution system which brings blood to the entire lateral aspects of each CEREBRAL HEMISPHERE. Clinical signs include impaired cognition; APHASIA; AGRAPHIA; weak and numbness in the face and arms, contralaterally or bilaterally depending on the infarction.
Compounds that inhibit HMG-CoA reductases. They have been shown to directly lower cholesterol synthesis.
Inhaling and exhaling the smoke of burning TOBACCO.
Studies to determine the advantages or disadvantages, practicability, or capability of accomplishing a projected plan, study, or project.
A thickening and loss of elasticity of the walls of ARTERIES that occurs with formation of ATHEROSCLEROTIC PLAQUES within the ARTERIAL INTIMA.
Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.
The part of a human or animal body connecting the HEAD to the rest of the body.
Summarizing techniques used to describe the pattern of mortality and survival in populations. These methods can be applied to the study not only of death, but also of any defined endpoint such as the onset of disease or the occurrence of disease complications.
Extensive collections, reputedly complete, of facts and data garnered from material of a specialized subject area and made available for analysis and application. The collection can be automated by various contemporary methods for retrieval. The concept should be differentiated from DATABASES, BIBLIOGRAPHIC which is restricted to collections of bibliographic references.
Works about controlled studies which are planned and carried out by several cooperating institutions to assess certain variables and outcomes in specific patient populations, for example, a multicenter study of congenital anomalies in children.
A type of anxiety disorder characterized by unexpected panic attacks that last minutes or, rarely, hours. Panic attacks begin with intense apprehension, fear or terror and, often, a feeling of impending doom. Symptoms experienced during a panic attack include dyspnea or sensations of being smothered; dizziness, loss of balance or faintness; choking sensations; palpitations or accelerated heart rate; shakiness; sweating; nausea or other form of abdominal distress; depersonalization or derealization; paresthesias; hot flashes or chills; chest discomfort or pain; fear of dying and fear of not being in control of oneself or going crazy. Agoraphobia may also develop. Similar to other anxiety disorders, it may be inherited as an autosomal dominant trait.
A disorder of HEMOSTASIS in which there is a tendency for the occurrence of THROMBOSIS.
A CATHETER-delivered implant used for closing abnormal holes in the cardiovascular system, especially HEART SEPTAL DEFECTS; or passageways intentionally made during cardiovascular surgical procedures.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Establishment of the level of a quantifiable effect indicative of a biologic process. The evaluation is frequently to detect the degree of toxic or therapeutic effect.
Persons who receive ambulatory care at an outpatient department or clinic without room and board being provided.
Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.

Synergistic protective effects of antioxidant and nitric oxide synthase inhibitor in transient focal ischemia. (1/2940)

Both nitric oxide synthase (NOS) inhibitors and free radical scavengers have been shown to protect brain tissue in ischemia-reperfusion injury. Nitric oxide and superoxide anion act via distinct mechanisms and react together to form the highly deleterious peroxynitrite. Therefore the authors examined the effects and the interaction between the NOS inhibitor, NG nitro-L-arginine (LNA) and the antioxidant/superoxide scavenger, di-tert-butyl-hydroxybenzoic acid (DtBHB) in the rat submitted to 2 hours of middle cerebral artery occlusion. Posttreatment was initiated 4 hours after the onset of ischemia and infarct volume was measured at 48 hours. The dose-related effect of LNA resulted in a bell-shaped curve: 15, 56, 65, and 33% reduction of total infarct for 0.03, 0.1, 0.3, and 1 mg/kg (intravenously [IV]) respectively and 11% increase in infarct volume for 3 mg/kg (IV). Whereas DtBHB (20 mg/kg; intraperitoneally [IP]) was ineffective, the dose of 60 mg/kg produced 65% protection in infarct volume. The combination of a subthreshold dose of LNA (0.03 mg/kg; IV) and DtBHB (20 mg/kg; IP) resulted in significant reduction (49%) in infarct volume. These results show that LNA and DtBHB act synergistically to provide a consistent neuroprotection against ischemic injury when administered 4 hours after ischemia. This suggests that nitric oxide and free radicals are involved and interact in synergy in ischemia-reperfusion injury.  (+info)

Changes in protein tyrosine phosphorylation in the rat brain after cerebral ischemia in a model of ischemic tolerance. (2/2940)

A brief period of sublethal cerebral ischemia, followed by several days of recovery, renders the brain resistant to a subsequent lethal ischemic insult, a phenomenon termed ischemic preconditioning or tolerance. Ischemic tolerance was established in the rat two-vessel occlusion model of ischemia, induced by occlusion of both carotid arteries in combination with hypotension. Ischemic preconditioning (3 minutes) provided maximal neuroprotection when induced 2 days prior to a lethal ischemic insult of 9-minute duration. Neuroprotection persisted for at least 8 weeks. Since neurotransmission has been implicated in ischemic cell death, the effect of ischemic preconditioning on tyrosine phosphorylation of proteins and on the levels of glutamate receptor subunits in hippocampus and neocortex was studied. Regional levels of tyrosine phosphorylation of proteins in general and the N-methyl-D-aspartate receptor subunit NR2 in particular are markedly enhanced after ischemia in nonconditioned brains, in both the synaptosomal fraction and the whole-tissue homogenate of rat neocortex and hippocampus, but recover to control levels only in the preconditioned brain. Ischemic preconditioning selectively induces a decrease in the levels of the NR2A and NR2B subunits and a modest decrease in the levels of NR1 subunit proteins in the synaptosomal fraction of the neocortex but not hippocampus after the second lethal ischemia. It was concluded that ischemic preconditioning prevents a persistent change in cell signaling as evidenced by the tyrosine phosphorylation of proteins after the second lethal ischemic insult, which may abrogate the activation of detrimental cellular processes leading to cell death.  (+info)

Combination therapy of fasudil hydrochloride and ozagrel sodium for cerebral vasospasm following aneurysmal subarachnoid hemorrhage. (3/2940)

Fasudil hydrochloride is a new type of intracellular calcium antagonist, different from the calcium entry blockers that are commonly employed for clinical use. Since September 1995, the combination of fasudil hydrochloride and ozagrel sodium, an inhibitor of thromboxane A2 synthesis, has been used to treat 60 patients at risk of cerebral vasospasm after aneurysmal subarachnoid hemorrhage. The effectiveness of this combination therapy was investigated by comparison with the outcome of 57 patients previously treated with only ozagrel sodium. The combination therapy was significantly more effective (p < 0.01) in reducing the incidence of low density areas on computed tomography scans, and reduced, but not significantly, the occurrence of symptomatic vasospasm. The combination therapy of fasudil hydrochloride and ozagrel sodium has superior effectiveness over only ozagrel sodium in treating patients at risk of vasospasm after aneurysmal subarachnoid hemorrhage.  (+info)

Modification of postsynaptic densities after transient cerebral ischemia: a quantitative and three-dimensional ultrastructural study. (4/2940)

Abnormal synaptic transmission has been hypothesized to be a cause of neuronal death resulting from transient ischemia, although the mechanisms are not fully understood. Here, we present evidence that synapses are markedly modified in the hippocampus after transient cerebral ischemia. Using both conventional and high-voltage electron microscopy, we performed two- and three-dimensional analyses of synapses selectively stained with ethanolic phosphotungstic acid in the hippocampus of rats subjected to 15 min of ischemia followed by various periods of reperfusion. Postsynaptic densities (PSDs) from both area CA1 and the dentate gyrus were thicker and fluffier in postischemic hippocampus than in controls. Three-dimensional reconstructions of selectively stained PSDs created using electron tomography indicated that postsynaptic densities became more irregular and loosely configured in postischemic brains compared with those in controls. A quantitative study based on thin sections of the time course of PSD modification indicated that the increase in thickness was both greater and more long-lived in area CA1 than in dentate gyrus. Whereas the magnitude of morphological change in dentate gyrus peaked at 4 hr of reperfusion (140% of control values) and declined thereafter, changes in area CA1 persisted and increased at 24 hr of reperfusion (191% of control values). We hypothesize that the degenerative ultrastructural alteration of PSDs may produce a toxic signal such as a greater calcium influx, which is integrated from the thousands of excitatory synapses onto dendrites, and is propagated to the neuronal somata where it causes or contributes to neuronal damage during the postischemic phase.  (+info)

Outcome of carotid artery occlusion is predicted by cerebrovascular reactivity. (5/2940)

BACKGROUND AND PURPOSE: The purpose of this study was to investigate the possibility of obtaining prognostic indications in patients with internal carotid occlusion on the basis of intracranial hemodynamic status, presence of previous symptoms of cerebrovascular failure, and baseline characteristics. METHODS: Cerebral hemodynamics were studied with transcranial Doppler ultrasonography. Cerebrovascular reactivity to apnea was calculated by means of the breath-holding index (BHI) in the middle cerebral arteries. Sixty-five patients with internal carotid artery occlusion were followed-up prospectively (median, 24 months), 23 patients were asymptomatic and 42 symptomatic (20 with transient ischemic attack and 22 with stroke). RESULTS: During the follow-up period, 11 symptomatic patients and 1 asymptomatic patient had another ischemic event ipsilateral to carotid occlusion. Among factors considered, only lower BHI values in the middle cerebral arteries ipsilateral to carotid occlusion and older age were significantly associated with the risk of developing symptoms (P=0.002 and P=0.003, respectively; Cox regression multivariate analysis). Based on our data, a cut point of the BHI value for distinguishing between pathological and normal cerebrovascular reactivity was determined to be 0.69. All patients except one, who developed TIA or stroke during the follow-up period, had BHI values ipsilateral to carotid occlusion of <0.69. CONCLUSIONS: These data suggest that impaired cerebrovascular reactivity is predictive for cerebral ischemic events in patients with carotid occlusion.  (+info)

Diffusion- and perfusion-weighted imaging in vasospasm after subarachnoid hemorrhage. (6/2940)

BACKGROUND AND PURPOSE: Better measures of cerebral tissue perfusion and earlier detection of ischemic injury are needed to guide therapy in subarachnoid hemorrhage (SAH) patients with vasospasm. We sought to identify tissue ischemia and early ischemic injury with combined diffusion-weighted (DW) and hemodynamically weighted (HW) MRI in patients with vasospasm after SAH. METHODS: Combined DW and HW imaging was used to study 6 patients with clinical and angiographic vasospasm, 1 patient without clinical signs of vasospasm but with severe angiographic vasospasm, and 1 patient without angiographic spasm. Analysis of the passage of an intravenous contrast bolus through brain was used to construct multislice maps of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and tissue mean transit time (tMTT). We hypothesize that large HW imaging (HWI) abnormalities would be present in treated patients at the time they develop neurological deficit due to vasospasm without matching DW imaging (DWI) abnormalities. RESULTS: Small, sometimes multiple, ischemic lesions on DWI were seen encircled by a large area of decreased rCBF and increased tMTT in all patients with symptomatic vasospasm. Decreases in rCBV were not prominent. MRI hemodynamic abnormalities occurred in regions supplied by vessels with angiographic vasospasm or in their watershed territories. All patients with neurological deficit showed an area of abnormal tMTT much larger than the area of DWI abnormality. MRI images were normal in the asymptomatic patient with angiographic vasospasm and the patient with normal angiogram and no clinical signs of vasospasm. CONCLUSIONS: We conclude that DW/HW MRI in symptomatic vasospasm can detect widespread changes in tissue hemodynamics that encircle early foci of ischemic injury. With additional study, the technique could become a useful tool in the clinical management of patients with SAH.  (+info)

Estrogen provides neuroprotection in transient forebrain ischemia through perfusion-independent mechanisms in rats. (7/2940)

BACKGROUND AND PURPOSE: Estrogen-related neuroprotection in association with animal models of transient forebrain and focal ischemia has been documented in several recent reports. Some of those studies indicated that part of that benefit was a function of improved intraischemic vasodilating capacity. In the present study we examined whether chronic estrogen depletion and repletion affected ischemic neuropathology through perfusion-independent mechanisms. METHODS: Normal, ovariectomized (OVX), and OVX female rats treated with 17beta-estradiol (E2) were subjected to 30 minutes of transient forebrain ischemia (right common carotid occlusion plus hemorrhagic hypotension) and reperfusion. Neurological function and brain histopathology were assessed over the 72-hour recovery period. In all rats, preischemic and intraischemic cortical cerebral blood flow (CBF) levels were monitored with laser-Doppler flowmetry. In additional rats, CBF changes in the striatum and hippocampus were also monitored with laser-Doppler flowmetry probes and radiolabeled microspheres. In each experiment, the level of ischemia was targeted to a 75% to 80% reduction in cortical CBF. RESULTS: The similarity in ischemic severity among groups was supported by measurements of comparable patterns of electroencephalographic power changes during the ischemic period. Compared with normal females, OVX rats showed diminished neurological outcomes and more severe histopathology in the hippocampus and striatum. Two-week treatment of OVX rats with E2 was accompanied by postischemic neuropathological changes similar to those seen in normal females. Intraischemic CBF reductions in the hippocampus and striatum were similar in all groups (to 35% to 50% of the preischemic value) but significantly less than the cortical CBF reductions. CONCLUSIONS: These findings indicate that estrogen provides ischemic neuroprotection through mechanisms unrelated to improvement of intraischemic cerebral perfusion.  (+info)

Nitric oxide production in the CA1 field of the gerbil hippocampus after transient forebrain ischemia : effects of 7-nitroindazole and NG-nitro-L-arginine methyl ester. (8/2940)

BACKGROUND AND PURPOSE: The present study was designed to examine the time course of nitric oxide (NO) production and the source of NO in the CA1 field of the gerbil hippocampus after transient forebrain ischemia. METHODS: The production of NO in the CA1 field of the hippocampus after transient ischemia was monitored consecutively by measuring total NO metabolites (NOx-, NO2- plus NO3-) with the use of brain microdialysis. 7-Nitroindazole (7-NI) and NG-nitro-L-arginine methyl ester were used to dissect the relative contributions of neuronal NO synthase and endothelial NO synthase to the NO production. The histological outcomes of 7-NI in 5- and 10-minute global ischemia were also evaluated. RESULTS: The production of NO in the CA1 field of the hippocampus after ischemia was dependent on the severity of ischemia. Ischemia for 2 or 5 minutes did not induce a significant increase in NOx- levels in the CA1 field of the hippocampus after reperfusion, whereas the 10- and 15-minute ischemias produced significant and persistent increases in NOx- levels. 7-NI did not inhibit the basal NOx- levels and showed no effects on NOx- levels after 5 minutes of ischemia. However, it completely inhibited the increased NOx- levels after 10 or 15 minutes of ischemia. 7-NI provided minor neuroprotection in 5 minutes but not in 10 minutes of global ischemia. CONCLUSIONS: The increased NO level in the CA1 field of the hippocampus after ischemia is produced mostly by neuronal NO synthase, whereas the basal NO level mainly originates from endothelial NO synthase. The observed neuroprotective effect of 7-NI in 5-minute global ischemia in gerbils may not be due to neuronal NO synthase inhibition by this drug.  (+info)

A Transient Ischemic Attack (TIA), also known as a "mini-stroke," is a temporary period of symptoms similar to those you'd get if you were having a stroke. A TIA doesn't cause permanent damage and is often caused by a temporary decrease in blood supply to part of your brain, which may last as little as five minutes.

Like an ischemic stroke, a TIA occurs when a clot or debris blocks blood flow to part of your nervous system. However, unlike a stroke, a TIA doesn't leave lasting damage because the blockage is temporary.

Symptoms of a TIA can include sudden onset of weakness, numbness or paralysis in your face, arm or leg, typically on one side of your body. You could also experience slurred or garbled speech, or difficulty understanding others. Other symptoms can include blindness in one or both eyes, dizziness, or a severe headache with no known cause.

Even though TIAs usually last only a few minutes, they are a serious condition and should not be ignored. If you suspect you or someone else is experiencing a TIA, seek immediate medical attention. TIAs can be a warning sign that a full-blown stroke is imminent.

A stroke, also known as cerebrovascular accident (CVA), is a serious medical condition that occurs when the blood supply to part of the brain is interrupted or reduced, leading to deprivation of oxygen and nutrients to brain cells. This can result in the death of brain tissue and cause permanent damage or temporary impairment to cognitive functions, speech, memory, movement, and other body functions controlled by the affected area of the brain.

Strokes can be caused by either a blockage in an artery that supplies blood to the brain (ischemic stroke) or the rupture of a blood vessel in the brain (hemorrhagic stroke). A transient ischemic attack (TIA), also known as a "mini-stroke," is a temporary disruption of blood flow to the brain that lasts only a few minutes and does not cause permanent damage.

Symptoms of a stroke may include sudden weakness or numbness in the face, arm, or leg; difficulty speaking or understanding speech; vision problems; loss of balance or coordination; severe headache with no known cause; and confusion or disorientation. Immediate medical attention is crucial for stroke patients to receive appropriate treatment and prevent long-term complications.

Cerebrovascular disorders are a group of medical conditions that affect the blood vessels of the brain. These disorders can be caused by narrowing, blockage, or rupture of the blood vessels, leading to decreased blood flow and oxygen supply to the brain. The most common types of cerebrovascular disorders include:

1. Stroke: A stroke occurs when a blood vessel in the brain becomes blocked or bursts, causing a lack of oxygen and nutrients to reach brain cells. This can lead to permanent damage or death of brain tissue.
2. Transient ischemic attack (TIA): Also known as a "mini-stroke," a TIA occurs when blood flow to the brain is temporarily blocked, often by a blood clot. Symptoms may last only a few minutes to a few hours and typically resolve on their own. However, a TIA is a serious warning sign that a full-blown stroke may occur in the future.
3. Aneurysm: An aneurysm is a weakened or bulging area in the wall of a blood vessel. If left untreated, an aneurysm can rupture and cause bleeding in the brain.
4. Arteriovenous malformation (AVM): An AVM is a tangled mass of abnormal blood vessels that connect arteries and veins. This can lead to bleeding in the brain or stroke.
5. Carotid stenosis: Carotid stenosis occurs when the carotid arteries, which supply blood to the brain, become narrowed or blocked due to plaque buildup. This can increase the risk of stroke.
6. Vertebrobasilar insufficiency: This condition occurs when the vertebral and basilar arteries, which supply blood to the back of the brain, become narrowed or blocked. This can lead to symptoms such as dizziness, vertigo, and difficulty swallowing.

Cerebrovascular disorders are a leading cause of disability and death worldwide. Risk factors for these conditions include age, high blood pressure, smoking, diabetes, high cholesterol, and family history. Treatment may involve medications, surgery, or lifestyle changes to reduce the risk of further complications.

Brain ischemia is the medical term used to describe a reduction or interruption of blood flow to the brain, leading to a lack of oxygen and glucose delivery to brain tissue. This can result in brain damage or death of brain cells, known as infarction. Brain ischemia can be caused by various conditions such as thrombosis (blood clot formation), embolism (obstruction of a blood vessel by a foreign material), or hypoperfusion (reduced blood flow). The severity and duration of the ischemia determine the extent of brain damage. Symptoms can range from mild, such as transient ischemic attacks (TIAs or "mini-strokes"), to severe, including paralysis, speech difficulties, loss of consciousness, and even death. Immediate medical attention is required for proper diagnosis and treatment to prevent further damage and potential long-term complications.

Carotid stenosis is a medical condition that refers to the narrowing or constriction of the lumen (inner space) of the carotid artery. The carotid arteries are major blood vessels that supply oxygenated blood to the head and neck. Carotid stenosis usually results from the buildup of plaque, made up of fat, cholesterol, calcium, and other substances, on the inner walls of the artery. This process is called atherosclerosis.

As the plaque accumulates, it causes the artery to narrow, reducing blood flow to the brain. Severe carotid stenosis can increase the risk of stroke, as a clot or debris from the plaque can break off and travel to the brain, blocking a smaller blood vessel and causing tissue damage or death.

Carotid stenosis is typically diagnosed through imaging tests such as ultrasound, CT angiography, or MRI angiography. Treatment options may include lifestyle modifications (such as quitting smoking, controlling blood pressure, and managing cholesterol levels), medications to reduce the risk of clots, or surgical procedures like endarterectomy or stenting to remove or bypass the blockage.

Carotid artery diseases refer to conditions that affect the carotid arteries, which are the major blood vessels that supply oxygen-rich blood to the head and neck. The most common type of carotid artery disease is atherosclerosis, which occurs when fatty deposits called plaques build up in the inner lining of the arteries.

These plaques can cause the arteries to narrow or become blocked, reducing blood flow to the brain and increasing the risk of stroke. Other carotid artery diseases include carotid artery dissection, which occurs when there is a tear in the inner lining of the artery, and fibromuscular dysplasia, which is a condition that affects the muscle and tissue in the walls of the artery.

Symptoms of carotid artery disease may include neck pain or pulsations, transient ischemic attacks (TIAs) or "mini-strokes," and strokes. Treatment options for carotid artery disease depend on the severity and type of the condition but may include lifestyle changes, medications, endarterectomy (a surgical procedure to remove plaque from the artery), or angioplasty and stenting (procedures to open blocked arteries using a balloon and stent).

Carotid endarterectomy is a surgical procedure to remove plaque buildup (atherosclerosis) from the carotid arteries, which are the major blood vessels that supply oxygen-rich blood to the brain. The surgery involves making an incision in the neck, opening the carotid artery, and removing the plaque from the inside of the artery wall. The goal of the procedure is to restore normal blood flow to the brain and reduce the risk of stroke caused by the narrowing or blockage of the carotid arteries.

Medical Definition:

"Risk factors" are any attribute, characteristic or exposure of an individual that increases the likelihood of developing a disease or injury. They can be divided into modifiable and non-modifiable risk factors. Modifiable risk factors are those that can be changed through lifestyle choices or medical treatment, while non-modifiable risk factors are inherent traits such as age, gender, or genetic predisposition. Examples of modifiable risk factors include smoking, alcohol consumption, physical inactivity, and unhealthy diet, while non-modifiable risk factors include age, sex, and family history. It is important to note that having a risk factor does not guarantee that a person will develop the disease, but rather indicates an increased susceptibility.

Cerebral infarction, also known as a "stroke" or "brain attack," is the sudden death of brain cells caused by the interruption of their blood supply. It is most commonly caused by a blockage in one of the blood vessels supplying the brain (an ischemic stroke), but can also result from a hemorrhage in or around the brain (a hemorrhagic stroke).

Ischemic strokes occur when a blood clot or other particle blocks a cerebral artery, cutting off blood flow to a part of the brain. The lack of oxygen and nutrients causes nearby brain cells to die. Hemorrhagic strokes occur when a weakened blood vessel ruptures, causing bleeding within or around the brain. This bleeding can put pressure on surrounding brain tissues, leading to cell death.

Symptoms of cerebral infarction depend on the location and extent of the affected brain tissue but may include sudden weakness or numbness in the face, arm, or leg; difficulty speaking or understanding speech; vision problems; loss of balance or coordination; and severe headache with no known cause. Immediate medical attention is crucial for proper diagnosis and treatment to minimize potential long-term damage or disability.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Recurrence, in a medical context, refers to the return of symptoms or signs of a disease after a period of improvement or remission. It indicates that the condition has not been fully eradicated and may require further treatment. Recurrence is often used to describe situations where a disease such as cancer comes back after initial treatment, but it can also apply to other medical conditions. The likelihood of recurrence varies depending on the type of disease and individual patient factors.

Endarterectomy is a surgical procedure in which the inner lining of an artery (the endothelium) that has become thickened, damaged, or narrowed due to the buildup of fatty deposits, called plaques, is removed. This process helps restore normal blood flow through the artery and reduces the risk of serious complications such as stroke or limb loss.

The procedure typically involves making an incision in the affected artery, carefully removing the plaque and inner lining, and then closing the artery with sutures or a patch graft. Endarterectomy is most commonly performed on the carotid arteries in the neck, but it can also be done on other arteries throughout the body, including the femoral artery in the leg and the iliac artery in the pelvis.

Endarterectomy is usually recommended for patients with significant narrowing of their arteries who are experiencing symptoms such as pain, numbness, or weakness in their limbs, or who have a high risk of stroke due to carotid artery disease. The procedure is generally safe and effective, but like any surgery, it carries risks such as bleeding, infection, and damage to nearby nerves or tissues.

Follow-up studies are a type of longitudinal research that involve repeated observations or measurements of the same variables over a period of time, in order to understand their long-term effects or outcomes. In medical context, follow-up studies are often used to evaluate the safety and efficacy of medical treatments, interventions, or procedures.

In a typical follow-up study, a group of individuals (called a cohort) who have received a particular treatment or intervention are identified and then followed over time through periodic assessments or data collection. The data collected may include information on clinical outcomes, adverse events, changes in symptoms or functional status, and other relevant measures.

The results of follow-up studies can provide important insights into the long-term benefits and risks of medical interventions, as well as help to identify factors that may influence treatment effectiveness or patient outcomes. However, it is important to note that follow-up studies can be subject to various biases and limitations, such as loss to follow-up, recall bias, and changes in clinical practice over time, which must be carefully considered when interpreting the results.

Intracranial arteriosclerosis is a medical condition characterized by the thickening and hardening of the walls of the intracranial arteries, which are the blood vessels that supply blood to the brain. This process is caused by the buildup of plaque, made up of fat, cholesterol, and other substances, within the walls of the arteries.

Intracranial arteriosclerosis can lead to a narrowing or blockage of the affected arteries, reducing blood flow to the brain. This can result in various neurological symptoms, such as headaches, dizziness, seizures, and transient ischemic attacks (TIAs) or strokes.

The condition is more common in older adults, particularly those with a history of hypertension, diabetes, smoking, and high cholesterol levels. Intracranial arteriosclerosis can be diagnosed through imaging tests such as magnetic resonance angiography (MRA) or computed tomographic angiography (CTA). Treatment typically involves managing risk factors and may include medications to control blood pressure, cholesterol levels, and prevent blood clots. In severe cases, surgical procedures such as angioplasty and stenting may be necessary to open up the affected arteries.

Cerebral angiography is a medical procedure that involves taking X-ray images of the blood vessels in the brain after injecting a contrast dye into them. This procedure helps doctors to diagnose and treat various conditions affecting the blood vessels in the brain, such as aneurysms, arteriovenous malformations, and stenosis (narrowing of the blood vessels).

During the procedure, a catheter is inserted into an artery in the leg and threaded through the body to the blood vessels in the neck or brain. The contrast dye is then injected through the catheter, and X-ray images are taken to visualize the blood flow through the brain's blood vessels.

Cerebral angiography provides detailed images of the blood vessels in the brain, allowing doctors to identify any abnormalities or blockages that may be causing symptoms or increasing the risk of stroke. Based on the results of the cerebral angiography, doctors can develop a treatment plan to address these issues and prevent further complications.

Prospective studies, also known as longitudinal studies, are a type of cohort study in which data is collected forward in time, following a group of individuals who share a common characteristic or exposure over a period of time. The researchers clearly define the study population and exposure of interest at the beginning of the study and follow up with the participants to determine the outcomes that develop over time. This type of study design allows for the investigation of causal relationships between exposures and outcomes, as well as the identification of risk factors and the estimation of disease incidence rates. Prospective studies are particularly useful in epidemiology and medical research when studying diseases with long latency periods or rare outcomes.

An intracranial embolism is a medical condition that occurs when a blood clot or other foreign material (embolus) forms elsewhere in the body and travels to the blood vessels within the brain. This embolus then blocks the flow of blood in the cerebral arteries, leading to potential damage or death of brain tissue. Common sources of intracranial emboli include heart conditions such as atrial fibrillation, valvular heart disease, or following a heart attack; or from large-vessel atherosclerosis in the carotid arteries. Symptoms can vary depending on the location and size of the obstruction, but may include sudden weakness or numbness, confusion, difficulty speaking, vision loss, severe headache, or even loss of consciousness. Immediate medical attention is required to diagnose and treat intracranial embolism, often involving anticoagulation therapy, endovascular procedures, or surgery.

The internal carotid artery is a major blood vessel that supplies oxygenated blood to the brain. It originates from the common carotid artery and passes through the neck, entering the skull via the carotid canal in the temporal bone. Once inside the skull, it branches into several smaller vessels that supply different parts of the brain with blood.

The internal carotid artery is divided into several segments: cervical, petrous, cavernous, clinoid, and supraclinoid. Each segment has distinct clinical significance in terms of potential injury or disease. The most common conditions affecting the internal carotid artery include atherosclerosis, which can lead to stroke or transient ischemic attack (TIA), and dissection, which can cause severe headache, neck pain, and neurological symptoms.

It's important to note that any blockage or damage to the internal carotid artery can have serious consequences, as it can significantly reduce blood flow to the brain and lead to permanent neurological damage or even death. Therefore, regular check-ups and screening tests are recommended for individuals at high risk of developing vascular diseases.

Intracranial arterial diseases refer to conditions that affect the blood vessels within the brain. These diseases can include stenosis (narrowing) or occlusion (blockage) of the intracranial arteries, aneurysms (bulging or weakened areas in the artery wall), and vasculitis (inflammation of the blood vessel walls).

These conditions can lead to serious complications such as stroke, transient ischemic attack (TIA or "mini-stroke"), bleeding in the brain, and cognitive decline. Risk factors for intracranial arterial diseases include age, hypertension, diabetes, smoking, high cholesterol, and a history of heart disease.

Diagnosis of intracranial arterial diseases may involve imaging tests such as magnetic resonance angiography (MRA), computed tomographic angiography (CTA), or digital subtraction angiography (DSA). Treatment options may include medications to manage risk factors, endovascular procedures such as angioplasty and stenting, or surgical intervention in some cases.

Neurology is a branch of medicine that deals with the study and treatment of diseases and disorders of the nervous system, which includes the brain, spinal cord, peripheral nerves, muscles, and autonomic nervous system. Neurologists are medical doctors who specialize in this field, diagnosing and treating conditions such as stroke, Alzheimer's disease, epilepsy, Parkinson's disease, multiple sclerosis, and various types of headaches and pain disorders. They use a variety of diagnostic tests, including imaging studies like MRI and CT scans, electrophysiological tests like EEG and EMG, and laboratory tests to evaluate nerve function and identify any underlying conditions or abnormalities. Treatment options may include medication, surgery, rehabilitation, or lifestyle modifications.

1. Intracranial Embolism: This is a medical condition that occurs when a blood clot or other particle (embolus) formed elsewhere in the body, travels through the bloodstream and lodges itself in the intracranial blood vessels, blocking the flow of blood to a part of the brain. This can lead to various neurological symptoms such as weakness, numbness, speech difficulties, or even loss of consciousness, depending on the severity and location of the blockage.

2. Intracranial Thrombosis: This is a medical condition that occurs when a blood clot (thrombus) forms within the intracranial blood vessels. The clot can partially or completely obstruct the flow of blood, leading to various symptoms such as headache, confusion, seizures, or neurological deficits, depending on the severity and location of the thrombosis. Intracranial thrombosis can occur due to various factors including atherosclerosis, hypertension, diabetes, and other medical conditions that increase the risk of blood clot formation.

Moyamoya Disease is a rare, progressive cerebrovascular disorder characterized by the narrowing or occlusion (blockage) of the internal carotid artery and its main branches. The name "moyamoya" means "puff of smoke" in Japanese and describes the look of the tangle of tiny vessels formed to compensate for the blockage. Over time, these fragile vessels can become less effective or rupture, leading to transient ischemic attacks (mini-strokes), strokes, bleeding in the brain, or cognitive decline. The exact cause of moyamoya disease is unknown, but it may be associated with genetic factors and certain medical conditions such as Down syndrome, neurofibromatosis type 1, and sickle cell anemia. Treatment options include surgical procedures to improve blood flow to the brain.

Aspirin is the common name for acetylsalicylic acid, which is a medication used to relieve pain, reduce inflammation, and lower fever. It works by inhibiting the activity of an enzyme called cyclooxygenase (COX), which is involved in the production of prostaglandins, hormone-like substances that cause inflammation and pain. Aspirin also has an antiplatelet effect, which means it can help prevent blood clots from forming. This makes it useful for preventing heart attacks and strokes.

Aspirin is available over-the-counter in various forms, including tablets, capsules, and chewable tablets. It is also available in prescription strengths for certain medical conditions. As with any medication, aspirin should be taken as directed by a healthcare provider, and its use should be avoided in children and teenagers with viral infections due to the risk of Reye's syndrome, a rare but serious condition that can affect the liver and brain.

The carotid arteries are a pair of vital blood vessels in the human body that supply oxygenated blood to the head and neck. Each person has two common carotid arteries, one on each side of the neck, which branch off from the aorta, the largest artery in the body.

The right common carotid artery originates from the brachiocephalic trunk, while the left common carotid artery arises directly from the aortic arch. As they ascend through the neck, they split into two main branches: the internal and external carotid arteries.

The internal carotid artery supplies oxygenated blood to the brain, eyes, and other structures within the skull, while the external carotid artery provides blood to the face, scalp, and various regions of the neck.

Maintaining healthy carotid arteries is crucial for overall cardiovascular health and preventing serious conditions like stroke, which can occur when the arteries become narrowed or blocked due to the buildup of plaque or fatty deposits (atherosclerosis). Regular check-ups with healthcare professionals may include monitoring carotid artery health through ultrasound or other imaging techniques.

Amaurosis fugax is a medical term that describes a temporary loss of vision in one eye, which is often described as a "shade or curtain falling over the field of vision." It's usually caused by a temporary interruption of blood flow to the retina or optic nerve. This condition is often associated with conditions such as giant cell arteritis, carotid artery stenosis, and cardiovascular disease.

It's important to note that Amaurosis fugax can be a warning sign for a more serious medical event, such as a stroke, so it's essential to seek medical attention promptly if you experience any symptoms of this condition.

An embolism is a medical condition that occurs when a substance, such as a blood clot or an air bubble, blocks a blood vessel. This can happen in any part of the body, but it is particularly dangerous when it affects the brain (causing a stroke) or the lungs (causing a pulmonary embolism). Embolisms can cause serious harm by preventing oxygen and nutrients from reaching the tissues and organs that need them. They are often the result of underlying medical conditions, such as heart disease or deep vein thrombosis, and may require immediate medical attention to prevent further complications.

Vertebrobasilar insufficiency (VBI) is a medical condition characterized by inadequate blood flow to the vertebral and basilar arteries, which supply oxygenated blood to the brainstem and cerebellum. These arteries arise from the subclavian arteries and merge to form the basilar artery, which supplies critical structures in the posterior circulation of the brain.

VBI is often caused by atherosclerosis, or the buildup of plaque in the arterial walls, leading to narrowing (stenosis) or occlusion of these vessels. Other causes include embolism, arterial dissection, and vasculitis. The decreased blood flow can result in various neurological symptoms, such as dizziness, vertigo, imbalance, difficulty swallowing, slurred speech, visual disturbances, and even transient ischemic attacks (TIAs) or strokes.

Diagnosis of VBI typically involves a combination of clinical evaluation, imaging studies like MRA or CTA, and sometimes cerebral angiography to assess the extent and location of vascular narrowing or occlusion. Treatment options may include lifestyle modifications, medications to manage risk factors (such as hypertension, diabetes, or high cholesterol), antiplatelet therapy, or surgical interventions like endarterectomy or stenting in severe cases.

Secondary prevention in a medical context refers to actions taken to detect and treat a disease or condition early in its course, before it causes significant symptoms or complications. This is often done through screening, monitoring, and early intervention in high-risk individuals who have previously been identified as having a higher likelihood of developing the disease based on their personal or family medical history, lifestyle factors, or other risk factors.

The goal of secondary prevention is to reduce the burden of disease, improve outcomes, and prevent or delay complications. Examples of secondary prevention measures include regular mammograms and breast exams for women with a family history of breast cancer, cholesterol screening for people with a history of heart disease, and colonoscopies for individuals at high risk for colorectal cancer.

Secondary prevention is an important component of overall preventive healthcare, as it can help to reduce the incidence and severity of diseases, improve quality of life, and reduce healthcare costs.

Anticoagulants are a class of medications that work to prevent the formation of blood clots in the body. They do this by inhibiting the coagulation cascade, which is a series of chemical reactions that lead to the formation of a clot. Anticoagulants can be given orally, intravenously, or subcutaneously, depending on the specific drug and the individual patient's needs.

There are several different types of anticoagulants, including:

1. Heparin: This is a naturally occurring anticoagulant that is often used in hospitalized patients who require immediate anticoagulation. It works by activating an enzyme called antithrombin III, which inhibits the formation of clots.
2. Low molecular weight heparin (LMWH): LMWH is a form of heparin that has been broken down into smaller molecules. It has a longer half-life than standard heparin and can be given once or twice daily by subcutaneous injection.
3. Direct oral anticoagulants (DOACs): These are newer oral anticoagulants that work by directly inhibiting specific clotting factors in the coagulation cascade. Examples include apixaban, rivaroxaban, and dabigatran.
4. Vitamin K antagonists: These are older oral anticoagulants that work by inhibiting the action of vitamin K, which is necessary for the formation of clotting factors. Warfarin is an example of a vitamin K antagonist.

Anticoagulants are used to prevent and treat a variety of conditions, including deep vein thrombosis (DVT), pulmonary embolism (PE), atrial fibrillation, and prosthetic heart valve thrombosis. It is important to note that anticoagulants can increase the risk of bleeding, so they must be used with caution and regular monitoring of blood clotting times may be required.

Platelet aggregation inhibitors are a class of medications that prevent platelets (small blood cells involved in clotting) from sticking together and forming a clot. These drugs work by interfering with the ability of platelets to adhere to each other and to the damaged vessel wall, thereby reducing the risk of thrombosis (blood clot formation).

Platelet aggregation inhibitors are often prescribed for people who have an increased risk of developing blood clots due to various medical conditions such as atrial fibrillation, coronary artery disease, peripheral artery disease, stroke, or a history of heart attack. They may also be used in patients undergoing certain medical procedures, such as angioplasty and stenting, to prevent blood clot formation in the stents.

Examples of platelet aggregation inhibitors include:

1. Aspirin: A nonsteroidal anti-inflammatory drug (NSAID) that irreversibly inhibits the enzyme cyclooxygenase, which is involved in platelet activation and aggregation.
2. Clopidogrel (Plavix): A P2Y12 receptor antagonist that selectively blocks ADP-induced platelet activation and aggregation.
3. Prasugrel (Effient): A third-generation thienopyridine P2Y12 receptor antagonist, similar to clopidogrel but with faster onset and greater potency.
4. Ticagrelor (Brilinta): A direct-acting P2Y12 receptor antagonist that does not require metabolic activation and has a reversible binding profile.
5. Dipyridamole (Persantine): An antiplatelet agent that inhibits platelet aggregation by increasing cyclic adenosine monophosphate (cAMP) levels in platelets, which leads to decreased platelet reactivity.
6. Iloprost (Ventavis): A prostacyclin analogue that inhibits platelet aggregation and causes vasodilation, often used in the treatment of pulmonary arterial hypertension.
7. Cilostazol (Pletal): A phosphodiesterase III inhibitor that increases cAMP levels in platelets, leading to decreased platelet activation and aggregation, as well as vasodilation.
8. Ticlopidine (Ticlid): An older P2Y12 receptor antagonist with a slower onset of action and more frequent side effects compared to clopidogrel or prasugrel.

Treatment outcome is a term used to describe the result or effect of medical treatment on a patient's health status. It can be measured in various ways, such as through symptoms improvement, disease remission, reduced disability, improved quality of life, or survival rates. The treatment outcome helps healthcare providers evaluate the effectiveness of a particular treatment plan and make informed decisions about future care. It is also used in clinical research to compare the efficacy of different treatments and improve patient care.

X-ray computed tomography (CT or CAT scan) is a medical imaging method that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional (tomographic) images (virtual "slices") of the body. These cross-sectional images can then be used to display detailed internal views of organs, bones, and soft tissues in the body.

The term "computed tomography" is used instead of "CT scan" or "CAT scan" because the machines take a series of X-ray measurements from different angles around the body and then use a computer to process these data to create detailed images of internal structures within the body.

CT scanning is a noninvasive, painless medical test that helps physicians diagnose and treat medical conditions. CT imaging provides detailed information about many types of tissue including lung, bone, soft tissue and blood vessels. CT examinations can be performed on every part of the body for a variety of reasons including diagnosis, surgical planning, and monitoring of therapeutic responses.

In computed tomography (CT), an X-ray source and detector rotate around the patient, measuring the X-ray attenuation at many different angles. A computer uses this data to construct a cross-sectional image by the process of reconstruction. This technique is called "tomography". The term "computed" refers to the use of a computer to reconstruct the images.

CT has become an important tool in medical imaging and diagnosis, allowing radiologists and other physicians to view detailed internal images of the body. It can help identify many different medical conditions including cancer, heart disease, lung nodules, liver tumors, and internal injuries from trauma. CT is also commonly used for guiding biopsies and other minimally invasive procedures.

In summary, X-ray computed tomography (CT or CAT scan) is a medical imaging technique that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional images of the body. It provides detailed internal views of organs, bones, and soft tissues in the body, allowing physicians to diagnose and treat medical conditions.

Atrial fibrillation (A-tre-al fi-bru-la'shun) is a type of abnormal heart rhythm characterized by rapid and irregular beating of the atria, the upper chambers of the heart. In this condition, the electrical signals that coordinate heartbeats don't function properly, causing the atria to quiver instead of contracting effectively. As a result, blood may not be pumped efficiently into the ventricles, which can lead to blood clots, stroke, and other complications. Atrial fibrillation is a common type of arrhythmia and can cause symptoms such as palpitations, shortness of breath, fatigue, and dizziness. It can be caused by various factors, including heart disease, high blood pressure, age, and genetics. Treatment options include medications, electrical cardioversion, and surgical procedures to restore normal heart rhythm.

A cerebral hemorrhage, also known as an intracranial hemorrhage or intracerebral hemorrhage, is a type of stroke that results from bleeding within the brain tissue. It occurs when a weakened blood vessel bursts and causes localized bleeding in the brain. This bleeding can increase pressure in the skull, damage nearby brain cells, and release toxic substances that further harm brain tissues.

Cerebral hemorrhages are often caused by chronic conditions like hypertension (high blood pressure) or cerebral amyloid angiopathy, which weakens the walls of blood vessels over time. Other potential causes include trauma, aneurysms, arteriovenous malformations, illicit drug use, and brain tumors. Symptoms may include sudden headache, weakness, numbness, difficulty speaking or understanding speech, vision problems, loss of balance, and altered level of consciousness. Immediate medical attention is required to diagnose and manage cerebral hemorrhage through imaging techniques, supportive care, and possible surgical interventions.

Posterior cerebral artery (PCA) infarction refers to the death of brain tissue in the region of the brain supplied by the posterior cerebral artery due to insufficient blood supply. The PCA supplies blood to the occipital lobe (responsible for vision), parts of the temporal lobe, and other structures in the brain.

PCA infarction can result from various conditions that cause a blockage or reduction of blood flow in the PCA, such as embolism (a clot or debris traveling from another part of the body), thrombosis (a blood clot forming within the artery), or dissection (tearing of the artery wall). Symptoms of PCA infarction may include visual loss or disturbances, memory problems, language impairment, and other neurological deficits, depending on the extent and location of the infarction.

A migraine disorder is a neurological condition characterized by recurrent headaches that often involve one side of the head and are accompanied by various symptoms such as nausea, vomiting, sensitivity to light and sound, and visual disturbances. Migraines can last from several hours to days and can be severely debilitating. The exact cause of migraines is not fully understood, but they are believed to result from a combination of genetic and environmental factors that affect the brain and blood vessels. There are different types of migraines, including migraine without aura, migraine with aura, chronic migraine, and others, each with its own specific set of symptoms and diagnostic criteria. Treatment typically involves a combination of lifestyle changes, medications, and behavioral therapies to manage symptoms and prevent future attacks.

Cerebral arteries refer to the blood vessels that supply oxygenated blood to the brain. These arteries branch off from the internal carotid arteries and the vertebral arteries, which combine to form the basilar artery. The major cerebral arteries include:

1. Anterior cerebral artery (ACA): This artery supplies blood to the frontal lobes of the brain, including the motor and sensory cortices responsible for movement and sensation in the lower limbs.
2. Middle cerebral artery (MCA): The MCA is the largest of the cerebral arteries and supplies blood to the lateral surface of the brain, including the temporal, parietal, and frontal lobes. It is responsible for providing blood to areas involved in motor function, sensory perception, speech, memory, and vision.
3. Posterior cerebral artery (PCA): The PCA supplies blood to the occipital lobe, which is responsible for visual processing, as well as parts of the temporal and parietal lobes.
4. Anterior communicating artery (ACoA) and posterior communicating arteries (PComAs): These are small arteries that connect the major cerebral arteries, forming an important circulatory network called the Circle of Willis. The ACoA connects the two ACAs, while the PComAs connect the ICA with the PCA and the basilar artery.

These cerebral arteries play a crucial role in maintaining proper brain function by delivering oxygenated blood to various regions of the brain. Any damage or obstruction to these arteries can lead to serious neurological conditions, such as strokes or transient ischemic attacks (TIAs).

A cohort study is a type of observational study in which a group of individuals who share a common characteristic or exposure are followed up over time to determine the incidence of a specific outcome or outcomes. The cohort, or group, is defined based on the exposure status (e.g., exposed vs. unexposed) and then monitored prospectively to assess for the development of new health events or conditions.

Cohort studies can be either prospective or retrospective in design. In a prospective cohort study, participants are enrolled and followed forward in time from the beginning of the study. In contrast, in a retrospective cohort study, researchers identify a cohort that has already been assembled through medical records, insurance claims, or other sources and then look back in time to assess exposure status and health outcomes.

Cohort studies are useful for establishing causality between an exposure and an outcome because they allow researchers to observe the temporal relationship between the two. They can also provide information on the incidence of a disease or condition in different populations, which can be used to inform public health policy and interventions. However, cohort studies can be expensive and time-consuming to conduct, and they may be subject to bias if participants are not representative of the population or if there is loss to follow-up.

Magnetic Resonance Angiography (MRA) is a non-invasive medical imaging technique that uses magnetic fields and radio waves to create detailed images of the blood vessels or arteries within the body. It is a type of Magnetic Resonance Imaging (MRI) that focuses specifically on the circulatory system.

MRA can be used to diagnose and evaluate various conditions related to the blood vessels, such as aneurysms, stenosis (narrowing of the vessel), or the presence of plaques or tumors. It can also be used to plan for surgeries or other treatments related to the vascular system. The procedure does not use radiation and is generally considered safe, although people with certain implants like pacemakers may not be able to have an MRA due to safety concerns.

The Predictive Value of Tests, specifically the Positive Predictive Value (PPV) and Negative Predictive Value (NPV), are measures used in diagnostic tests to determine the probability that a positive or negative test result is correct.

Positive Predictive Value (PPV) is the proportion of patients with a positive test result who actually have the disease. It is calculated as the number of true positives divided by the total number of positive results (true positives + false positives). A higher PPV indicates that a positive test result is more likely to be a true positive, and therefore the disease is more likely to be present.

Negative Predictive Value (NPV) is the proportion of patients with a negative test result who do not have the disease. It is calculated as the number of true negatives divided by the total number of negative results (true negatives + false negatives). A higher NPV indicates that a negative test result is more likely to be a true negative, and therefore the disease is less likely to be present.

The predictive value of tests depends on the prevalence of the disease in the population being tested, as well as the sensitivity and specificity of the test. A test with high sensitivity and specificity will generally have higher predictive values than a test with low sensitivity and specificity. However, even a highly sensitive and specific test can have low predictive values if the prevalence of the disease is low in the population being tested.

Cerebrovascular circulation refers to the network of blood vessels that supply oxygenated blood and nutrients to the brain tissue, and remove waste products. It includes the internal carotid arteries, vertebral arteries, circle of Willis, and the intracranial arteries that branch off from them.

The internal carotid arteries and vertebral arteries merge to form the circle of Willis, a polygonal network of vessels located at the base of the brain. The anterior cerebral artery, middle cerebral artery, posterior cerebral artery, and communicating arteries are the major vessels that branch off from the circle of Willis and supply blood to different regions of the brain.

Interruptions or abnormalities in the cerebrovascular circulation can lead to various neurological conditions such as stroke, transient ischemic attack (TIA), and vascular dementia.

Patent Foramen Ovale (PFO) is a medical condition where the foramen ovale, an opening between the left and right atria of the heart in a fetus, does not close completely after birth. This results in a small flap-like opening that allows blood to pass from the right atrium to the left atrium. While this condition is typically harmless in itself, it can potentially allow blood clots to pass from the right side of the heart to the left, which could then travel to the brain and cause a stroke. Patent Foramen Ovale is usually an incidental finding during tests for other conditions.

In the context of medicine, risk is the probability or likelihood of an adverse health effect or the occurrence of a negative event related to treatment or exposure to certain hazards. It is usually expressed as a ratio or percentage and can be influenced by various factors such as age, gender, lifestyle, genetics, and environmental conditions. Risk assessment involves identifying, quantifying, and prioritizing risks to make informed decisions about prevention, mitigation, or treatment strategies.

Sulfinpyrazone is a medication that belongs to the class of drugs known as uricosurics. It works by increasing the amount of uric acid that is removed from the body through urine, which helps to lower the levels of uric acid in the blood. This makes it useful for the treatment of conditions such as gout and kidney stones that are caused by high levels of uric acid.

In addition to its uricosuric effects, sulfinpyrazone also has antiplatelet properties, which means that it can help to prevent blood clots from forming. This makes it useful for the prevention of heart attacks and strokes in people who are at risk.

Sulfinpyrazone is available by prescription and is typically taken by mouth in the form of tablets. It may be used alone or in combination with other medications, depending on the individual patient's needs and medical condition. As with any medication, sulfinpyrazone should be used under the supervision of a healthcare provider, and patients should follow their provider's instructions carefully to ensure safe and effective use.

Emergency Medical Services (EMS) is a system that provides immediate and urgent medical care, transportation, and treatment to patients who are experiencing an acute illness or injury that poses an immediate threat to their health, safety, or life. EMS is typically composed of trained professionals, such as emergency medical technicians (EMTs), paramedics, and first responders, who work together to assess a patient's condition, administer appropriate medical interventions, and transport the patient to a hospital or other medical facility for further treatment.

The goal of EMS is to quickly and effectively stabilize patients in emergency situations, prevent further injury or illness, and ensure that they receive timely and appropriate medical care. This may involve providing basic life support (BLS) measures such as cardiopulmonary resuscitation (CPR), controlling bleeding, and managing airway obstructions, as well as more advanced interventions such as administering medications, establishing intravenous lines, and performing emergency procedures like intubation or defibrillation.

EMS systems are typically organized and managed at the local or regional level, with coordination and oversight provided by public health agencies, hospitals, and other healthcare organizations. EMS providers may work for private companies, non-profit organizations, or government agencies, and they may be dispatched to emergencies via 911 or other emergency response systems.

In summary, Emergency Medical Services (EMS) is a critical component of the healthcare system that provides urgent medical care and transportation to patients who are experiencing acute illnesses or injuries. EMS professionals work together to quickly assess, stabilize, and transport patients to appropriate medical facilities for further treatment.

Diffusion Magnetic Resonance Imaging (MRI) is a non-invasive medical imaging technique that uses magnetic fields and radio waves to produce detailed images of the body's internal structures, particularly the brain and nervous system. In diffusion MRI, the movement of water molecules in biological tissues is measured and analyzed to generate contrast in the images based on the microstructural properties of the tissue.

Diffusion MRI is unique because it allows for the measurement of water diffusion in various directions, which can reveal important information about the organization and integrity of nerve fibers in the brain. This technique has been widely used in research and clinical settings to study a variety of neurological conditions, including stroke, traumatic brain injury, multiple sclerosis, and neurodegenerative diseases such as Alzheimer's disease.

In summary, diffusion MRI is a specialized type of MRI that measures the movement of water molecules in biological tissues to generate detailed images of the body's internal structures, particularly the brain and nervous system. It provides valuable information about the microstructural properties of tissues and has important applications in both research and clinical settings.

Retrospective studies, also known as retrospective research or looking back studies, are a type of observational study that examines data from the past to draw conclusions about possible causal relationships between risk factors and outcomes. In these studies, researchers analyze existing records, medical charts, or previously collected data to test a hypothesis or answer a specific research question.

Retrospective studies can be useful for generating hypotheses and identifying trends, but they have limitations compared to prospective studies, which follow participants forward in time from exposure to outcome. Retrospective studies are subject to biases such as recall bias, selection bias, and information bias, which can affect the validity of the results. Therefore, retrospective studies should be interpreted with caution and used primarily to generate hypotheses for further testing in prospective studies.

Warfarin is a anticoagulant medication that works by inhibiting the vitamin K-dependent activation of several coagulation factors (factors II, VII, IX, and X). This results in prolonged clotting times and reduced thrombus formation. It is commonly used to prevent and treat blood clots in conditions such as atrial fibrillation, deep vein thrombosis, and pulmonary embolism. Warfarin is also known by its brand names Coumadin and Jantoven.

It's important to note that warfarin has a narrow therapeutic index, meaning that the difference between an effective dose and a toxic one is small. Therefore, it requires careful monitoring of the patient's coagulation status through regular blood tests (INR) to ensure that the dosage is appropriate and to minimize the risk of bleeding complications.

Risk assessment in the medical context refers to the process of identifying, evaluating, and prioritizing risks to patients, healthcare workers, or the community related to healthcare delivery. It involves determining the likelihood and potential impact of adverse events or hazards, such as infectious diseases, medication errors, or medical devices failures, and implementing measures to mitigate or manage those risks. The goal of risk assessment is to promote safe and high-quality care by identifying areas for improvement and taking action to minimize harm.

The Babinski reflex, also known as the plantar reflex, is a physiological response that originates from the spinal cord when the sole of the foot is stimulated. It is named after Joseph François Felix Babinski, a French neurologist who described it in 1896.

In a normal, healthy adult, this stimulation typically results in the downward flexion of the big toe and the fanning out of the other toes. However, in infants and young children, as well as in some individuals with certain neurological conditions, the opposite response may occur - the big toe extends upward (dorsiflexes) while the other toes fan out. This is known as the Babinski reflex and can be a sign of damage to the brain or spinal cord, particularly to the nerve pathways that run from the cortex to the spinal cord.

It's important to note that the presence of an extensor plantar response (Babinski reflex) in adults is considered abnormal and may indicate a neurological disorder such as a brain injury, spinal cord injury, multiple sclerosis, or motor neuron disease. However, it's worth mentioning that certain medications, intoxication, or temporary conditions like sleep deprivation can also cause an abnormal plantar response, so further evaluation is necessary to confirm any diagnosis.

Auscultation is a medical procedure in which a healthcare professional uses a stethoscope to listen to the internal sounds of the body, such as heart, lung, or abdominal sounds. These sounds can provide important clues about a person's health and help diagnose various medical conditions, such as heart valve problems, lung infections, or digestive issues.

During auscultation, the healthcare professional places the stethoscope on different parts of the body and listens for any abnormal sounds, such as murmurs, rubs, or wheezes. They may also ask the person to perform certain movements, such as breathing deeply or coughing, to help identify any changes in the sounds.

Auscultation is a simple, non-invasive procedure that can provide valuable information about a person's health. It is an essential part of a physical examination and is routinely performed by healthcare professionals during regular checkups and hospital visits.

Transcranial Doppler ultrasonography is a non-invasive diagnostic technique that uses high-frequency sound waves to visualize and measure the velocity of blood flow in the cerebral arteries located in the skull. This imaging modality employs the Doppler effect, which describes the change in frequency of sound waves as they reflect off moving red blood cells. By measuring the frequency shift of the reflected ultrasound waves, the velocity and direction of blood flow can be determined.

Transcranial Doppler ultrasonography is primarily used to assess cerebrovascular circulation and detect abnormalities such as stenosis (narrowing), occlusion (blockage), or embolism (obstruction) in the intracranial arteries. It can also help monitor patients with conditions like sickle cell disease, vasospasm following subarachnoid hemorrhage, and evaluate the effectiveness of treatments such as thrombolysis or angioplasty. The procedure is typically performed by placing a transducer on the patient's skull after applying a coupling gel, and it does not involve radiation exposure or contrast agents.

Arterial occlusive diseases are medical conditions characterized by the blockage or narrowing of the arteries, which can lead to a reduction in blood flow to various parts of the body. This reduction in blood flow can cause tissue damage and may result in serious complications such as tissue death (gangrene), organ dysfunction, or even death.

The most common cause of arterial occlusive diseases is atherosclerosis, which is the buildup of plaque made up of fat, cholesterol, calcium, and other substances in the inner lining of the artery walls. Over time, this plaque can harden and narrow the arteries, restricting blood flow. Other causes of arterial occlusive diseases include blood clots, emboli (tiny particles that travel through the bloodstream and lodge in smaller vessels), inflammation, trauma, and certain inherited conditions.

Symptoms of arterial occlusive diseases depend on the location and severity of the blockage. Common symptoms include:

* Pain, cramping, or fatigue in the affected limb, often triggered by exercise and relieved by rest (claudication)
* Numbness, tingling, or weakness in the affected limb
* Coldness or discoloration of the skin in the affected area
* Slow-healing sores or wounds on the toes, feet, or legs
* Erectile dysfunction in men

Treatment for arterial occlusive diseases may include lifestyle changes such as quitting smoking, exercising regularly, and eating a healthy diet. Medications to lower cholesterol, control blood pressure, prevent blood clots, or manage pain may also be prescribed. In severe cases, surgical procedures such as angioplasty, stenting, or bypass surgery may be necessary to restore blood flow.

Cerebral revascularization is a surgical procedure aimed at restoring blood flow to the brain. This is often performed in cases where there is narrowing or blockage of the cerebral arteries, a condition known as cerebrovascular disease. The most common type of cerebral revascularization is called carotid endarterectomy, which involves removing plaque buildup from the carotid artery in the neck to improve blood flow to the brain. Another type is extracranial-intracranial bypass, where a new connection is created between an external carotid artery and an intracranial artery to bypass a blockage.

Medical Definition:

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic imaging technique that uses a strong magnetic field and radio waves to create detailed cross-sectional or three-dimensional images of the internal structures of the body. The patient lies within a large, cylindrical magnet, and the scanner detects changes in the direction of the magnetic field caused by protons in the body. These changes are then converted into detailed images that help medical professionals to diagnose and monitor various medical conditions, such as tumors, injuries, or diseases affecting the brain, spinal cord, heart, blood vessels, joints, and other internal organs. MRI does not use radiation like computed tomography (CT) scans.

In epidemiology, the incidence of a disease is defined as the number of new cases of that disease within a specific population over a certain period of time. It is typically expressed as a rate, with the number of new cases in the numerator and the size of the population at risk in the denominator. Incidence provides information about the risk of developing a disease during a given time period and can be used to compare disease rates between different populations or to monitor trends in disease occurrence over time.

"Age factors" refer to the effects, changes, or differences that age can have on various aspects of health, disease, and medical care. These factors can encompass a wide range of issues, including:

1. Physiological changes: As people age, their bodies undergo numerous physical changes that can affect how they respond to medications, illnesses, and medical procedures. For example, older adults may be more sensitive to certain drugs or have weaker immune systems, making them more susceptible to infections.
2. Chronic conditions: Age is a significant risk factor for many chronic diseases, such as heart disease, diabetes, cancer, and arthritis. As a result, age-related medical issues are common and can impact treatment decisions and outcomes.
3. Cognitive decline: Aging can also lead to cognitive changes, including memory loss and decreased decision-making abilities. These changes can affect a person's ability to understand and comply with medical instructions, leading to potential complications in their care.
4. Functional limitations: Older adults may experience physical limitations that impact their mobility, strength, and balance, increasing the risk of falls and other injuries. These limitations can also make it more challenging for them to perform daily activities, such as bathing, dressing, or cooking.
5. Social determinants: Age-related factors, such as social isolation, poverty, and lack of access to transportation, can impact a person's ability to obtain necessary medical care and affect their overall health outcomes.

Understanding age factors is critical for healthcare providers to deliver high-quality, patient-centered care that addresses the unique needs and challenges of older adults. By taking these factors into account, healthcare providers can develop personalized treatment plans that consider a person's age, physical condition, cognitive abilities, and social circumstances.

The Complement Membrane Attack Complex (MAC), also known as the Terminal Complement Complex (TCC), is a protein structure that forms in the final stages of the complement system's immune response. The complement system is a part of the innate immune system that helps to eliminate pathogens and damaged cells from the body.

The MAC is composed of several proteins, including C5b, C6, C7, C8, and multiple subunits of C9, which assemble on the surface of target cells. The formation of the MAC creates a pore-like structure in the cell membrane, leading to disruption of the membrane's integrity and ultimately causing cell lysis or damage.

The MAC plays an important role in the immune response by helping to eliminate pathogens that have evaded other immune defenses. However, uncontrolled activation of the complement system and formation of the MAC can also contribute to tissue damage and inflammation in various diseases, such as autoimmune disorders, age-related macular degeneration, and ischemia-reperfusion injury.

The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:

1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.

The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.

Angiography is a medical procedure in which an x-ray image is taken to visualize the internal structure of blood vessels, arteries, or veins. This is done by injecting a radiopaque contrast agent (dye) into the blood vessel using a thin, flexible catheter. The dye makes the blood vessels visible on an x-ray image, allowing doctors to diagnose and treat various medical conditions such as blockages, narrowing, or malformations of the blood vessels.

There are several types of angiography, including:

* Cardiac angiography (also called coronary angiography) - used to examine the blood vessels of the heart
* Cerebral angiography - used to examine the blood vessels of the brain
* Peripheral angiography - used to examine the blood vessels in the limbs or other parts of the body.

Angiography is typically performed by a radiologist, cardiologist, or vascular surgeon in a hospital setting. It can help diagnose conditions such as coronary artery disease, aneurysms, and peripheral arterial disease, among others.

Intracranial hemorrhage (ICH) is a type of stroke caused by bleeding within the brain or its surrounding tissues. It's a serious medical emergency that requires immediate attention and treatment. The bleeding can occur in various locations:

1. Epidural hematoma: Bleeding between the dura mater (the outermost protective covering of the brain) and the skull. This is often caused by trauma, such as a head injury.
2. Subdural hematoma: Bleeding between the dura mater and the brain's surface, which can also be caused by trauma.
3. Subarachnoid hemorrhage: Bleeding in the subarachnoid space, which is filled with cerebrospinal fluid (CSF) and surrounds the brain. This type of ICH is commonly caused by the rupture of an intracranial aneurysm or arteriovenous malformation.
4. Intraparenchymal hemorrhage: Bleeding within the brain tissue itself, which can be caused by hypertension (high blood pressure), amyloid angiopathy, or trauma.
5. Intraventricular hemorrhage: Bleeding into the brain's ventricular system, which contains CSF and communicates with the subarachnoid space. This type of ICH is often seen in premature infants but can also be caused by head trauma or aneurysm rupture in adults.

Symptoms of intracranial hemorrhage may include sudden severe headache, vomiting, altered consciousness, confusion, seizures, weakness, numbness, or paralysis on one side of the body, vision changes, or difficulty speaking or understanding speech. Rapid diagnosis and treatment are crucial to prevent further brain damage and potential long-term disabilities or death.

Comorbidity is the presence of one or more additional health conditions or diseases alongside a primary illness or condition. These co-occurring health issues can have an impact on the treatment plan, prognosis, and overall healthcare management of an individual. Comorbidities often interact with each other and the primary condition, leading to more complex clinical situations and increased healthcare needs. It is essential for healthcare professionals to consider and address comorbidities to provide comprehensive care and improve patient outcomes.

Carotid artery thrombosis is a medical condition characterized by the formation of a blood clot (thrombus) inside the carotid artery, which is one of the major blood vessels that supplies oxygenated blood to the head and neck. This condition can lead to serious complications such as a stroke or transient ischemic attack (TIA), also known as a "mini-stroke," if the clot dislodges and travels to the brain, blocking the flow of blood and oxygen.

Carotid artery thrombosis can result from various factors, including atherosclerosis (the buildup of fats, cholesterol, and other substances in the artery walls), hypertension (high blood pressure), diabetes, smoking, and genetic predisposition. Symptoms may include neck pain or stiffness, weakness or numbness in the face or limbs, difficulty speaking or understanding speech, vision problems, and sudden severe headaches. Diagnosis typically involves imaging tests such as ultrasound, CT angiography, or MRI angiography. Treatment options may include anticoagulant or antiplatelet medications, endovascular procedures to remove the clot, or surgery to clean out the artery (carotid endarterectomy).

A stent is a small mesh tube that's used to treat narrow or weak arteries. Arteries are blood vessels that carry blood away from your heart to other parts of your body. A stent is placed in an artery as part of a procedure called angioplasty. Angioplasty restores blood flow through narrowed or blocked arteries by inflating a tiny balloon inside the blocked artery to widen it.

The stent is then inserted into the widened artery to keep it open. The stent is usually made of metal, but some are coated with medication that is slowly and continuously released to help prevent the formation of scar tissue in the artery. This can reduce the chance of the artery narrowing again.

Stents are also used in other parts of the body, such as the neck (carotid artery) and kidneys (renal artery), to help maintain blood flow and prevent blockages. They can also be used in the urinary system to treat conditions like ureteropelvic junction obstruction or narrowing of the urethra.

Angioplasty is a medical procedure used to open narrowed or blocked blood vessels, often referred to as coronary angioplasty when it involves the heart's blood vessels (coronary arteries). The term "angio" refers to an angiogram, which is a type of X-ray image that reveals the inside of blood vessels.

The procedure typically involves the following steps:

1. A thin, flexible catheter (tube) is inserted into a blood vessel, usually through a small incision in the groin or arm.
2. The catheter is guided to the narrowed or blocked area using real-time X-ray imaging.
3. Once in place, a tiny balloon attached to the tip of the catheter is inflated to widen the blood vessel and compress any plaque buildup against the artery walls.
4. A stent (a small mesh tube) may be inserted to help keep the blood vessel open and prevent it from narrowing again.
5. The balloon is deflated, and the catheter is removed.

Angioplasty helps improve blood flow, reduce symptoms such as chest pain or shortness of breath, and lower the risk of heart attack in patients with blocked arteries. It's important to note that angioplasty is not a permanent solution for coronary artery disease, and lifestyle changes, medications, and follow-up care are necessary to maintain long-term cardiovascular health.

Ticlopidine is defined as a platelet aggregation inhibitor drug, which works by preventing certain types of blood cells (platelets) from sticking together to form clots. It is used to reduce the risk of stroke and heart attack in patients who have already had a stroke or have peripheral arterial disease.

Ticlopidine is a thienopyridine derivative that selectively inhibits platelet activation and aggregation by blocking the ADP (adenosine diphosphate) receptor on the platelet surface. This action prevents the formation of platelet plugs, which can lead to the development of blood clots in the arteries.

Ticlopidine is available in oral form as tablets and is typically taken twice daily. Common side effects include diarrhea, skin rash, and itching. More serious side effects, such as neutropenia (low white blood cell count), thrombotic thrombocytopenic purpura (TTP), and aplastic anemia, are rare but can be life-threatening.

Due to the risk of serious side effects, ticlopidine is usually reserved for use in patients who cannot tolerate or have failed other antiplatelet therapies, such as aspirin or clopidogrel. It is important to monitor patients taking ticlopidine closely for signs of adverse reactions and to follow the prescribing instructions carefully.

A neurological examination is a series of tests used to evaluate the functioning of the nervous system, including both the central nervous system (the brain and spinal cord) and peripheral nervous system (the nerves that extend from the brain and spinal cord to the rest of the body). It is typically performed by a healthcare professional such as a neurologist or a primary care physician with specialized training in neurology.

During a neurological examination, the healthcare provider will assess various aspects of neurological function, including:

1. Mental status: This involves evaluating a person's level of consciousness, orientation, memory, and cognitive abilities.
2. Cranial nerves: There are 12 cranial nerves that control functions such as vision, hearing, smell, taste, and movement of the face and neck. The healthcare provider will test each of these nerves to ensure they are functioning properly.
3. Motor function: This involves assessing muscle strength, tone, coordination, and reflexes. The healthcare provider may ask the person to perform certain movements or tasks to evaluate these functions.
4. Sensory function: The healthcare provider will test a person's ability to feel different types of sensations, such as touch, pain, temperature, vibration, and proprioception (the sense of where your body is in space).
5. Coordination and balance: The healthcare provider may assess a person's ability to perform coordinated movements, such as touching their finger to their nose or walking heel-to-toe.
6. Reflexes: The healthcare provider will test various reflexes throughout the body using a reflex hammer.

The results of a neurological examination can help healthcare providers diagnose and monitor conditions that affect the nervous system, such as stroke, multiple sclerosis, Parkinson's disease, or peripheral neuropathy.

Ultrasonography, Doppler, and Duplex are diagnostic medical techniques that use sound waves to create images of internal body structures and assess their function. Here are the definitions for each:

1. Ultrasonography: Also known as ultrasound, this is a non-invasive imaging technique that uses high-frequency sound waves to produce images of internal organs and tissues. A small handheld device called a transducer is placed on the skin surface, which emits and receives sound waves. The returning echoes are then processed to create real-time visual images of the internal structures.
2. Doppler: This is a type of ultrasound that measures the velocity and direction of blood flow in the body by analyzing the frequency shift of the reflected sound waves. It can be used to assess blood flow in various parts of the body, such as the heart, arteries, and veins.
3. Duplex: Duplex ultrasonography is a combination of both gray-scale ultrasound and Doppler ultrasound. It provides detailed images of internal structures, as well as information about blood flow velocity and direction. This technique is often used to evaluate conditions such as deep vein thrombosis, carotid artery stenosis, and peripheral arterial disease.

In summary, ultrasonography is a diagnostic imaging technique that uses sound waves to create images of internal structures, Doppler is a type of ultrasound that measures blood flow velocity and direction, and duplex is a combination of both techniques that provides detailed images and information about blood flow.

Intracranial thrombosis refers to the formation of a blood clot (thrombus) within the intracranial vessels, which supply blood to the brain. This condition can occur in any of the cerebral arteries or veins and can lead to serious complications such as ischemic stroke, transient ischemic attack (TIA), or venous sinus thrombosis.

The formation of an intracranial thrombus can be caused by various factors, including atherosclerosis, cardiac embolism, vasculitis, sickle cell disease, hypercoagulable states, and head trauma. Symptoms may vary depending on the location and extent of the thrombosis but often include sudden onset of headache, weakness or numbness in the face or limbs, difficulty speaking or understanding speech, vision changes, and loss of balance or coordination.

Diagnosis of intracranial thrombosis typically involves imaging studies such as computed tomography (CT) angiography, magnetic resonance angiography (MRA), or digital subtraction angiography (DSA). Treatment options may include anticoagulation therapy, thrombolysis, endovascular intervention, or surgical intervention, depending on the underlying cause and severity of the condition.

Postoperative complications refer to any unfavorable condition or event that occurs during the recovery period after a surgical procedure. These complications can vary in severity and may include, but are not limited to:

1. Infection: This can occur at the site of the incision or inside the body, such as pneumonia or urinary tract infection.
2. Bleeding: Excessive bleeding (hemorrhage) can lead to a drop in blood pressure and may require further surgical intervention.
3. Blood clots: These can form in the deep veins of the legs (deep vein thrombosis) and can potentially travel to the lungs (pulmonary embolism).
4. Wound dehiscence: This is when the surgical wound opens up, which can lead to infection and further complications.
5. Pulmonary issues: These include atelectasis (collapsed lung), pneumonia, or respiratory failure.
6. Cardiovascular problems: These include abnormal heart rhythms (arrhythmias), heart attack, or stroke.
7. Renal failure: This can occur due to various reasons such as dehydration, blood loss, or the use of certain medications.
8. Pain management issues: Inadequate pain control can lead to increased stress, anxiety, and decreased mobility.
9. Nausea and vomiting: These can be caused by anesthesia, opioid pain medication, or other factors.
10. Delirium: This is a state of confusion and disorientation that can occur in the elderly or those with certain medical conditions.

Prompt identification and management of these complications are crucial to ensure the best possible outcome for the patient.

A Severity of Illness Index is a measurement tool used in healthcare to assess the severity of a patient's condition and the risk of mortality or other adverse outcomes. These indices typically take into account various physiological and clinical variables, such as vital signs, laboratory values, and co-morbidities, to generate a score that reflects the patient's overall illness severity.

Examples of Severity of Illness Indices include the Acute Physiology and Chronic Health Evaluation (APACHE) system, the Simplified Acute Physiology Score (SAPS), and the Mortality Probability Model (MPM). These indices are often used in critical care settings to guide clinical decision-making, inform prognosis, and compare outcomes across different patient populations.

It is important to note that while these indices can provide valuable information about a patient's condition, they should not be used as the sole basis for clinical decision-making. Rather, they should be considered in conjunction with other factors, such as the patient's overall clinical presentation, treatment preferences, and goals of care.

An acute disease is a medical condition that has a rapid onset, develops quickly, and tends to be short in duration. Acute diseases can range from minor illnesses such as a common cold or flu, to more severe conditions such as pneumonia, meningitis, or a heart attack. These types of diseases often have clear symptoms that are easy to identify, and they may require immediate medical attention or treatment.

Acute diseases are typically caused by an external agent or factor, such as a bacterial or viral infection, a toxin, or an injury. They can also be the result of a sudden worsening of an existing chronic condition. In general, acute diseases are distinct from chronic diseases, which are long-term medical conditions that develop slowly over time and may require ongoing management and treatment.

Examples of acute diseases include:

* Acute bronchitis: a sudden inflammation of the airways in the lungs, often caused by a viral infection.
* Appendicitis: an inflammation of the appendix that can cause severe pain and requires surgical removal.
* Gastroenteritis: an inflammation of the stomach and intestines, often caused by a viral or bacterial infection.
* Migraine headaches: intense headaches that can last for hours or days, and are often accompanied by nausea, vomiting, and sensitivity to light and sound.
* Myocardial infarction (heart attack): a sudden blockage of blood flow to the heart muscle, often caused by a buildup of plaque in the coronary arteries.
* Pneumonia: an infection of the lungs that can cause coughing, chest pain, and difficulty breathing.
* Sinusitis: an inflammation of the sinuses, often caused by a viral or bacterial infection.

It's important to note that while some acute diseases may resolve on their own with rest and supportive care, others may require medical intervention or treatment to prevent complications and promote recovery. If you are experiencing symptoms of an acute disease, it is always best to seek medical attention to ensure proper diagnosis and treatment.

Dipyridamole is a medication that belongs to a class of drugs called antiplatelet agents. It works by preventing platelets in your blood from sticking together to form clots. Dipyridamole is often used in combination with aspirin to prevent stroke and other complications in people who have had a heart valve replacement or a type of irregular heartbeat called atrial fibrillation.

Dipyridamole can also be used as a stress agent in myocardial perfusion imaging studies, which are tests used to evaluate blood flow to the heart. When used for this purpose, dipyridamole is given intravenously and works by dilating the blood vessels in the heart, allowing more blood to flow through them and making it easier to detect areas of reduced blood flow.

The most common side effects of dipyridamole include headache, dizziness, and gastrointestinal symptoms such as diarrhea, nausea, and vomiting. In rare cases, dipyridamole can cause more serious side effects, such as allergic reactions, abnormal heart rhythms, or low blood pressure. It is important to take dipyridamole exactly as directed by your healthcare provider and to report any unusual symptoms or side effects promptly.

A registry in the context of medicine is a collection or database of standardized information about individuals who share a certain condition or attribute, such as a disease, treatment, exposure, or demographic group. These registries are used for various purposes, including:

* Monitoring and tracking the natural history of diseases and conditions
* Evaluating the safety and effectiveness of medical treatments and interventions
* Conducting research and generating hypotheses for further study
* Providing information to patients, clinicians, and researchers
* Informing public health policy and decision-making

Registries can be established for a wide range of purposes, including disease-specific registries (such as cancer or diabetes registries), procedure-specific registries (such as joint replacement or cardiac surgery registries), and population-based registries (such as birth defects or cancer registries). Data collected in registries may include demographic information, clinical data, laboratory results, treatment details, and outcomes.

Registries can be maintained by a variety of organizations, including hospitals, clinics, academic medical centers, professional societies, government agencies, and industry. Participation in registries is often voluntary, although some registries may require informed consent from participants. Data collected in registries are typically de-identified to protect the privacy of individuals.

Pathological constriction refers to an abnormal narrowing or tightening of a body passage or organ, which can interfere with the normal flow of blood, air, or other substances through the area. This constriction can occur due to various reasons such as inflammation, scarring, or abnormal growths, and can affect different parts of the body, including blood vessels, airways, intestines, and ureters. Pathological constriction can lead to a range of symptoms and complications depending on its location and severity, and may require medical intervention to correct.

Hypertension is a medical term used to describe abnormally high blood pressure in the arteries, often defined as consistently having systolic blood pressure (the top number in a blood pressure reading) over 130 mmHg and/or diastolic blood pressure (the bottom number) over 80 mmHg. It is also commonly referred to as high blood pressure.

Hypertension can be classified into two types: primary or essential hypertension, which has no identifiable cause and accounts for about 95% of cases, and secondary hypertension, which is caused by underlying medical conditions such as kidney disease, hormonal disorders, or use of certain medications.

If left untreated, hypertension can lead to serious health complications such as heart attack, stroke, heart failure, and chronic kidney disease. Therefore, it is important for individuals with hypertension to manage their condition through lifestyle modifications (such as healthy diet, regular exercise, stress management) and medication if necessary, under the guidance of a healthcare professional.

Blindness is a condition of complete or near-complete vision loss. It can be caused by various factors such as eye diseases, injuries, or birth defects. Total blindness means that a person cannot see anything at all, while near-complete blindness refers to having only light perception or the ability to perceive the direction of light, but not able to discern shapes or forms. Legal blindness is a term used to define a certain level of visual impairment that qualifies an individual for government assistance and benefits; it usually means best corrected visual acuity of 20/200 or worse in the better eye, or a visual field no greater than 20 degrees in diameter.

Prognosis is a medical term that refers to the prediction of the likely outcome or course of a disease, including the chances of recovery or recurrence, based on the patient's symptoms, medical history, physical examination, and diagnostic tests. It is an important aspect of clinical decision-making and patient communication, as it helps doctors and patients make informed decisions about treatment options, set realistic expectations, and plan for future care.

Prognosis can be expressed in various ways, such as percentages, categories (e.g., good, fair, poor), or survival rates, depending on the nature of the disease and the available evidence. However, it is important to note that prognosis is not an exact science and may vary depending on individual factors, such as age, overall health status, and response to treatment. Therefore, it should be used as a guide rather than a definitive forecast.

Vascular diseases are medical conditions that affect the circulatory system, specifically the blood vessels (arteries, veins, and capillaries). These diseases can include conditions such as:

1. Atherosclerosis: The buildup of fats, cholesterol, and other substances in and on the walls of the arteries, which can restrict blood flow.
2. Peripheral Artery Disease (PAD): A condition caused by atherosclerosis where there is narrowing or blockage of the peripheral arteries, most commonly in the legs. This can lead to pain, numbness, and cramping.
3. Coronary Artery Disease (CAD): Atherosclerosis of the coronary arteries that supply blood to the heart muscle. This can lead to chest pain, shortness of breath, or a heart attack.
4. Carotid Artery Disease: Atherosclerosis of the carotid arteries in the neck that supply blood to the brain. This can increase the risk of stroke.
5. Cerebrovascular Disease: Conditions that affect blood flow to the brain, including stroke and transient ischemic attack (TIA or "mini-stroke").
6. Aneurysm: A weakened area in the wall of a blood vessel that causes it to bulge outward and potentially rupture.
7. Deep Vein Thrombosis (DVT): A blood clot that forms in the deep veins, usually in the legs, which can cause pain, swelling, and increased risk of pulmonary embolism if the clot travels to the lungs.
8. Varicose Veins: Swollen, twisted, and often painful veins that have filled with an abnormal collection of blood, usually appearing in the legs.
9. Vasculitis: Inflammation of the blood vessels, which can cause damage and narrowing, leading to reduced blood flow.
10. Raynaud's Phenomenon: A condition where the small arteries that supply blood to the skin become narrowed, causing decreased blood flow, typically in response to cold temperatures or stress.

These are just a few examples of vascular conditions that fall under the umbrella term "cerebrovascular disease." Early diagnosis and treatment can significantly improve outcomes for many of these conditions.

Transesophageal echocardiography (TEE) is a type of echocardiogram, which is a medical test that uses sound waves to create detailed images of the heart. In TEE, a special probe containing a transducer is passed down the esophagus (the tube that connects the mouth to the stomach) to obtain views of the heart from behind. This allows for more detailed images of the heart structures and function compared to a standard echocardiogram, which uses a probe placed on the chest. TEE is often used in patients with poor image quality from a standard echocardiogram or when more detailed images are needed to diagnose or monitor certain heart conditions. It is typically performed by a trained cardiologist or sonographer under the direction of a cardiologist.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

Brain infarction, also known as cerebral infarction, is a type of stroke that occurs when blood flow to a part of the brain is blocked, often by a blood clot. This results in oxygen and nutrient deprivation to the brain tissue, causing it to become damaged or die. The effects of a brain infarction depend on the location and extent of the damage, but can include weakness, numbness, paralysis, speech difficulties, memory loss, and other neurological symptoms.

Brain infarctions are often caused by underlying medical conditions such as atherosclerosis, atrial fibrillation, or high blood pressure. Treatment typically involves addressing the underlying cause of the blockage, administering medications to dissolve clots or prevent further clotting, and providing supportive care to manage symptoms and prevent complications.

I'm sorry for any confusion, but "September 11 Terrorist Attacks" is a historical event rather than a medical condition or term. Therefore, it doesn't have a specific medical definition. However, I can provide some context:

The September 11 Terrorist Attacks, often referred to as 9/11, were a series of coordinated terrorist attacks that occurred in the United States on September 11, 2001. These attacks were carried out by the Islamic extremist group al-Qaeda. The attacks involved the hijacking of four commercial airplanes. Two of these planes were flown into the Twin Towers of the World Trade Center complex in New York City, causing both towers to collapse within hours. Another plane hit the Pentagon building in Arlington, Virginia, and the fourth crashed in a field in Pennsylvania after passengers attempted to overcome the hijackers.

The attacks resulted in thousands of deaths and injuries, making it one of the deadliest terrorist attacks in world history. The physical and psychological health effects were significant and far-reaching, affecting not only the survivors and first responders but also the nation as a whole. These effects included acute trauma reactions, post-traumatic stress disorder (PTSD), depression, anxiety, and various physical health issues.

While "September 11 Terrorist Attacks" is not a medical term, it is associated with numerous mental and physical health issues that have been studied and documented in the medical and psychological literature.

Heart disease is a broad term for a class of diseases that involve the heart or blood vessels. It's often used to refer to conditions that include:

1. Coronary artery disease (CAD): This is the most common type of heart disease. It occurs when the arteries that supply blood to the heart become hardened and narrowed due to the buildup of cholesterol and other substances, which can lead to chest pain (angina), shortness of breath, or a heart attack.

2. Heart failure: This condition occurs when the heart is unable to pump blood efficiently to meet the body's needs. It can be caused by various conditions, including coronary artery disease, high blood pressure, and cardiomyopathy.

3. Arrhythmias: These are abnormal heart rhythms, which can be too fast, too slow, or irregular. They can lead to symptoms such as palpitations, dizziness, and fainting.

4. Valvular heart disease: This involves damage to one or more of the heart's four valves, which control blood flow through the heart. Damage can be caused by various conditions, including infection, rheumatic fever, and aging.

5. Cardiomyopathy: This is a disease of the heart muscle that makes it harder for the heart to pump blood efficiently. It can be caused by various factors, including genetics, viral infections, and drug abuse.

6. Pericardial disease: This involves inflammation or other problems with the sac surrounding the heart (pericardium). It can cause chest pain and other symptoms.

7. Congenital heart defects: These are heart conditions that are present at birth, such as a hole in the heart or abnormal blood vessels. They can range from mild to severe and may require medical intervention.

8. Heart infections: The heart can become infected by bacteria, viruses, or parasites, leading to various symptoms and complications.

It's important to note that many factors can contribute to the development of heart disease, including genetics, lifestyle choices, and certain medical conditions. Regular check-ups and a healthy lifestyle can help reduce the risk of developing heart disease.

Ultrasonography, also known as sonography, is a diagnostic medical procedure that uses high-frequency sound waves (ultrasound) to produce dynamic images of organs, tissues, or blood flow inside the body. These images are captured in real-time and can be used to assess the size, shape, and structure of various internal structures, as well as detect any abnormalities such as tumors, cysts, or inflammation.

During an ultrasonography procedure, a small handheld device called a transducer is placed on the patient's skin, which emits and receives sound waves. The transducer sends high-frequency sound waves into the body, and these waves bounce back off internal structures and are recorded by the transducer. The recorded data is then processed and transformed into visual images that can be interpreted by a medical professional.

Ultrasonography is a non-invasive, painless, and safe procedure that does not use radiation like other imaging techniques such as CT scans or X-rays. It is commonly used to diagnose and monitor conditions in various parts of the body, including the abdomen, pelvis, heart, blood vessels, and musculoskeletal system.

Fibromuscular dysplasia (FMD) is a rare condition that affects the arterial walls, primarily in the medium and large-sized arteries. According to the American Heart Association, FMD is characterized by uneven growth or damage to the cells in the artery wall, leading to the formation of fibrous tissue and areas with narrowing (stenosis) or ballooning (aneurysm) of the artery.

FMD most commonly affects the renal (kidney) and carotid (neck) arteries but can also occur in other arteries, such as those in the abdomen, arms, and legs. The exact cause of FMD is unknown, but genetic factors and hormonal influences are believed to play a role.

Symptoms of FMD depend on which arteries are affected and may include high blood pressure, headaches, neck pain, dizziness, visual disturbances, or kidney problems. Diagnosis typically involves imaging tests like ultrasound, CT angiography, or magnetic resonance angiography (MRA). Treatment options for FMD include medications to manage symptoms and control high blood pressure, as well as various interventions such as angioplasty or stenting to open narrowed arteries.

Thromboembolism is a medical condition that refers to the obstruction of a blood vessel by a thrombus (blood clot) that has formed elsewhere in the body and then been transported by the bloodstream to a narrower vessel, where it becomes lodged. This process can occur in various parts of the body, leading to different types of thromboembolisms:

1. Deep Vein Thrombosis (DVT): A thrombus forms in the deep veins, usually in the legs or pelvis, and then breaks off and travels to the lungs, causing a pulmonary embolism.
2. Pulmonary Embolism (PE): A thrombus formed elsewhere, often in the deep veins of the legs, dislodges and travels to the lungs, blocking one or more pulmonary arteries. This can lead to shortness of breath, chest pain, and potentially life-threatening complications if not treated promptly.
3. Cerebral Embolism: A thrombus formed in another part of the body, such as the heart or carotid artery, dislodges and travels to the brain, causing a stroke or transient ischemic attack (TIA).
4. Arterial Thromboembolism: A thrombus forms in an artery and breaks off, traveling to another part of the body and blocking blood flow to an organ or tissue, leading to potential damage or loss of function. Examples include mesenteric ischemia (intestinal damage due to blocked blood flow) and retinal artery occlusion (vision loss due to blocked blood flow in the eye).

Prevention, early detection, and appropriate treatment are crucial for managing thromboembolism and reducing the risk of severe complications.

Paradoxical embolism is a medical condition that occurs when a blood clot or other material (embolus) from a vein passes through an abnormal connection between the right and left sides of the heart and lodges in an artery in the systemic circulation. This is considered "paradoxical" because the embolus originates from the venous system but bypasses the lungs and travels directly to the arterial system.

Under normal circumstances, blood flows from the body's veins into the right atrium of the heart, then through the tricuspid valve into the right ventricle, where it is pumped through the pulmonary artery into the lungs for oxygenation. The now oxygen-rich blood returns to the left atrium via the pulmonary veins, passes through the mitral valve into the left ventricle, and is then pumped out to the body's arteries.

However, in certain conditions such as a patent foramen ovale (PFO) or an atrial septal defect (ASD), there can be an abnormal communication between the right and left atria. This allows for the possibility of a paradoxical embolism to occur when a clot or other material from the venous system passes through this connection into the arterial system, bypassing filtration and oxygenation in the lungs.

Paradoxical embolism can lead to serious consequences, such as stroke, transient ischemic attack (TIA), or tissue damage in various organs, depending on where the embolus lodges. Treatment typically involves addressing the underlying cause of the paradoxical embolism and may include anticoagulation therapy, surgical closure of the abnormal connection, or other interventions as necessary.

Fibrinolytic agents are medications that dissolve or break down blood clots by activating plasminogen, which is converted into plasmin. Plasmin is a proteolytic enzyme that degrades fibrin, the structural protein in blood clots. Fibrinolytic agents are used medically to treat conditions such as acute ischemic stroke, deep vein thrombosis, pulmonary embolism, and myocardial infarction (heart attack) by restoring blood flow in occluded vessels. Examples of fibrinolytic agents include alteplase, reteplase, and tenecteplase. It is important to note that these medications carry a risk of bleeding complications and should be administered with caution.

Angioplasty, balloon refers to a medical procedure used to widen narrowed or obstructed blood vessels, particularly the coronary arteries that supply blood to the heart muscle. This procedure is typically performed using a catheter-based technique, where a thin, flexible tube called a catheter is inserted into an artery, usually through the groin or wrist, and guided to the site of the narrowing or obstruction in the coronary artery.

Once the catheter reaches the affected area, a small balloon attached to the tip of the catheter is inflated, which compresses the plaque against the artery wall and stretches the artery, thereby restoring blood flow. The balloon is then deflated and removed, along with the catheter.

Balloon angioplasty is often combined with the placement of a stent, a small metal mesh tube that helps to keep the artery open and prevent it from narrowing again. This procedure is known as percutaneous coronary intervention (PCI) or coronary angioplasty and stenting.

Overall, balloon angioplasty is a relatively safe and effective treatment for coronary artery disease, although complications such as bleeding, infection, or re-narrowing of the artery can occur in some cases.

Triage is a medical term that refers to the process of prioritizing patients based on the severity of their condition or illness, and the resources available. The goal of triage is to ensure that the most critical patients receive care first, which can help reduce morbidity and mortality in emergency situations. This process is typically used in settings where there are more patients than can be treated immediately, such as during mass casualty incidents or in busy emergency departments. Triage nurses or doctors quickly assess each patient's condition, often using a standardized system, to determine the urgency of their medical needs and allocate resources accordingly.

Ophthalmodynamometry is a medical technique used to measure the amount of pressure or force required to flatten the cornea, which can help in the diagnosis and evaluation of various eye conditions, particularly glaucoma. It involves using a handheld device called an ophthalmodynamometer to apply gentle pressure to the eyelid while observing changes in the optic nerve head and retinal vessels through an ophthalmoscope. The test provides information about the resistance of the eyeball to external pressure, which can be useful in assessing the functioning of the eye's aqueous humor drainage system and identifying any abnormalities that may contribute to increased intraocular pressure (IOP).

The procedure typically involves several steps:

1. The patient is asked to look in different directions while the examiner observes the optic nerve head and retinal vessels through an ophthalmoscope.
2. The examiner then applies gentle pressure to the eyelid using the ophthalmodynamometer, gradually increasing the force until the cornea begins to flatten.
3. The amount of pressure required to achieve this is recorded as the ophthalmodynamometric value.
4. The examiner may repeat the process several times to ensure accurate and consistent results.
5. The results are then compared with normative data to determine whether the patient's IOP is within normal limits or if there are any signs of glaucoma or other eye conditions.

It is important to note that ophthalmodynamometry should only be performed by trained healthcare professionals, as improper technique can lead to inaccurate results and potential harm to the patient's eyes.

Arteriosclerosis is a general term that describes the hardening and stiffening of the artery walls. It's a progressive condition that can occur as a result of aging, or it may be associated with certain risk factors such as high blood pressure, high cholesterol, diabetes, smoking, and a sedentary lifestyle.

The process of arteriosclerosis involves the buildup of plaque, made up of fat, cholesterol, calcium, and other substances, in the inner lining of the artery walls. Over time, this buildup can cause the artery walls to thicken and harden, reducing the flow of oxygen-rich blood to the body's organs and tissues.

Arteriosclerosis can affect any of the body's arteries, but it is most commonly found in the coronary arteries that supply blood to the heart, the cerebral arteries that supply blood to the brain, and the peripheral arteries that supply blood to the limbs. When arteriosclerosis affects the coronary arteries, it can lead to heart disease, angina, or heart attack. When it affects the cerebral arteries, it can lead to stroke or transient ischemic attack (TIA). When it affects the peripheral arteries, it can cause pain, numbness, or weakness in the limbs, and in severe cases, gangrene and amputation.

The vertebral artery is a major blood vessel that supplies oxygenated blood to the brain and upper spinal cord. It arises from the subclavian artery, then ascends through the transverse processes of several cervical vertebrae before entering the skull through the foramen magnum. Inside the skull, it joins with the opposite vertebral artery to form the basilar artery, which supplies blood to the brainstem and cerebellum. The vertebral artery also gives off several important branches that supply blood to various regions of the brainstem and upper spinal cord.

Myocardial infarction (MI), also known as a heart attack, is a medical condition characterized by the death of a segment of heart muscle (myocardium) due to the interruption of its blood supply. This interruption is most commonly caused by the blockage of a coronary artery by a blood clot formed on the top of an atherosclerotic plaque, which is a buildup of cholesterol and other substances in the inner lining of the artery.

The lack of oxygen and nutrients supply to the heart muscle tissue results in damage or death of the cardiac cells, causing the affected area to become necrotic. The extent and severity of the MI depend on the size of the affected area, the duration of the occlusion, and the presence of collateral circulation.

Symptoms of a myocardial infarction may include chest pain or discomfort, shortness of breath, nausea, lightheadedness, and sweating. Immediate medical attention is necessary to restore blood flow to the affected area and prevent further damage to the heart muscle. Treatment options for MI include medications, such as thrombolytics, antiplatelet agents, and pain relievers, as well as procedures such as percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG).

I'm sorry for any confusion, but "terrorism" is not a term that has a specific medical definition. It is a concept that is typically defined within the contexts of criminal law, international relations, and political science. Generally, terrorism refers to the use of violence or threat of violence, especially against civilians, in the pursuit of political, religious, or ideological objectives. If you have any questions related to medicine or health, I'd be happy to try to help answer those for you!

"Sex factors" is a term used in medicine and epidemiology to refer to the differences in disease incidence, prevalence, or response to treatment that are observed between males and females. These differences can be attributed to biological differences such as genetics, hormones, and anatomy, as well as social and cultural factors related to gender.

For example, some conditions such as autoimmune diseases, depression, and osteoporosis are more common in women, while others such as cardiovascular disease and certain types of cancer are more prevalent in men. Additionally, sex differences have been observed in the effectiveness and side effects of various medications and treatments.

It is important to consider sex factors in medical research and clinical practice to ensure that patients receive appropriate and effective care.

Mitral valve prolapse (MVP) is a heart condition where the mitral valve, which separates the left atrium and left ventricle in the heart, doesn't function properly. In MVP, one or both of the mitral valve flaps (known as leaflets) bulge or billow into the left atrium during the contraction of the left ventricle. This prolapse can cause a leakage of blood back into the atrium, known as mitral regurgitation. In many cases, MVP is asymptomatic and doesn't require treatment, but in some instances, it may lead to complications such as infective endocarditis or arrhythmias. The exact causes of MVP are not fully understood, but it can be associated with certain genetic factors, connective tissue disorders, and mitral valve abnormalities present at birth.

Diabetes complications refer to a range of health issues that can develop as a result of poorly managed diabetes over time. These complications can affect various parts of the body and can be classified into two main categories: macrovascular and microvascular.

Macrovascular complications include:

* Cardiovascular disease (CVD): People with diabetes are at an increased risk of developing CVD, including coronary artery disease, peripheral artery disease, and stroke.
* Peripheral arterial disease (PAD): This condition affects the blood vessels that supply oxygen and nutrients to the limbs, particularly the legs. PAD can cause pain, numbness, or weakness in the legs and may increase the risk of amputation.

Microvascular complications include:

* Diabetic neuropathy: This is a type of nerve damage that can occur due to prolonged high blood sugar levels. It commonly affects the feet and legs, causing symptoms such as numbness, tingling, or pain.
* Diabetic retinopathy: This condition affects the blood vessels in the eye and can cause vision loss or blindness if left untreated.
* Diabetic nephropathy: This is a type of kidney damage that can occur due to diabetes. It can lead to kidney failure if not managed properly.

Other complications of diabetes include:

* Increased risk of infections, particularly skin and urinary tract infections.
* Slow healing of wounds, which can increase the risk of infection and amputation.
* Gum disease and other oral health problems.
* Hearing impairment.
* Sexual dysfunction.

Preventing or managing diabetes complications involves maintaining good blood sugar control, regular monitoring of blood glucose levels, following a healthy lifestyle, and receiving routine medical care.

The atrial appendage, also known as the left atrial appendage (LAA), is a small, ear-shaped structure that is located on the upper left chamber of the heart (left atrium). It has a unique muscular structure and plays a role in the normal functioning of the heart. However, it is best known for its association with atrial fibrillation, a common type of irregular heart rhythm. In people with atrial fibrillation, blood clots can form in the LAA, which can then travel to other parts of the body and cause strokes. For this reason, one treatment option for atrial fibrillation is to close off or remove the LAA to reduce the risk of stroke.

Acetazolamide is a medication that belongs to a class of drugs called carbonic anhydrase inhibitors. It works by decreasing the production of bicarbonate in the body, which helps to reduce the amount of fluid in the eye and brain, making it useful for treating conditions such as glaucoma and epilepsy.

In medical terms, acetazolamide can be defined as: "A carbonic anhydrase inhibitor that is used to treat glaucoma, epilepsy, altitude sickness, and other conditions. It works by decreasing the production of bicarbonate in the body, which helps to reduce the amount of fluid in the eye and brain."

Acetazolamide may also be used for other purposes not listed here, so it is important to consult with a healthcare provider for specific medical advice.

A headache is defined as pain or discomfort in the head, scalp, or neck. It can be a symptom of various underlying conditions such as stress, sinus congestion, migraine, or more serious issues like meningitis or concussion. Headaches can vary in intensity, ranging from mild to severe, and may be accompanied by other symptoms such as nausea, vomiting, or sensitivity to light and sound. There are over 150 different types of headaches, including tension headaches, cluster headaches, and sinus headaches, each with their own specific characteristics and causes.

The odds ratio (OR) is a statistical measure used in epidemiology and research to estimate the association between an exposure and an outcome. It represents the odds that an event will occur in one group versus the odds that it will occur in another group, assuming that all other factors are held constant.

In medical research, the odds ratio is often used to quantify the strength of the relationship between a risk factor (exposure) and a disease outcome. An OR of 1 indicates no association between the exposure and the outcome, while an OR greater than 1 suggests that there is a positive association between the two. Conversely, an OR less than 1 implies a negative association.

It's important to note that the odds ratio is not the same as the relative risk (RR), which compares the incidence rates of an outcome in two groups. While the OR can approximate the RR when the outcome is rare, they are not interchangeable and can lead to different conclusions about the association between an exposure and an outcome.

I'm sorry for any confusion, but "Polyethylene Terephthalates" is not a medical term. It is a type of polymer used in the manufacturing of various products, such as plastic bottles and textile fibers. Medically, you might encounter the abbreviation "PET" or "PET scan," which stands for "Positron Emission Tomography." A PET scan is a type of medical imaging that provides detailed pictures of the body's interior. If you have any medical terms you would like defined, I'd be happy to help!

I apologize, but "Berlin" is not a medical term or condition. Berlin is the capital and largest city of Germany, known for its rich history, culture, and scientific contributions. It does not have a specific medical definition. If you have any questions related to medical conditions or terminology, I would be happy to try to help answer those for you.

Paresis is a medical term that refers to a partial loss of voluntary muscle function. It is often described as muscle weakness, and it can affect one or several parts of the body. Paresis can be caused by various conditions, including nerve damage, stroke, spinal cord injuries, multiple sclerosis, and infections like polio or botulism. The severity of paresis can range from mild to severe, depending on the underlying cause and the specific muscles involved. Treatment for paresis typically focuses on addressing the underlying condition causing it.

Xenon radioisotopes are unstable isotopes of the element xenon that emit radiation as they decay into more stable forms. These isotopes can be produced through various nuclear reactions and have a wide range of applications, including medical imaging and cancer treatment. Examples of commonly used xenon radioisotopes include xenon-127, xenon-131m, xenon-133, and xenon-135.

It's important to note that the use of radioisotopes in medical settings must be carefully regulated and monitored to ensure safety and minimize potential risks to patients and healthcare workers.

Vitamin B Complex refers to a group of water-soluble vitamins that play essential roles in cell metabolism, cellular function, and formation of red blood cells. This complex includes 8 distinct vitamins, all of which were originally thought to be the same vitamin when first discovered. They are now known to have individual structures and specific functions.

1. Vitamin B1 (Thiamin): Necessary for energy production and nerve function.
2. Vitamin B2 (Riboflavin): Involved in energy production and growth.
3. Vitamin B3 (Niacin): Assists in energy production, DNA repair, and acts as a co-factor for various enzymes.
4. Vitamin B5 (Pantothenic Acid): Plays a role in the synthesis of Coenzyme A, which is vital for fatty acid metabolism.
5. Vitamin B6 (Pyridoxine): Needed for protein metabolism, neurotransmitter synthesis, hemoglobin formation, and immune function.
6. Vitamin B7 (Biotin): Involved in fatty acid synthesis, glucose metabolism, and nail and hair health.
7. Vitamin B9 (Folate or Folic Acid): Essential for DNA replication, cell division, and the production of red blood cells.
8. Vitamin B12 (Cobalamin): Necessary for nerve function, DNA synthesis, and the production of red blood cells.

These vitamins are often found together in various foods, and a balanced diet usually provides sufficient amounts of each. Deficiencies can lead to specific health issues related to the functions of each particular vitamin.

Multivariate analysis is a statistical method used to examine the relationship between multiple independent variables and a dependent variable. It allows for the simultaneous examination of the effects of two or more independent variables on an outcome, while controlling for the effects of other variables in the model. This technique can be used to identify patterns, associations, and interactions among multiple variables, and is commonly used in medical research to understand complex health outcomes and disease processes. Examples of multivariate analysis methods include multiple regression, factor analysis, cluster analysis, and discriminant analysis.

The external carotid artery is a major blood vessel in the neck that supplies oxygenated blood to the structures of the head and neck, excluding the brain. It originates from the common carotid artery at the level of the upper border of the thyroid cartilage, then divides into several branches that supply various regions of the head and neck, including the face, scalp, ears, and neck muscles.

The external carotid artery has eight branches:

1. Superior thyroid artery: Supplies blood to the thyroid gland, larynx, and surrounding muscles.
2. Ascending pharyngeal artery: Supplies blood to the pharynx, palate, and meninges of the brain.
3. Lingual artery: Supplies blood to the tongue and floor of the mouth.
4. Facial artery: Supplies blood to the face, nose, lips, and palate.
5. Occipital artery: Supplies blood to the scalp and muscles of the neck.
6. Posterior auricular artery: Supplies blood to the ear and surrounding muscles.
7. Maxillary artery: Supplies blood to the lower face, nasal cavity, palate, and meninges of the brain.
8. Superficial temporal artery: Supplies blood to the scalp, face, and temporomandibular joint.

The external carotid artery is an essential structure for maintaining adequate blood flow to the head and neck, and any damage or blockage can lead to serious medical conditions such as stroke or tissue necrosis.

A randomized controlled trial (RCT) is a type of clinical study in which participants are randomly assigned to receive either the experimental intervention or the control condition, which may be a standard of care, placebo, or no treatment. The goal of an RCT is to minimize bias and ensure that the results are due to the intervention being tested rather than other factors. This design allows for a comparison between the two groups to determine if there is a significant difference in outcomes. RCTs are often considered the gold standard for evaluating the safety and efficacy of medical interventions, as they provide a high level of evidence for causal relationships between the intervention and health outcomes.

Hemorrhage is defined in the medical context as an excessive loss of blood from the circulatory system, which can occur due to various reasons such as injury, surgery, or underlying health conditions that affect blood clotting or the integrity of blood vessels. The bleeding may be internal, external, visible, or concealed, and it can vary in severity from minor to life-threatening, depending on the location and extent of the bleeding. Hemorrhage is a serious medical emergency that requires immediate attention and treatment to prevent further blood loss, organ damage, and potential death.

Proportional hazards models are a type of statistical analysis used in medical research to investigate the relationship between covariates (predictor variables) and survival times. The most common application of proportional hazards models is in the Cox regression model, which is named after its developer, Sir David Cox.

In a proportional hazards model, the hazard rate or risk of an event occurring at a given time is assumed to be proportional to the hazard rate of a reference group, after adjusting for the covariates. This means that the ratio of the hazard rates between any two individuals remains constant over time, regardless of their survival times.

Mathematically, the hazard function h(t) at time t for an individual with a set of covariates X can be expressed as:

h(t|X) = h0(t) \* exp(β1X1 + β2X2 + ... + βpXp)

where h0(t) is the baseline hazard function, X1, X2, ..., Xp are the covariates, and β1, β2, ..., βp are the regression coefficients that represent the effect of each covariate on the hazard rate.

The assumption of proportionality is crucial in the interpretation of the results from a Cox regression model. If the assumption is violated, then the estimated regression coefficients may be biased and misleading. Therefore, it is important to test for the proportional hazards assumption before interpreting the results of a Cox regression analysis.

Dizziness is a term used to describe a range of sensations, such as feeling lightheaded, faint, unsteady, or a false sense of spinning or moving. Medically, dizziness is often described as a non-specific symptom that can be caused by various underlying conditions or factors. These may include:

1. Inner ear disorders (such as benign paroxysmal positional vertigo, labyrinthitis, vestibular neuronitis, or Meniere's disease)
2. Cardiovascular problems (like low blood pressure, arrhythmias, or orthostatic hypotension)
3. Neurological issues (such as migraines, multiple sclerosis, or stroke)
4. Anxiety disorders and panic attacks
5. Side effects of medications
6. Dehydration or overheating
7. Infections (like viral infections or bacterial meningitis)
8. Head or neck injuries
9. Low blood sugar levels (hypoglycemia)

It is essential to consult a healthcare professional if you experience persistent dizziness, as it can be a sign of a more severe underlying condition. The appropriate treatment will depend on the specific cause of the dizziness.

Early diagnosis refers to the identification and detection of a medical condition or disease in its initial stages, before the appearance of significant symptoms or complications. This is typically accomplished through various screening methods, such as medical history reviews, physical examinations, laboratory tests, and imaging studies. Early diagnosis can allow for more effective treatment interventions, potentially improving outcomes and quality of life for patients, while also reducing the overall burden on healthcare systems.

Nervous system diseases, also known as neurological disorders, refer to a group of conditions that affect the nervous system, which includes the brain, spinal cord, nerves, and muscles. These diseases can affect various functions of the body, such as movement, sensation, cognition, and behavior. They can be caused by genetics, infections, injuries, degeneration, or tumors. Examples of nervous system diseases include Alzheimer's disease, Parkinson's disease, multiple sclerosis, epilepsy, migraine, stroke, and neuroinfections like meningitis and encephalitis. The symptoms and severity of these disorders can vary widely, ranging from mild to severe and debilitating.

Echo-Planar Imaging (EPI) is a type of magnetic resonance imaging (MRI) technique that uses rapidly alternating magnetic field gradients and radiofrequency pulses to acquire multiple images in a very short period of time. This technique allows for the rapid acquisition of images, making it useful for functional MRI (fMRI) studies, diffusion-weighted imaging, and other applications where motion artifacts can be a problem.

In EPI, a single excitation pulse is followed by a series of gradient echoes that are acquired in a rapid succession, with each echo providing information about a different slice or plane of the object being imaged. The resulting images can then be combined to create a 3D representation of the object.

One of the key advantages of EPI is its speed, as it can acquire an entire brain volume in as little as 50 milliseconds. This makes it possible to capture rapid changes in the brain, such as those that occur during cognitive tasks or in response to neural activation. However, the technique can be susceptible to distortions and artifacts, particularly at higher field strengths, which can affect image quality and accuracy.

Intraoperative complications refer to any unforeseen problems or events that occur during the course of a surgical procedure, once it has begun and before it is completed. These complications can range from minor issues, such as bleeding or an adverse reaction to anesthesia, to major complications that can significantly impact the patient's health and prognosis.

Examples of intraoperative complications include:

1. Bleeding (hemorrhage) - This can occur due to various reasons such as injury to blood vessels or organs during surgery.
2. Infection - Surgical site infections can develop if the surgical area becomes contaminated during the procedure.
3. Anesthesia-related complications - These include adverse reactions to anesthesia, difficulty maintaining the patient's airway, or cardiovascular instability.
4. Organ injury - Accidental damage to surrounding organs can occur during surgery, leading to potential long-term consequences.
5. Equipment failure - Malfunctioning surgical equipment can lead to complications and compromise the safety of the procedure.
6. Allergic reactions - Patients may have allergies to certain medications or materials used during surgery, causing an adverse reaction.
7. Prolonged operative time - Complications may arise if a surgical procedure takes longer than expected, leading to increased risk of infection and other issues.

Intraoperative complications require prompt identification and management by the surgical team to minimize their impact on the patient's health and recovery.

Atrial septal defect (ASD) is a type of congenital heart defect that involves the septum, which is the wall that separates the two upper chambers of the heart (atria). An ASD is a hole or abnormal opening in the atrial septum, allowing oxygen-rich blood to leak into the oxygen-poor blood chambers in the heart. This leads to an overload of blood in the right side of the heart, which can cause enlargement of the heart and increased work for the right ventricle.

ASDs can vary in size, and small defects may not cause any symptoms or require treatment. Larger defects, however, can result in symptoms such as shortness of breath, fatigue, and heart rhythm abnormalities. Over time, if left untreated, ASDs can lead to complications like pulmonary hypertension, atrial fibrillation, and stroke.

Treatment for ASD typically involves surgical closure of the defect or catheter-based procedures using devices to close the hole. The choice of treatment depends on factors such as the size and location of the defect, the patient's age and overall health, and the presence of any coexisting conditions.

Prostheses: Artificial substitutes or replacements for missing body parts, such as limbs, eyes, or teeth. They are designed to restore the function, appearance, or mobility of the lost part. Prosthetic devices can be categorized into several types, including:

1. External prostheses: Devices that are attached to the outside of the body, like artificial arms, legs, hands, and feet. These may be further classified into:
a. Cosmetic or aesthetic prostheses: Primarily designed to improve the appearance of the affected area.
b. Functional prostheses: Designed to help restore the functionality and mobility of the lost limb.
2. Internal prostheses: Implanted artificial parts that replace missing internal organs, bones, or tissues, such as heart valves, hip joints, or intraocular lenses.

Implants: Medical devices or substances that are intentionally placed inside the body to replace or support a missing or damaged biological structure, deliver medication, monitor physiological functions, or enhance bodily functions. Examples of implants include:

1. Orthopedic implants: Devices used to replace or reinforce damaged bones, joints, or cartilage, such as knee or hip replacements.
2. Cardiovascular implants: Devices that help support or regulate heart function, like pacemakers, defibrillators, and artificial heart valves.
3. Dental implants: Artificial tooth roots that are placed into the jawbone to support dental prostheses, such as crowns, bridges, or dentures.
4. Neurological implants: Devices used to stimulate nerves, brain structures, or spinal cord tissues to treat various neurological conditions, like deep brain stimulators for Parkinson's disease or cochlear implants for hearing loss.
5. Ophthalmic implants: Artificial lenses that are placed inside the eye to replace a damaged or removed natural lens, such as intraocular lenses used in cataract surgery.

Prevalence, in medical terms, refers to the total number of people in a given population who have a particular disease or condition at a specific point in time, or over a specified period. It is typically expressed as a percentage or a ratio of the number of cases to the size of the population. Prevalence differs from incidence, which measures the number of new cases that develop during a certain period.

Cerebral arterial diseases refer to conditions that affect the blood vessels supplying the brain. These diseases can result in reduced blood flow, blockages, or bleeding in the brain. The most common cerebral arterial diseases include:

1. Atherosclerosis: A buildup of plaque made up of fat, cholesterol, and other substances in the inner lining of an artery, which can lead to narrowing or blockage of the artery.
2. Embolism: A blood clot or other particle that forms elsewhere in the body and travels to the brain, where it blocks a cerebral artery.
3. Thrombosis: The formation of a blood clot within a cerebral artery.
4. Aneurysm: A weakened area in the wall of an artery that bulges out and can rupture, causing bleeding in the brain.
5. Arteriovenous malformation (AVM): An abnormal tangle of blood vessels in the brain that can cause bleeding or reduced blood flow to surrounding tissue.
6. Vasculitis: Inflammation of the blood vessels in the brain, which can lead to narrowing, blockage, or weakening of the vessel walls.

These conditions can lead to serious complications such as stroke, transient ischemic attack (TIA), or vascular dementia. Treatment options include medications, surgery, and lifestyle changes to manage risk factors.

Clinical chemistry tests are a type of laboratory test that measure the levels of various chemicals or substances in the body. These tests can be used to help diagnose and monitor a wide range of medical conditions, including diabetes, liver disease, heart disease, and kidney disease. Some common clinical chemistry tests include:

1. Blood glucose test: Measures the level of glucose (sugar) in the blood. This test is commonly used to diagnose and monitor diabetes.
2. Electrolyte panel: Measures the levels of important electrolytes such as sodium, potassium, chloride, and bicarbonate in the blood. Imbalances in these electrolytes can indicate a variety of medical conditions.
3. Liver function tests (LFTs): Measure the levels of various enzymes and proteins produced by the liver. Abnormal results can indicate liver damage or disease.
4. Kidney function tests: Measure the levels of various substances such as creatinine and blood urea nitrogen (BUN) in the blood. Elevated levels of these substances can indicate kidney dysfunction or disease.
5. Lipid panel: Measures the levels of different types of cholesterol and triglycerides in the blood. Abnormal results can indicate an increased risk of heart disease.
6. Thyroid function tests: Measure the levels of hormones produced by the thyroid gland. Abnormal results can indicate thyroid dysfunction or disease.

Clinical chemistry tests are usually performed on a sample of blood, urine, or other bodily fluid. The results of these tests can provide important information to help doctors diagnose and manage medical conditions.

The Middle Cerebral Artery (MCA) is one of the main blood vessels that supplies oxygenated blood to the brain. It arises from the internal carotid artery and divides into several branches, which supply the lateral surface of the cerebral hemisphere, including the frontal, parietal, and temporal lobes.

The MCA is responsible for providing blood flow to critical areas of the brain, such as the primary motor and sensory cortices, Broca's area (associated with speech production), Wernicke's area (associated with language comprehension), and the visual association cortex.

Damage to the MCA or its branches can result in a variety of neurological deficits, depending on the specific location and extent of the injury. These may include weakness or paralysis on one side of the body, sensory loss, language impairment, and visual field cuts.

A carotid artery, internal, dissection is a medical condition that affects the internal carotid artery, which is a major blood vessel in the neck that supplies oxygenated blood to the brain. In this condition, there is a separation (dissection) of the layers of the artery wall, causing blood to accumulate in the space between the layers. This can lead to narrowing or blockage of the artery, reducing blood flow to the brain and increasing the risk of stroke. Internal carotid artery dissection can be caused by trauma, high blood pressure, connective tissue disorders, or spontaneously. Symptoms may include neck pain, headache, facial pain, visual disturbances, weakness or numbness in the arms or legs, difficulty speaking or understanding speech, and dizziness or loss of balance.

The common carotid artery is a major blood vessel in the neck that supplies oxygenated blood to the head and neck. It originates from the brachiocephalic trunk or the aortic arch and divides into the internal and external carotid arteries at the level of the upper border of the thyroid cartilage. The common carotid artery is an important structure in the circulatory system, and any damage or blockage to it can have serious consequences, including stroke.

Transient receptor potential (TRP) channels are a type of ion channel proteins that are widely expressed in various tissues and cells, including the sensory neurons, epithelial cells, and immune cells. They are named after the transient receptor potential mutant flies, which have defects in light-induced electrical responses due to mutations in TRP channels.

TRP channels are polymodal signal integrators that can be activated by a diverse range of physical and chemical stimuli, such as temperature, pressure, touch, osmolarity, pH, and various endogenous and exogenous ligands. Once activated, TRP channels allow the flow of cations, including calcium (Ca2+), sodium (Na+), and magnesium (Mg2+) ions, across the cell membrane.

TRP channels play critical roles in various physiological processes, such as sensory perception, neurotransmission, muscle contraction, cell proliferation, differentiation, migration, and apoptosis. Dysfunction of TRP channels has been implicated in a variety of pathological conditions, including pain, inflammation, neurodegenerative diseases, cardiovascular diseases, metabolic disorders, and cancer.

There are six subfamilies of TRP channels, based on their sequence homology and functional properties: TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPA (ankyrin), TRPP (polycystin), and TRPML (mucolipin). Each subfamily contains several members with distinct activation mechanisms, ion selectivity, and tissue distribution.

In summary, Transient Receptor Potential Channels are a group of polymodal cation channels that play critical roles in various physiological processes and are implicated in many pathological conditions.

I'm sorry for any confusion, but "United States" is a geopolitical entity, specifically the name of the country consisting of 50 states, and it is not a medical term or concept. Therefore, I can't provide a medical definition for it. If you have any questions related to health, medicine, or biology, I would be happy to try to help answer those!

Combination drug therapy is a treatment approach that involves the use of multiple medications with different mechanisms of action to achieve better therapeutic outcomes. This approach is often used in the management of complex medical conditions such as cancer, HIV/AIDS, and cardiovascular diseases. The goal of combination drug therapy is to improve efficacy, reduce the risk of drug resistance, decrease the likelihood of adverse effects, and enhance the overall quality of life for patients.

In combining drugs, healthcare providers aim to target various pathways involved in the disease process, which may help to:

1. Increase the effectiveness of treatment by attacking the disease from multiple angles.
2. Decrease the dosage of individual medications, reducing the risk and severity of side effects.
3. Slow down or prevent the development of drug resistance, a common problem in chronic diseases like HIV/AIDS and cancer.
4. Improve patient compliance by simplifying dosing schedules and reducing pill burden.

Examples of combination drug therapy include:

1. Antiretroviral therapy (ART) for HIV treatment, which typically involves three or more drugs from different classes to suppress viral replication and prevent the development of drug resistance.
2. Chemotherapy regimens for cancer treatment, where multiple cytotoxic agents are used to target various stages of the cell cycle and reduce the likelihood of tumor cells developing resistance.
3. Cardiovascular disease management, which may involve combining medications such as angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, diuretics, and statins to control blood pressure, heart rate, fluid balance, and cholesterol levels.
4. Treatment of tuberculosis, which often involves a combination of several antibiotics to target different aspects of the bacterial life cycle and prevent the development of drug-resistant strains.

When prescribing combination drug therapy, healthcare providers must carefully consider factors such as potential drug interactions, dosing schedules, adverse effects, and contraindications to ensure safe and effective treatment. Regular monitoring of patients is essential to assess treatment response, manage side effects, and adjust the treatment plan as needed.

Aphasia is a medical condition that affects a person's ability to communicate. It is caused by damage to the language areas of the brain, most commonly as a result of a stroke or head injury. Aphasia can affect both spoken and written language, making it difficult for individuals to express their thoughts, understand speech, read, or write.

There are several types of aphasia, including:

1. Expressive aphasia (also called Broca's aphasia): This type of aphasia affects a person's ability to speak and write clearly. Individuals with expressive aphasia know what they want to say but have difficulty forming the words or sentences to communicate their thoughts.
2. Receptive aphasia (also called Wernicke's aphasia): This type of aphasia affects a person's ability to understand spoken or written language. Individuals with receptive aphasia may struggle to follow conversations, comprehend written texts, or make sense of the words they hear or read.
3. Global aphasia: This is the most severe form of aphasia and results from extensive damage to the language areas of the brain. People with global aphasia have significant impairments in both their ability to express themselves and understand language.
4. Anomic aphasia: This type of aphasia affects a person's ability to recall the names of objects, people, or places. Individuals with anomic aphasia can speak in complete sentences but often struggle to find the right words to convey their thoughts.

Treatment for aphasia typically involves speech and language therapy, which aims to help individuals regain as much communication ability as possible. The success of treatment depends on various factors, such as the severity and location of the brain injury, the individual's motivation and effort, and the availability of support from family members and caregivers.

Hospital records are a type of medical record that is created and maintained by healthcare professionals during a patient's hospitalization. These records typically include detailed information about the patient's medical history, physical examination findings, laboratory and diagnostic test results, treatment plans, progress notes, medications, and other relevant data. The purpose of hospital records is to provide a comprehensive documentation of the patient's care while in the hospital, which can be used for clinical decision-making, communication among healthcare providers, quality improvement, research, and legal purposes. Hospital records are considered confidential and protected health information under federal and state laws, such as the Health Insurance Portability and Accountability Act (HIPAA).

Survival analysis is a branch of statistics that deals with the analysis of time to event data. It is used to estimate the time it takes for a certain event of interest to occur, such as death, disease recurrence, or treatment failure. The event of interest is called the "failure" event, and survival analysis estimates the probability of not experiencing the failure event until a certain point in time, also known as the "survival" probability.

Survival analysis can provide important information about the effectiveness of treatments, the prognosis of patients, and the identification of risk factors associated with the event of interest. It can handle censored data, which is common in medical research where some participants may drop out or be lost to follow-up before the event of interest occurs.

Survival analysis typically involves estimating the survival function, which describes the probability of surviving beyond a certain time point, as well as hazard functions, which describe the instantaneous rate of failure at a given time point. Other important concepts in survival analysis include median survival times, restricted mean survival times, and various statistical tests to compare survival curves between groups.

Logistic models, specifically logistic regression models, are a type of statistical analysis used in medical and epidemiological research to identify the relationship between the risk of a certain health outcome or disease (dependent variable) and one or more independent variables, such as demographic factors, exposure variables, or other clinical measurements.

In contrast to linear regression models, logistic regression models are used when the dependent variable is binary or dichotomous in nature, meaning it can only take on two values, such as "disease present" or "disease absent." The model uses a logistic function to estimate the probability of the outcome based on the independent variables.

Logistic regression models are useful for identifying risk factors and estimating the strength of associations between exposures and health outcomes, adjusting for potential confounders, and predicting the probability of an outcome given certain values of the independent variables. They can also be used to develop clinical prediction rules or scores that can aid in decision-making and patient care.

Cranial nerve injuries refer to damages or trauma to one or more of the twelve cranial nerves (CN I through CN XII). These nerves originate from the brainstem and are responsible for transmitting sensory information (such as vision, hearing, smell, taste, and balance) and controlling various motor functions (like eye movement, facial expressions, swallowing, and speaking).

Cranial nerve injuries can result from various causes, including head trauma, tumors, infections, or neurological conditions. The severity of the injury may range from mild dysfunction to complete loss of function, depending on the extent of damage to the nerve. Treatment options vary based on the type and location of the injury but often involve a combination of medical management, physical therapy, surgical intervention, or rehabilitation.

Neuroimaging is a medical term that refers to the use of various techniques to either directly or indirectly image the structure, function, or pharmacology of the nervous system. It includes techniques such as computed tomography (CT), magnetic resonance imaging (MRI), functional MRI (fMRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and diffusion tensor imaging (DTI). These techniques are used to diagnose and monitor various neurological and psychiatric conditions, as well as to understand the underlying mechanisms of brain function in health and disease.

Hospitalization is the process of admitting a patient to a hospital for the purpose of receiving medical treatment, surgery, or other health care services. It involves staying in the hospital as an inpatient, typically under the care of doctors, nurses, and other healthcare professionals. The length of stay can vary depending on the individual's medical condition and the type of treatment required. Hospitalization may be necessary for a variety of reasons, such as to receive intensive care, to undergo diagnostic tests or procedures, to recover from surgery, or to manage chronic illnesses or injuries.

Blood pressure is the force exerted by circulating blood on the walls of the blood vessels. It is measured in millimeters of mercury (mmHg) and is given as two figures:

1. Systolic pressure: This is the pressure when the heart pushes blood out into the arteries.
2. Diastolic pressure: This is the pressure when the heart rests between beats, allowing it to fill with blood.

Normal blood pressure for adults is typically around 120/80 mmHg, although this can vary slightly depending on age, sex, and other factors. High blood pressure (hypertension) is generally considered to be a reading of 130/80 mmHg or higher, while low blood pressure (hypotension) is usually defined as a reading below 90/60 mmHg. It's important to note that blood pressure can fluctuate throughout the day and may be affected by factors such as stress, physical activity, and medication use.

The basilar artery is a major blood vessel that supplies oxygenated blood to the brainstem and cerebellum. It is formed by the union of two vertebral arteries at the lower part of the brainstem, near the junction of the medulla oblongata and pons.

The basilar artery runs upward through the center of the brainstem and divides into two posterior cerebral arteries at the upper part of the brainstem, near the midbrain. The basilar artery gives off several branches that supply blood to various parts of the brainstem, including the pons, medulla oblongata, and midbrain, as well as to the cerebellum.

The basilar artery is an important part of the circle of Willis, a network of arteries at the base of the brain that ensures continuous blood flow to the brain even if one of the arteries becomes blocked or narrowed.

Diplopia is a medical term that refers to the condition where a person sees two images of a single object. It is commonly known as double vision. This can occur due to various reasons, such as nerve damage or misalignment of the eyes. Diplopia can be temporary or chronic and can affect one or both eyes. If you're experiencing diplopia, it's essential to consult an eye care professional for proper evaluation and treatment.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Thrombosis is the formation of a blood clot (thrombus) inside a blood vessel, obstructing the flow of blood through the circulatory system. When a clot forms in an artery, it can cut off the supply of oxygen and nutrients to the tissues served by that artery, leading to damage or tissue death. If a thrombus forms in the heart, it can cause a heart attack. If a thrombus breaks off and travels through the bloodstream, it can lodge in a smaller vessel, causing blockage and potentially leading to damage in the organ that the vessel supplies. This is known as an embolism.

Thrombosis can occur due to various factors such as injury to the blood vessel wall, abnormalities in blood flow, or changes in the composition of the blood. Certain medical conditions, medications, and lifestyle factors can increase the risk of thrombosis. Treatment typically involves anticoagulant or thrombolytic therapy to dissolve or prevent further growth of the clot, as well as addressing any underlying causes.

Platelet function tests are laboratory tests that measure how well platelets, which are small blood cells responsible for clotting, function in preventing or stopping bleeding. These tests are often used to investigate the cause of abnormal bleeding or bruising, or to monitor the effectiveness of antiplatelet therapy in patients with certain medical conditions such as heart disease or stroke.

There are several types of platelet function tests available, including:

1. Platelet count: This test measures the number of platelets present in a sample of blood. A low platelet count can increase the risk of bleeding.
2. Bleeding time: This test measures how long it takes for a small cut to stop bleeding. It is used less frequently than other tests due to its invasiveness and variability.
3. Platelet aggregation tests: These tests measure how well platelets clump together (aggregate) in response to various agents that promote platelet activation, such as adenosine diphosphate (ADP), collagen, or epinephrine.
4. Platelet function analyzer (PFA): This test measures the time it takes for a blood sample to clot under shear stress, simulating the conditions in an injured blood vessel. The PFA can provide information about the overall platelet function and the effectiveness of antiplatelet therapy.
5. Thromboelastography (TEG) or rotational thromboelastometry (ROTEM): These tests measure the kinetics of clot formation, strength, and dissolution in whole blood samples. They provide information about both platelet function and coagulation factors.

These tests can help healthcare providers diagnose bleeding disorders, assess the risk of bleeding during surgery or other invasive procedures, monitor antiplatelet therapy, and guide treatment decisions for patients with abnormal platelet function.

Clinical trials are research studies that involve human participants and are designed to evaluate the safety and efficacy of new medical treatments, drugs, devices, or behavioral interventions. The purpose of clinical trials is to determine whether a new intervention is safe, effective, and beneficial for patients, as well as to compare it with currently available treatments. Clinical trials follow a series of phases, each with specific goals and criteria, before a new intervention can be approved by regulatory authorities for widespread use.

Clinical trials are conducted according to a protocol, which is a detailed plan that outlines the study's objectives, design, methodology, statistical analysis, and ethical considerations. The protocol is developed and reviewed by a team of medical experts, statisticians, and ethicists, and it must be approved by an institutional review board (IRB) before the trial can begin.

Participation in clinical trials is voluntary, and participants must provide informed consent before enrolling in the study. Informed consent involves providing potential participants with detailed information about the study's purpose, procedures, risks, benefits, and alternatives, as well as their rights as research subjects. Participants can withdraw from the study at any time without penalty or loss of benefits to which they are entitled.

Clinical trials are essential for advancing medical knowledge and improving patient care. They help researchers identify new treatments, diagnostic tools, and prevention strategies that can benefit patients and improve public health. However, clinical trials also pose potential risks to participants, including adverse effects from experimental interventions, time commitment, and inconvenience. Therefore, it is important for researchers to carefully design and conduct clinical trials to minimize risks and ensure that the benefits outweigh the risks.

The double-blind method is a study design commonly used in research, including clinical trials, to minimize bias and ensure the objectivity of results. In this approach, both the participants and the researchers are unaware of which group the participants are assigned to, whether it be the experimental group or the control group. This means that neither the participants nor the researchers know who is receiving a particular treatment or placebo, thus reducing the potential for bias in the evaluation of outcomes. The assignment of participants to groups is typically done by a third party not involved in the study, and the codes are only revealed after all data have been collected and analyzed.

Disease progression is the worsening or advancement of a medical condition over time. It refers to the natural course of a disease, including its development, the severity of symptoms and complications, and the impact on the patient's overall health and quality of life. Understanding disease progression is important for developing appropriate treatment plans, monitoring response to therapy, and predicting outcomes.

The rate of disease progression can vary widely depending on the type of medical condition, individual patient factors, and the effectiveness of treatment. Some diseases may progress rapidly over a short period of time, while others may progress more slowly over many years. In some cases, disease progression may be slowed or even halted with appropriate medical interventions, while in other cases, the progression may be inevitable and irreversible.

In clinical practice, healthcare providers closely monitor disease progression through regular assessments, imaging studies, and laboratory tests. This information is used to guide treatment decisions and adjust care plans as needed to optimize patient outcomes and improve quality of life.

The Circle of Willis is a circulatory arrangement in the brain where the major arteries that supply blood to the brain converge to form an almost circular structure. It is named after Thomas Willis, an English physician who first described it in 1664.

This circle is formed by the joining of the two internal carotid arteries, which divide into the anterior cerebral and middle cerebral arteries, with the basilar artery, which arises from the vertebral arteries. These vessels anastomose, or connect, to form a polygon-like structure at the base of the brain.

The Circle of Willis plays a crucial role in maintaining adequate blood flow to the brain, as it allows for collateral circulation. If one of the arteries that make up the circle becomes blocked or narrowed, blood can still reach the affected area through the other vessels in the circle. This helps to minimize the risk of stroke and other neurological disorders.

Transient global amnesia (TGA) is a sudden, temporary episode of memory loss that cannot be explained by a more common neurological or medical condition. It is characterized by an inability to form new memories (anterograde amnesia) and to recall past events or personal information (retrograde amnesia). These memory gaps typically last for several hours, but may persist for up to 24 hours.

TGA usually affects people over the age of 50 and is more common in men than women. The exact cause of TGA is not known, although it has been associated with various triggers such as emotional stress, physical exertion, sudden immersion in cold water, sexual activity, and medical procedures.

During a TGA episode, individuals often repeat the same questions or statements due to their inability to form new memories. They may also appear confused or disoriented, but they typically remain conscious and maintain their ability to perform familiar tasks. Most people with TGA do not experience any long-term memory loss or other neurological symptoms after the episode resolves.

The diagnosis of TGA is based on the characteristic symptoms, a normal physical examination, and the exclusion of other potential causes of amnesia through medical testing. Treatment for TGA is generally supportive, focusing on reassuring the individual and providing a safe environment during the episode. Recurrent episodes of TGA are uncommon but can occur in some individuals.

Reproducibility of results in a medical context refers to the ability to obtain consistent and comparable findings when a particular experiment or study is repeated, either by the same researcher or by different researchers, following the same experimental protocol. It is an essential principle in scientific research that helps to ensure the validity and reliability of research findings.

In medical research, reproducibility of results is crucial for establishing the effectiveness and safety of new treatments, interventions, or diagnostic tools. It involves conducting well-designed studies with adequate sample sizes, appropriate statistical analyses, and transparent reporting of methods and findings to allow other researchers to replicate the study and confirm or refute the results.

The lack of reproducibility in medical research has become a significant concern in recent years, as several high-profile studies have failed to produce consistent findings when replicated by other researchers. This has led to increased scrutiny of research practices and a call for greater transparency, rigor, and standardization in the conduct and reporting of medical research.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Antihypertensive agents are a class of medications used to treat high blood pressure (hypertension). They work by reducing the force and rate of heart contractions, dilating blood vessels, or altering neurohormonal activation to lower blood pressure. Examples include diuretics, beta blockers, ACE inhibitors, ARBs, calcium channel blockers, and direct vasodilators. These medications may be used alone or in combination to achieve optimal blood pressure control.

A subarachnoid hemorrhage is a type of stroke that results from bleeding into the space surrounding the brain, specifically within the subarachnoid space which contains cerebrospinal fluid (CSF). This space is located between the arachnoid membrane and the pia mater, two of the three layers that make up the meninges, the protective covering of the brain and spinal cord.

The bleeding typically originates from a ruptured aneurysm, a weakened area in the wall of a cerebral artery, or less commonly from arteriovenous malformations (AVMs) or head trauma. The sudden influx of blood into the CSF-filled space can cause increased intracranial pressure, irritation to the brain, and vasospasms, leading to further ischemia and potential additional neurological damage.

Symptoms of a subarachnoid hemorrhage may include sudden onset of severe headache (often described as "the worst headache of my life"), neck stiffness, altered mental status, nausea, vomiting, photophobia, and focal neurological deficits. Rapid diagnosis and treatment are crucial to prevent further complications and improve the chances of recovery.

Ischemic preconditioning is a phenomenon in which brief, non-lethal episodes of ischemia (restriction or interruption of blood supply to an organ or tissue) render the tissue more resistant to subsequent prolonged ischemia and reperfusion injury. This adaptive response involves a complex series of cellular and molecular changes that protect the myocardium, brain, kidney, or other organs from ischemic damage. The underlying mechanisms include the activation of various signaling pathways, such as adenosine, opioid, and kinase pathways, which lead to the production of protective factors and the modulation of cellular responses to ischemia and reperfusion injury. Ischemic preconditioning has been extensively studied in the context of cardiovascular medicine, where it has been shown to reduce infarct size and improve cardiac function after myocardial infarction. However, this protective phenomenon has also been observed in other organs and systems, including the brain, kidney, liver, and skeletal muscle.

An intracranial aneurysm is a localized, blood-filled dilation or bulging in the wall of a cerebral artery within the skull (intracranial). These aneurysms typically occur at weak points in the arterial walls, often at branching points where the vessel divides into smaller branches. Over time, the repeated pressure from blood flow can cause the vessel wall to weaken and balloon out, forming a sac-like structure. Intracranial aneurysms can vary in size, ranging from a few millimeters to several centimeters in diameter.

There are three main types of intracranial aneurysms:

1. Saccular (berry) aneurysm: This is the most common type, characterized by a round or oval shape with a narrow neck and a bulging sac. They usually develop at branching points in the arteries due to congenital weaknesses in the vessel wall.
2. Fusiform aneurysm: These aneurysms have a dilated segment along the length of the artery, forming a cigar-shaped or spindle-like structure. They are often caused by atherosclerosis and can affect any part of the cerebral arteries.
3. Dissecting aneurysm: This type occurs when there is a tear in the inner lining (intima) of the artery, allowing blood to flow between the layers of the vessel wall. It can lead to narrowing or complete blockage of the affected artery and may cause subarachnoid hemorrhage if it ruptures.

Intracranial aneurysms can be asymptomatic and discovered incidentally during imaging studies for other conditions. However, when they grow larger or rupture, they can lead to severe complications such as subarachnoid hemorrhage, stroke, or even death. Treatment options include surgical clipping, endovascular coiling, or flow diversion techniques to prevent further growth and potential rupture of the aneurysm.

Calcium signaling is the process by which cells regulate various functions through changes in intracellular calcium ion concentrations. Calcium ions (Ca^2+^) are crucial second messengers that play a critical role in many cellular processes, including muscle contraction, neurotransmitter release, gene expression, and programmed cell death (apoptosis).

Intracellular calcium levels are tightly regulated by a complex network of channels, pumps, and exchangers located on the plasma membrane and intracellular organelles such as the endoplasmic reticulum (ER) and mitochondria. These proteins control the influx, efflux, and storage of calcium ions within the cell.

Calcium signaling is initiated when an external signal, such as a hormone or neurotransmitter, binds to a specific receptor on the plasma membrane. This interaction triggers the opening of ion channels, allowing extracellular Ca^2+^ to flow into the cytoplasm. In some cases, this influx of calcium ions is sufficient to activate downstream targets directly. However, in most instances, the increase in intracellular Ca^2+^ serves as a trigger for the release of additional calcium from internal stores, such as the ER.

The release of calcium from the ER is mediated by ryanodine receptors (RyRs) and inositol trisphosphate receptors (IP3Rs), which are activated by specific second messengers generated in response to the initial external signal. The activation of these channels leads to a rapid increase in cytoplasmic Ca^2+^, creating a transient intracellular calcium signal known as a "calcium spark" or "calcium puff."

These localized increases in calcium concentration can then propagate throughout the cell as waves of elevated calcium, allowing for the spatial and temporal coordination of various cellular responses. The duration and amplitude of these calcium signals are finely tuned by the interplay between calcium-binding proteins, pumps, and exchangers, ensuring that appropriate responses are elicited in a controlled manner.

Dysregulation of intracellular calcium signaling has been implicated in numerous pathological conditions, including neurodegenerative diseases, cardiovascular disorders, and cancer. Therefore, understanding the molecular mechanisms governing calcium homeostasis and signaling is crucial for the development of novel therapeutic strategies targeting these diseases.

Sensitivity and specificity are statistical measures used to describe the performance of a diagnostic test or screening tool in identifying true positive and true negative results.

* Sensitivity refers to the proportion of people who have a particular condition (true positives) who are correctly identified by the test. It is also known as the "true positive rate" or "recall." A highly sensitive test will identify most or all of the people with the condition, but may also produce more false positives.
* Specificity refers to the proportion of people who do not have a particular condition (true negatives) who are correctly identified by the test. It is also known as the "true negative rate." A highly specific test will identify most or all of the people without the condition, but may also produce more false negatives.

In medical testing, both sensitivity and specificity are important considerations when evaluating a diagnostic test. High sensitivity is desirable for screening tests that aim to identify as many cases of a condition as possible, while high specificity is desirable for confirmatory tests that aim to rule out the condition in people who do not have it.

It's worth noting that sensitivity and specificity are often influenced by factors such as the prevalence of the condition in the population being tested, the threshold used to define a positive result, and the reliability and validity of the test itself. Therefore, it's important to consider these factors when interpreting the results of a diagnostic test.

Blood flow velocity is the speed at which blood travels through a specific part of the vascular system. It is typically measured in units of distance per time, such as centimeters per second (cm/s) or meters per second (m/s). Blood flow velocity can be affected by various factors, including cardiac output, vessel diameter, and viscosity of the blood. Measuring blood flow velocity is important in diagnosing and monitoring various medical conditions, such as heart disease, stroke, and peripheral vascular disease.

An emergency service in a hospital is a department that provides immediate medical or surgical care for individuals who are experiencing an acute illness, injury, or severe symptoms that require immediate attention. The goal of an emergency service is to quickly assess, stabilize, and treat patients who require urgent medical intervention, with the aim of preventing further harm or death.

Emergency services in hospitals typically operate 24 hours a day, 7 days a week, and are staffed by teams of healthcare professionals including physicians, nurses, physician assistants, nurse practitioners, and other allied health professionals. These teams are trained to provide rapid evaluation and treatment for a wide range of medical conditions, from minor injuries to life-threatening emergencies such as heart attacks, strokes, and severe infections.

In addition to providing emergency care, hospital emergency services also serve as a key point of entry for patients who require further hospitalization or specialized care. They work closely with other departments within the hospital, such as radiology, laboratory, and critical care units, to ensure that patients receive timely and appropriate treatment. Overall, the emergency service in a hospital plays a crucial role in ensuring that patients receive prompt and effective medical care during times of crisis.

Diabetes Mellitus is a chronic metabolic disorder characterized by elevated levels of glucose in the blood (hyperglycemia) due to absolute or relative deficiency in insulin secretion and/or insulin action. There are two main types: Type 1 diabetes, which results from the autoimmune destruction of pancreatic beta cells leading to insulin deficiency, and Type 2 diabetes, which is associated with insulin resistance and relative insulin deficiency.

Type 1 diabetes typically presents in childhood or young adulthood, while Type 2 diabetes tends to occur later in life, often in association with obesity and physical inactivity. Both types of diabetes can lead to long-term complications such as damage to the eyes, kidneys, nerves, and cardiovascular system if left untreated or not well controlled.

The diagnosis of diabetes is usually made based on fasting plasma glucose levels, oral glucose tolerance tests, or hemoglobin A1c (HbA1c) levels. Treatment typically involves lifestyle modifications such as diet and exercise, along with medications to lower blood glucose levels and manage associated conditions.

Digital subtraction angiography (DSA) is a medical imaging technique used to visualize the blood vessels and blood flow within the body. It combines the use of X-ray technology with digital image processing to produce detailed images of the vascular system.

In DSA, a contrast agent is injected into the patient's bloodstream through a catheter, which is typically inserted into an artery in the leg and guided to the area of interest using fluoroscopy. As the contrast agent flows through the blood vessels, X-ray images are taken at multiple time points.

The digital subtraction process involves taking a baseline image without contrast and then subtracting it from subsequent images taken with contrast. This allows for the removal of background structures and noise, resulting in clearer images of the blood vessels. DSA can be used to diagnose and evaluate various vascular conditions, such as aneurysms, stenosis, and tumors, and can also guide interventional procedures such as angioplasty and stenting.

Cardiovascular diseases (CVDs) are a class of diseases that affect the heart and blood vessels. They are the leading cause of death globally, according to the World Health Organization (WHO). The term "cardiovascular disease" refers to a group of conditions that include:

1. Coronary artery disease (CAD): This is the most common type of heart disease and occurs when the arteries that supply blood to the heart become narrowed or blocked due to the buildup of cholesterol, fat, and other substances in the walls of the arteries. This can lead to chest pain, shortness of breath, or a heart attack.
2. Heart failure: This occurs when the heart is unable to pump blood efficiently to meet the body's needs. It can be caused by various conditions, including coronary artery disease, high blood pressure, and cardiomyopathy.
3. Stroke: A stroke occurs when the blood supply to a part of the brain is interrupted or reduced, often due to a clot or a ruptured blood vessel. This can cause brain damage or death.
4. Peripheral artery disease (PAD): This occurs when the arteries that supply blood to the limbs become narrowed or blocked, leading to pain, numbness, or weakness in the legs or arms.
5. Rheumatic heart disease: This is a complication of untreated strep throat and can cause damage to the heart valves, leading to heart failure or other complications.
6. Congenital heart defects: These are structural problems with the heart that are present at birth. They can range from mild to severe and may require medical intervention.
7. Cardiomyopathy: This is a disease of the heart muscle that makes it harder for the heart to pump blood efficiently. It can be caused by various factors, including genetics, infections, and certain medications.
8. Heart arrhythmias: These are abnormal heart rhythms that can cause the heart to beat too fast, too slow, or irregularly. They can lead to symptoms such as palpitations, dizziness, or fainting.
9. Valvular heart disease: This occurs when one or more of the heart valves become damaged or diseased, leading to problems with blood flow through the heart.
10. Aortic aneurysm and dissection: These are conditions that affect the aorta, the largest artery in the body. An aneurysm is a bulge in the aorta, while a dissection is a tear in the inner layer of the aorta. Both can be life-threatening if not treated promptly.

It's important to note that many of these conditions can be managed or treated with medical interventions such as medications, surgery, or lifestyle changes. If you have any concerns about your heart health, it's important to speak with a healthcare provider.

Human platelet antigens (HPAs) are a group of cell surface proteins found on platelets and megakaryocytes, which are the precursor cells that produce platelets. These antigens can stimulate an immune response when they are recognized as foreign by the body's immune system, leading to the production of antibodies against them.

HPAs are classified into several different systems based on their genetic inheritance and immunological properties. The most well-known HPA systems are HPA-1, HPA-2, HPA-3, HPA-4, and HPA-5. Each system consists of a pair of alleles, one inherited from each parent, that code for different variants of the antigen.

HPAs can play a role in the development of certain bleeding disorders, such as neonatal alloimmune thrombocytopenia (NAIT) and post-transfusion purpura (PTP). NAIT occurs when a pregnant woman develops antibodies against her fetus's HPAs, leading to low platelet counts and bleeding in the newborn. PTP can occur after a transfusion of blood products containing HPAs that are not compatible with the recipient's HPAs, leading to an immune response and destruction of the transfused platelets.

It is important for healthcare providers to consider HPA compatibility when performing platelet transfusions or managing pregnant women at risk of developing antibodies against HPAs.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Middle Cerebral Artery (MCA) infarction is a type of ischemic stroke that occurs when there is an obstruction in the blood supply to the middle cerebral artery, which is one of the major blood vessels that supplies oxygenated blood to the brain. The MCA supplies blood to a large portion of the brain, including the motor and sensory cortex, parts of the temporal and parietal lobes, and the basal ganglia.

An infarction is the death of tissue due to the lack of blood supply, which can lead to damage or loss of function in the affected areas of the brain. Symptoms of MCA infarction may include weakness or numbness on one side of the body, difficulty speaking or understanding speech, vision problems, and altered levels of consciousness.

MCA infarctions can be caused by various factors, including embolism (a blood clot that travels to the brain from another part of the body), thrombosis (a blood clot that forms in the MCA itself), or stenosis (narrowing of the artery due to atherosclerosis or other conditions). Treatment for MCA infarction may include medications to dissolve blood clots, surgery to remove the obstruction, or rehabilitation to help regain lost function.

Hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors, also known as statins, are a class of cholesterol-lowering medications. They work by inhibiting the enzyme HMG-CoA reductase, which plays a central role in the production of cholesterol in the liver. By blocking this enzyme, the liver is stimulated to take up more low-density lipoprotein (LDL) cholesterol from the bloodstream, leading to a decrease in LDL cholesterol levels and a reduced risk of cardiovascular disease.

Examples of HMG-CoA reductase inhibitors include atorvastatin, simvastatin, pravastatin, rosuvastatin, and fluvastatin. These medications are commonly prescribed to individuals with high cholesterol levels, particularly those who are at risk for or have established cardiovascular disease.

It's important to note that while HMG-CoA reductase inhibitors can be effective in reducing LDL cholesterol levels and the risk of cardiovascular events, they should be used as part of a comprehensive approach to managing high cholesterol, which may also include lifestyle modifications such as dietary changes, exercise, and weight management.

Smoking is not a medical condition, but it's a significant health risk behavior. Here is the definition from a public health perspective:

Smoking is the act of inhaling and exhaling the smoke of burning tobacco that is commonly consumed through cigarettes, pipes, and cigars. The smoke contains over 7,000 chemicals, including nicotine, tar, carbon monoxide, and numerous toxic and carcinogenic substances. These toxins contribute to a wide range of diseases and health conditions, such as lung cancer, heart disease, stroke, chronic obstructive pulmonary disease (COPD), and various other cancers, as well as adverse reproductive outcomes and negative impacts on the developing fetus during pregnancy. Smoking is highly addictive due to the nicotine content, which makes quitting smoking a significant challenge for many individuals.

A feasibility study is a preliminary investigation or analysis conducted to determine the viability of a proposed project, program, or product. In the medical field, feasibility studies are often conducted before implementing new treatments, procedures, equipment, or facilities. These studies help to assess the practicality and effectiveness of the proposed intervention, as well as its potential benefits and risks.

Feasibility studies in healthcare typically involve several steps:

1. Problem identification: Clearly define the problem that the proposed project, program, or product aims to address.
2. Objectives setting: Establish specific, measurable, achievable, relevant, and time-bound (SMART) objectives for the study.
3. Literature review: Conduct a thorough review of existing research and best practices related to the proposed intervention.
4. Methodology development: Design a methodology for data collection and analysis that will help answer the research questions and achieve the study's objectives.
5. Resource assessment: Evaluate the availability and adequacy of resources, including personnel, time, and finances, required to carry out the proposed intervention.
6. Risk assessment: Identify potential risks and challenges associated with the implementation of the proposed intervention and develop strategies to mitigate them.
7. Cost-benefit analysis: Estimate the costs and benefits of the proposed intervention, including direct and indirect costs, as well as short-term and long-term benefits.
8. Stakeholder engagement: Engage relevant stakeholders, such as patients, healthcare providers, administrators, and policymakers, to gather their input and support for the proposed intervention.
9. Decision-making: Based on the findings of the feasibility study, make an informed decision about whether or not to proceed with the proposed project, program, or product.

Feasibility studies are essential in healthcare as they help ensure that resources are allocated efficiently and effectively, and that interventions are evidence-based, safe, and beneficial for patients.

Atherosclerosis is a medical condition characterized by the buildup of plaques, made up of fat, cholesterol, calcium, and other substances found in the blood, on the inner walls of the arteries. This process gradually narrows and hardens the arteries, reducing the flow of oxygen-rich blood to various parts of the body. Atherosclerosis can affect any artery in the body, including those that supply blood to the heart (coronary arteries), brain, limbs, and other organs. The progressive narrowing and hardening of the arteries can lead to serious complications such as coronary artery disease, carotid artery disease, peripheral artery disease, and aneurysms, which can result in heart attacks, strokes, or even death if left untreated.

The exact cause of atherosclerosis is not fully understood, but it is believed to be associated with several risk factors, including high blood pressure, high cholesterol levels, smoking, diabetes, obesity, physical inactivity, and a family history of the condition. Atherosclerosis can often progress without any symptoms for many years, but as the disease advances, it can lead to various signs and symptoms depending on which arteries are affected. Treatment typically involves lifestyle changes, medications, and, in some cases, surgical procedures to restore blood flow.

Regression analysis is a statistical technique used in medicine, as well as in other fields, to examine the relationship between one or more independent variables (predictors) and a dependent variable (outcome). It allows for the estimation of the average change in the outcome variable associated with a one-unit change in an independent variable, while controlling for the effects of other independent variables. This technique is often used to identify risk factors for diseases or to evaluate the effectiveness of medical interventions. In medical research, regression analysis can be used to adjust for potential confounding variables and to quantify the relationship between exposures and health outcomes. It can also be used in predictive modeling to estimate the probability of a particular outcome based on multiple predictors.

In medical terms, the "neck" is defined as the portion of the body that extends from the skull/head to the thorax or chest region. It contains 7 cervical vertebrae, muscles, nerves, blood vessels, lymphatic vessels, and glands (such as the thyroid gland). The neck is responsible for supporting the head, allowing its movement in various directions, and housing vital structures that enable functions like respiration and circulation.

Life tables are statistical tools used in actuarial science, demography, and public health to estimate the mortality rate and survival rates of a population. They provide a data-driven representation of the probability that individuals of a certain age will die before their next birthday (the death rate) or live to a particular age (the survival rate).

Life tables are constructed using data on the number of deaths and the size of the population in specific age groups over a given period. These tables typically include several columns representing different variables, such as:

1. Age group or interval: The age range for which the data is being presented (e.g., 0-1 year, 1-5 years, 5-10 years, etc.).
2. Number of people in the population: The size of the population within each age group.
3. Number of deaths: The number of individuals who died during the study period within each age group.
4. Death rate: The probability that an individual in a given age group will die before their next birthday. It is calculated as the number of deaths divided by the size of the population for that age group.
5. Survival rate: The probability that an individual in a given age group will survive to a specific age or older. It is calculated using the death rates from earlier age groups.
6. Life expectancy: The average number of years a person is expected to live, based on their current age and mortality rates for each subsequent age group.

Life tables are essential in various fields, including insurance, pension planning, social security administration, and healthcare policy development. They help researchers and policymakers understand the health status and demographic trends of populations, allowing them to make informed decisions about resource allocation, program development, and public health interventions.

A factual database in the medical context is a collection of organized and structured data that contains verified and accurate information related to medicine, healthcare, or health sciences. These databases serve as reliable resources for various stakeholders, including healthcare professionals, researchers, students, and patients, to access evidence-based information for making informed decisions and enhancing knowledge.

Examples of factual medical databases include:

1. PubMed: A comprehensive database of biomedical literature maintained by the US National Library of Medicine (NLM). It contains citations and abstracts from life sciences journals, books, and conference proceedings.
2. MEDLINE: A subset of PubMed, MEDLINE focuses on high-quality, peer-reviewed articles related to biomedicine and health. It is the primary component of the NLM's database and serves as a critical resource for healthcare professionals and researchers worldwide.
3. Cochrane Library: A collection of systematic reviews and meta-analyses focused on evidence-based medicine. The library aims to provide unbiased, high-quality information to support clinical decision-making and improve patient outcomes.
4. OVID: A platform that offers access to various medical and healthcare databases, including MEDLINE, Embase, and PsycINFO. It facilitates the search and retrieval of relevant literature for researchers, clinicians, and students.
5. ClinicalTrials.gov: A registry and results database of publicly and privately supported clinical studies conducted around the world. The platform aims to increase transparency and accessibility of clinical trial data for healthcare professionals, researchers, and patients.
6. UpToDate: An evidence-based, physician-authored clinical decision support resource that provides information on diagnosis, treatment, and prevention of medical conditions. It serves as a point-of-care tool for healthcare professionals to make informed decisions and improve patient care.
7. TRIP Database: A search engine designed to facilitate evidence-based medicine by providing quick access to high-quality resources, including systematic reviews, clinical guidelines, and practice recommendations.
8. National Guideline Clearinghouse (NGC): A database of evidence-based clinical practice guidelines and related documents developed through a rigorous review process. The NGC aims to provide clinicians, healthcare providers, and policymakers with reliable guidance for patient care.
9. DrugBank: A comprehensive, freely accessible online database containing detailed information about drugs, their mechanisms, interactions, and targets. It serves as a valuable resource for researchers, healthcare professionals, and students in the field of pharmacology and drug discovery.
10. Genetic Testing Registry (GTR): A database that provides centralized information about genetic tests, test developers, laboratories offering tests, and clinical validity and utility of genetic tests. It serves as a resource for healthcare professionals, researchers, and patients to make informed decisions regarding genetic testing.

A multicenter study is a type of clinical research study that involves multiple centers or institutions. These studies are often conducted to increase the sample size and diversity of the study population, which can improve the generalizability of the study results. In a multicenter study, data is collected from participants at multiple sites and then analyzed together to identify patterns, trends, and relationships in the data. This type of study design can be particularly useful for researching rare diseases or conditions, or for testing new treatments or interventions that require a large number of participants.

Multicenter studies can be either interventional (where participants are randomly assigned to receive different treatments or interventions) or observational (where researchers collect data on participants' characteristics and outcomes without intervening). In both cases, it is important to ensure standardization of data collection and analysis procedures across all study sites to minimize bias and ensure the validity and reliability of the results.

Multicenter studies can provide valuable insights into the effectiveness and safety of new treatments or interventions, as well as contribute to our understanding of disease mechanisms and risk factors. However, they can also be complex and expensive to conduct, requiring careful planning, coordination, and management to ensure their success.

Panic Disorder is a type of anxiety disorder characterized by recurrent, unexpected panic attacks and significant worry about the implications of these attacks or fear of their occurrence. A panic attack is a sudden surge of intense fear or discomfort that reaches a peak within minutes, and includes physical symptoms such as accelerated heart rate, sweating, trembling, shortness of breath, and feelings of impending doom or danger. In Panic Disorder, these attacks are not triggered by specific situations or stimuli, but can occur spontaneously and without warning. The individual may also develop avoidance behaviors to prevent future panic attacks, which can interfere with daily functioning and quality of life.

Thrombophilia is a medical condition characterized by an increased tendency to form blood clots (thrombi) due to various genetic or acquired abnormalities in the coagulation system. These abnormalities can lead to a hypercoagulable state, which can cause thrombosis in both veins and arteries. Commonly identified thrombophilias include factor V Leiden mutation, prothrombin G20210A mutation, antithrombin deficiency, protein C deficiency, and protein S deficiency.

Acquired thrombophilias can be caused by various factors such as antiphospholipid antibody syndrome (APS), malignancies, pregnancy, oral contraceptive use, hormone replacement therapy, and certain medical conditions like inflammatory bowel disease or nephrotic syndrome.

It is essential to diagnose thrombophilia accurately, as it may influence the management of venous thromboembolism (VTE) events and guide decisions regarding prophylactic anticoagulation in high-risk situations.

A septal occluder device is a type of medical implant used to close defects or holes in the heart, specifically within the septum, which is the wall that separates the two sides of the heart. The device typically consists of two disc-shaped components connected by a waist, resembling a button or an umbrella.

The procedure for implanting a septal occluder device involves inserting it through a catheter, which is introduced into a vein in the leg and guided to the heart. Once in position, the discs of the device expand and are pressed against the septum on both sides of the hole, effectively closing it. Over time, tissue grows over the device, permanently sealing the defect.

Septal occluder devices are commonly used to treat atrial septal defects (ASD) and patent foramen ovale (PFO), which are two types of congenital heart defects that can cause symptoms such as shortness of breath, fatigue, and heart palpitations. The use of these devices has revolutionized the treatment of these conditions, allowing for less invasive procedures and faster recovery times compared to traditional surgical methods.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

"Endpoint determination" is a medical term that refers to the process of deciding when a clinical trial or study should be stopped or concluded based on the outcomes or results that have been observed. The endpoint of a study is the primary outcome or result that the study is designed to investigate and measure.

In endpoint determination, researchers use pre-specified criteria, such as statistical significance levels or safety concerns, to evaluate whether the study has met its objectives or if there are any significant benefits or risks associated with the intervention being studied. The decision to end a study early can be based on various factors, including the achievement of a predefined level of efficacy, the emergence of unexpected safety issues, or the realization that the study is unlikely to achieve its intended goals.

Endpoint determination is an important aspect of clinical trial design and conduct, as it helps ensure that studies are conducted in an ethical and scientifically rigorous manner, and that their results can be used to inform medical practice and policy.

In medical terms, "outpatients" refers to individuals who receive medical care or treatment at a hospital or clinic without being admitted as inpatients. This means that they do not stay overnight or for an extended period; instead, they visit the healthcare facility for specific services such as consultations, diagnostic tests, treatments, or follow-up appointments and then return home afterward. Outpatient care can include various services like primary care, specialty clinics, dental care, physical therapy, and more. It is often more convenient and cost-effective than inpatient care, as it allows patients to maintain their daily routines while receiving necessary medical attention.

Cardiac catheterization is a medical procedure used to diagnose and treat cardiovascular conditions. In this procedure, a thin, flexible tube called a catheter is inserted into a blood vessel in the arm or leg and threaded up to the heart. The catheter can be used to perform various diagnostic tests, such as measuring the pressure inside the heart chambers and assessing the function of the heart valves.

Cardiac catheterization can also be used to treat certain cardiovascular conditions, such as narrowed or blocked arteries. In these cases, a balloon or stent may be inserted through the catheter to open up the blood vessel and improve blood flow. This procedure is known as angioplasty or percutaneous coronary intervention (PCI).

Cardiac catheterization is typically performed in a hospital cardiac catheterization laboratory by a team of healthcare professionals, including cardiologists, radiologists, and nurses. The procedure may be done under local anesthesia with sedation or general anesthesia, depending on the individual patient's needs and preferences.

Overall, cardiac catheterization is a valuable tool in the diagnosis and treatment of various heart conditions, and it can help improve symptoms, reduce complications, and prolong life for many patients.

A transient ischemic attack (TIA), commonly known as a mini-stroke, is a minor stroke whose noticeable symptoms usually end in ... Presence of ischemic lesions on diffusion weighted imaging has been correlated with a higher risk of stroke after a TIA. ... TIAs used to be defined as ischemic events in the brain that last less than 24 hours, but given the variation in duration of ... Sometimes, myocardial infarction ("heart attack") may lead to the formation of a blood clot in one of the chambers of the heart ...
"Transient Ischemic Attack". medlineplus.gov. Retrieved 2021-10-27. "What is a TIA". www.stroke.org. Retrieved 2021-10-27. " ... A sudden, brief episode (symptoms lasting only minutes) of ischemia affecting the brain is called a transient ischemic attack ( ... Acute ischemic stroke is a neurological emergency typically caused by a blood clot blocking blood flow in a vessel in the brain ... Ischemic stroke is at times treated with various levels of statin therapy at hospital discharge, followed by home time, in an ...
Stroke and transient ischemic attacks. Intercranial aneurysm, arterial-venous malformation or tumor. Exertional angina, ... may be exposed to environmental factors that increase the risk of bronchospasm and the development of an acute asthmatic attack ...
Transient ischemic attack "Apoplexy". MedicineNet.com. Retrieved 2022-05-09. apoplexy. 2012. Retrieved 2022-05-09 - via ... and even heart attacks and strokes were referred to as apoplexy in the past, because before the advent of medical science, ...
Vertebrobasilar transient ischemic attacks may produce true syncope as a symptom. The respiratory system may compensate for ... Common examples include strokes and transient ischemic attacks. While these conditions often impair consciousness they rarely ... This may avert a complete collapse, but whether the patient sits down or falls down, the result of an ischaemic episode is a ... However, the resulting "transient orthostatic hypotension" does not necessarily signal any serious underlying disease. It is as ...
A transient ischemic attack is a "mini-stroke". TIA or Tia may also refer to: Tia (moth), a genus of moths in the family ...
Cerebrovascular disease, stroke and transient ischemic attack (TIA). Peripheral arterial disease, intermittent claudication and ... transient ischemic attack (TIA), and heart failure. These also important patient outcomes were included in the 2008 Framingham ...
October 2014). "Effect of high-dose atorvastatin on renal function in subjects with stroke or transient ischemic attack in the ... August 2006). "High-dose atorvastatin after stroke or transient ischemic attack". The New England Journal of Medicine. 355 (6 ... such as heart attack or ischaemic stroke) or in people at high risk of cardiovascular disease. People taking atorvastatin ... Law MR, Wald NJ, Rudnicka AR (June 2003). "Quantifying effect of statins on low density lipoprotein cholesterol, ischaemic ...
In June 2019, McIngvale suffered a possible transient ischemic attack. During the 2022 World Series, McIngvale attended Game 3 ... which attacked Lina Hidalgo, a Democrat running for County judge of Harris County. After Hidalgo won re-election, McIngvale ...
This may lead to a stroke or transient ischemic attack. Transesophageal echocardiography is considered the most accurate ...
"Silent stroke in patients with transient ischemic attack or minor ischemic stroke. The Dutch TIA Trial Study Group". Stroke: A ... A silent stroke differs from a transient ischemic attack (TIA). In TIA symptoms of stroke are exhibited which may last from a ... a silent stroke still causes damage to the brain and places the patient at increased risk for both transient ischemic attack ... Ischemic stroke: occurs when a blood vessel supplying blood to the brain becomes blocked. This type of stroke accounts for ...
This leads to ischemic problems including transient ischemic attack and stroke.[citation needed] Leukocytosis is very common in ...
"National Stroke Association guidelines for the management of transient ischemic attacks". Ann Neurol. US National Library of ... the Annals of Neurology published National Stroke Association's guidelines for the management of transient ischemic attacks. ...
"Diagnosis and Management of Transient Ischemic Attack and Acute Ischemic Stroke". JAMA. 325 (11): 1088-1098. doi:10.1001/jama. ... Nevertheless, non-ischemic venous thrombosis may still be problematic, due to the swelling caused by blockage to venous ... A venous thrombus may or may not be ischemic, since veins distribute deoxygenated blood that is less vital for cellular ... Ho, Andrew Fu Wah; Jun, Chong; Ong, Marcus Eng Hock; Hausenloy, Derek J. (April 2019). "Remote Ischemic Conditioning in ...
For maximum benefit people should be operated on soon after a stroke or transient ischemic attack, preferably within the first ... Symptomatic people have had either a stroke or transient ischemic attack. In symptomatic patients with a 70-99% stenosis, for ... Asymptomatic people have narrowing of their carotid arteries, but have not experienced a transient ischemic attack or stroke. ... heart attack Severe lung disease or chronic obstructive pulmonary disease Severe renal disease High cervical (C2) or ...
In 2007 Flynn suffered a transient ischaemic attack. Flynn died in Newport, Wales, on 17 February 2019, eight days after his ... "Nato curbs Afghan joint patrols over 'insider' attacks". BBC. 18 September 2012. Retrieved 25 January 2014. Hansard Public ... Philip Hammond of lying to Parliament by saying that military operations in Afghanistan were not reduced following attacks on ...
In some cases stroke and transient ischemic attacks have occurred after sclerotherapy. Varicose veins and reticular veins are ...
At the age of 15, Redmond suffered a transient ischemic attack stroke; as a result, he was forced to relearn how to walk and ...
... refined the definition of transient ischemic attack. TIA is now defined as a transient episode of neurologic dysfunction caused ... Transient ischemic attack (TIA), is often referred to as a "mini-stroke". The American Heart Association and American Stroke ... Sometimes, even an infant that is still in the womb may exhibit signs of HIE or other hypoxic ischemic injury. Fetal distress ... The severity of a neonatal hypoxic-ischaemic brain injury may be assessed using Sarnat staging, which is based on clinical ...
"An Unusual Cause of Transient Ischemic Attack in a Patient with Pacemaker". Case Reports in Cardiology. 2014: 265759. doi: ... Software Radio Attacks and Zero-Power Defenses (PDF). IEEE Symposium on Security and Privacy. Retrieved 2008-08-10. " ...
Transient ischemic attack Spreading depression: discovery Dodick DW & Gargus JJ (August 2008). "Why migraines strike". ...
Differential diagnoses include a transient ischemic attack, intracranial mass, or brain abscess. Epidural hematomas usually ...
Neurologic complications such as transient ischemic attack in 2.5% of the cases. There is also the risk of stroke with ... frequent transient ischemic attacks, age more than 55 years, and poorly controlled diabetes. Besides, longer procedures, ... Tariq N, Khatri R (October 2008). "Leptomeningeal collaterals in acute ischemic stroke". Journal of Vascular and Interventional ...
It is a type of transient ischaemic attack (TIA).[citation needed] Those experiencing amaurosis usually experience complete ...
... s may resemble transient ischemic attacks or, when longer in duration, stroke. The concurrence of other ...
PMID 25346269 Blood-Brain Barrier Leakage - A New Biomarker in Transient Ischemic Attacks. Yonatan Serlin , Jonathan Ofer , Gal ...
Age-associated medical conditions like stroke or transient ischemic attack, glaucoma, and Parkinson's disease. Although the ...
"Guidelines for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack". Stroke. 45 (7): 2160-2236. doi: ...
... and SPECT to investigate the pathophysiology of transient ischemic attacks (TIAs) and acute ischemic stroke, as well as the ... and Normal Magnetic Resonance Imaging in a New Rat Model of True Transient Ischemic Attacks". Stroke. 46 (4): 1084-1092. doi: ... "Refinement of Imaging Predictors of Recurrent Events following Transient Ischemic Attack and Minor Stroke". PLOS ONE. 8 (6): ... His main findings include the discovery of the ischemic penumbra in humans and the crucial role of hemodynamic impairment in ...
People who have had a transient ischemic attack (TIA) or stroke can present with symptoms similar to MD, and in people at risk ... Other conditions that may produce similar symptoms include vestibular migraine and transient ischemic attack. No cure is known ... Attacks are often treated with medications to help with the nausea and anxiety. Measures to prevent attacks are overall poorly ... the tinnitus is more severe before a spell of vertigo and lessens after the vertigo attack. Attacks are characterized by ...
A transient ischemic attack (TIA), commonly known as a mini-stroke, is a minor stroke whose noticeable symptoms usually end in ... Presence of ischemic lesions on diffusion weighted imaging has been correlated with a higher risk of stroke after a TIA. ... TIAs used to be defined as ischemic events in the brain that last less than 24 hours, but given the variation in duration of ... Sometimes, myocardial infarction ("heart attack") may lead to the formation of a blood clot in one of the chambers of the heart ...
A transient ischemic attack (TIA) occurs when blood flow to a part of the brain stops for a brief time. A person will have ... A transient ischemic attack (TIA) occurs when blood flow to a part of the brain stops for a brief time. A person will have ... A transient ischemic attack (TIA) occurs when blood flow to a part of the brain stops for a brief time. A person will have ... A transient ischemic attack is a warning sign that a true stroke may happen in the future (often near future) if something is ...
A transient ischemic attack (TIA) is an acute episode of temporary neurologic dysfunction that results from focal cerebral, ... encoded search term (Transient Ischemic Attack) and Transient Ischemic Attack What to Read Next on Medscape ... Guidelines for prevention of stroke in patients with ischemic stroke or transient ischemic attack: a statement for healthcare ... Diagnostic usefulness of the ABCD2 score to distinguish transient ischemic attack and minor ischemic stroke from ...
... also known as a transient ischemic attack (TIA), involves a temporary loss of blood supply to the brain. Learn more about TIAs ... TIA (transient ischemic attack). (n.d.).. https://www.stroke.org/en/about-stroke/types-of-stroke/tia-transient-ischemic-attack ... Overview: Transient ischaemic attack (TIA). (2020).. https://www.nhs.uk/conditions/transient-ischaemic-attack-tia/. ... A transient ischemic attack (TIA), or ministroke, results from a temporary stoppage in the blood supply to the brain. TIAs ...
... transient ischemic attacks or TIAs. The difference between a transient ischemic attack and a stroke... ... transient ischemic attacks or TIAs. The difference between a transient ischemic attack and a stroke is that the blockage with ... A transient ischemic attack is what occurs when the blood flow to part of the brain is either blocked or reduced. This usually ... Transient Ischemic Attack Essay. 1103 Words , 5 Pages. The symptoms for a TIA are the same as a regular stroke, but last ...
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G45.9 - Transient cerebral ischemic attack, unspecified. SNOMEDCT:. 266257000 - Transient ischemic attack. Look For. Copy. ... A transient ischemic attack (TIA) is a transient episode of acute-onset neurologic symptoms that localize to a specific ... Transient ischemic attacks Print Patient Handout Images (1) Contributors: Ross Hamilton MD, Christine Osborne MD, Richard L. ... Patients with transient symptoms lasting hours that would have formerly been diagnosed with TIA are now being found with ...
Discusses transient ischemic attack (TIA), sometimes called a mini-stroke. Covers causes, including blood clot as a result of ... Transient Ischemic Attack (TIA). Condition Basics. What is a transient ischemic attack (TIA)?. A transient ischemic attack (TIA ...
Transient ischaemic attack (TIA) - information, support and advice from the Brain & Spine Foundation. ... Transient ischaemic attack (TIA). A temporary disruption of the blood flow to an area of the brain, which can affect the ...
... recommendations on the prevention of future stroke among survivors of ischemic stroke or transient ischemic attack. The ... Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare ... Keywords: AHA Scientific Statements; atrial fibrillation; carotid stenosis; hypertension; ischemia; ischemic attack, transient ... recommendations on the prevention of future stroke among survivors of ischemic stroke or transient ischemic attack. The ...
Transient Ischaemic Attack. Warning Signs of Stroke. A stroke may be caused by (a) blockage of a blood vessel within the brain ... Symptoms of Transient Ischaemic Attacks - Warning Strokes. FLEETING BLINDNESS OR BLURRING OF VISION. In one or both eyes, ... subsequently have a stroke due to blockage of a blood vessel have a small warning episode termed a transient ischaemic attack ( ...
You searched for: Subject Transient ischemic attack ✖ Remove constraint Subject: Transient ischemic attack Start Over ... Transient ischemic attackCerebrovascular disease--PatientsPoorMinoritiesDrug utilizationMedicine 5. Prevalence of PTSD in ... Myocardial infarctionTransient ischemic attackEpidemiologyPhysiology, Pathological 2. Correlates of Post-traumatic Stress ... 4. Key Barriers to Medication Adherence in Survivors of Strokes and Transient Ischemic Attacks Kronish, Ian M.; Diefenbach, ...
Background Enhanced secondary preventive follow-up after stroke or transient ischemic attack (TIA) is necessary for improved ... Ischemic stroke Is the Subject Area "Ischemic stroke" applicable to this article? Yes. No. ...
... What is a TIA?. A transient ischemic attack (TIA) means that the blood flow to ... Health Information and Tools , Patient Care Handouts , Learning About Transient Ischemic Attack (TIA) ...
Peoples experiences of the impact of transient ischaemic attack and its consequences: qualitative study. Document first ... Peoples experiences of the impact of transient ischaemic attack and its consequences: qualitative study. NHS England is not ... A study by Gibson and Watkins (2011) explored how peoples experiences of Transient Ischaemic Attack (TIA) affected their ...
Recent trials have evaluated the use of aspirin to prevent stroke after an ischemic stroke or transient ischemic attack (TIA). ... Recent trials have evaluated the use of aspirin to prevent stroke after an ischemic stroke or transient ischemic attack (TIA). ... Aspirin and Ticagrelor in Acute Ischemic Stroke or Transient Ischemic Attack. Aug 7, 2020 ... The research concluded that the risk of stroke or death in ischemic stroke or TIA patients was lower with ticagrelor-aspirin ...
Symptoms of a transient ischaemic attack (TIA). The main symptoms of a TIA can be remembered with the word FAST:. *Face - the ... Preventing a transient ischaemic attack (TIA). A TIA is often a sign that another one may follow and youre at a high risk of ... Causes of a transient ischaemic attack (TIA). During a TIA, 1 of the blood vessels that supply your brain with oxygen-rich ... Treating a transient ischaemic attack (TIA). Although the symptoms of a TIA resolve in a few minutes or hours, youll need ...
... an observation and implementation study investigating optimisation of the management of stroke and transient ischaemic attack ( ... an observation and implementation study investigating optimisation of the management of stroke and transient ischaemic attack ( ... an observation and implementation study investigating optimisation of the management of stroke and transient ischaemic attack ( ...
Missed opportunities for primary prevention of stroke and transient ischaemic attack (TIA) and residual impairments after TIA ... Turner, Grace Mary (2016). Missed opportunities for primary prevention of stroke and transient ischaemic attack (TIA) and ... The research investigated: (i) potential missed opportunities for primary prevention of stroke and transient ischaemic attack ( ... These findings suggest that impairments exist after initial symptoms of TIA have resolved and challenge the transient ...
A simple risk score predicted 7 day stroke risk after transient ischaemic attack ... A simple risk score predicted 7 day stroke risk after transient ischaemic attack ...
Transient Ischemic Attack (TIA) - Etiology, pathophysiology, symptoms, signs, diagnosis & prognosis from the MSD Manuals - ... A transient ischemic attack (TIA) is focal brain ischemia that causes sudden, transient neurologic deficits and is not ... Treatment of transient ischemic attacks is aimed at preventing strokes; antiplatelet medications and statins are used. Carotid ... Transient ischemic attacks are diagnosed retrospectively when sudden neurologic deficits referable to ischemia in an arterial ...
What are the chances of having a transient ischemic attack if you already had one in the past?. 3 doctor answers • 6 doctors ... A transient ischemic attack is often a predecessor to what?. 2 doctor answers • 4 doctors weighed in ... Transient ischemic attack - how long does it usually last?. 3 doctor answers • 5 doctors weighed in ... Is it possible to have a transient ischemic attack in your 20s?. 2 doctor answers • 4 doctors weighed in ...
Long-term morbidity and mortality in patients without early complications after stroke or transient ischaemic attack. *Monique ... paper on "Long-term morbidity and mortality in patients without early complications after stroke or transient ischaemic attack" ... Long-term morbidity and mortality in patients without early complications after stroke or transient ischaemic attack. ...
Downloading a figure as powerpoint requires a browser with javascript support. Enable javascript and try again For help please contact [email protected] ...
Long-term Incidence of Ischemic Stroke Following Transient Ischemic Attack: A Nationwide Study During 2014-2020. Circulation ...
Labels: symptoms of a TIA, syptoms of mini strokes, transcient ischemic strokes, transient ischemic attacks, treatment for a ... Facts about TIA - Transient Ischemic Attacks. * A TIA has similar symptoms to a major stroke, but they usually last only a few ... Treatment for Transient Ischemic Attacks. After a variety of tests to diagnose the cause of your TIA, your doctor will choose a ... www.mayoclinic.org/diseases-conditions/transient-ischemic-attack/basics/definition/con-20021291. For more information on ...
... G. ... Incidence of transient ischemic attacks in the Belluno Province, Italy : First-year results of a community-based study / G. ... 271 patients with a diagnosis of transient ischemic attack were recruited. Among these, we recorded 171 cases of new TIAs. The ... 271 patients with a diagnosis of transient ischemic attack were recruited. Among these, we recorded 171 cases of new TIAs. The ...
A transient ischemic attack (TIA) is a stroke that comes and goes quickly. It happens when the blood supply to part of the ... Home » Health Topics » Transient Ischemic Attack. Transient Ischemic Attack. Health Topics 2,282 Views ...
A transient ischemic attack (TIA) is an acute episode of temporary neurologic dysfunction that results from focal cerebral, ... encoded search term (Transient Ischemic Attack) and Transient Ischemic Attack What to Read Next on Medscape ... Guidelines for prevention of stroke in patients with ischemic stroke or transient ischemic attack: a statement for healthcare ... Diagnostic usefulness of the ABCD2 score to distinguish transient ischemic attack and minor ischemic stroke from ...
  • Depressive Symptoms Following Stroke and Transient Ischemic Attack: Is It Time for a More Intensive Treatment Approach? (psychiatrist.com)
  • Objective Although more than 95% of the population is insured by urban or rural insurance programmes in China, little research has been done on insurance-related outcome disparities for patients with acute stroke and transient ischaemic attack (TIA). (bmj.com)
  • We provide a large-scale, nationwide, prospective, registry project-based study to explore the association between insurance status and 1-year outcome for patients with stroke and transient ischaemic attack. (bmj.com)
  • Gillham, S & Endacott, R 2010, ' Impact of enhanced secondary prevention on health behaviour in patients following minor stroke and transient ischaemic attack: A randomized controlled trial ', Clinical Rehabilitation , vol. 24, no. 9, pp. 822 - 830. (monash.edu)
  • Setting Stroke and transient ischaemic attack services in Lothian, a region of Scotland with a population of 810 000. (sinapse.ac.uk)
  • It has been suggested that transient ischemic attacks (TIAs) are a subset of a larger category termed transient neurologic attacks (TNAs). (medscape.com)
  • TIAs used to be defined as ischemic events in the brain that last less than 24 hours, but given the variation in duration of symptoms, this definition holds less significance. (wikipedia.org)
  • Embolism that briefly obstruct blood circulation to the mind are one of the most usual source of passing ischemic assaults (TIAs). (valleyfamilymedicineurgentcarecenter.com)
  • 13th June 2022 , UHCW will hold TIA (Transient Ischaemic Attack) clinics for all Coventry, Rugby and South Warwickshire patients that have been referred with suspected TIAs. (coventryrugbygpgateway.nhs.uk)
  • A transient ischemic attack (TIA), commonly known as a mini-stroke, is a minor stroke whose noticeable symptoms usually end in less than an hour. (wikipedia.org)
  • A transient ischaemic attack (TIA) or 'mini stroke' is caused by a temporary disruption in the blood supply to part of the brain. (wales.nhs.uk)
  • We found that stroke risk is three times higher in patients who were poor responders to clopidogrel and treated with the drug following a "mini-stroke"-also known as a transient ischemic attack . (nih.gov)
  • If you have already had a stroke or a transient ischemic attack (TIA), also known as a "mini-stroke," your chances of having another stroke are higher. (cdc.gov)
  • Sometimes called a mini-stroke, a transient ischemic attack (TIA) starts with the same symptoms of a full stroke but does not progress and cause the damage of a full stroke. (nih.gov)
  • Tell your doctor if you have ever had a heart attack , stroke, TIA or "mini-stroke", chest pain, severe circulation problems, or a blood clot (especially within the past 3 months). (drugs.com)
  • Stroke Risk and Antithrombotic Treatment During Follow-up of Patients With Ischemic Stroke and Cortical Superficial Siderosis. (nih.gov)
  • Further workup should be considered in patients suffering nonfocal TNAs to elucidate the underlying cause of their transient symptoms and to achieve better risk stratification. (medscape.com)
  • Quality of hospital care in African American and white patients with ischemic stroke and TIA. (medscape.com)
  • In TIA/ischemic stroke patients, the clinical significance of lobar microbleeds potentially indicating cerebral amyloid angiopathy (CAA) is unknown. (hindawi.com)
  • We assessed vascular risk factors and outcomes, including cognition, in TIA/ischemic stroke patients with neuroimaging evidence of probable/possible CAA. (hindawi.com)
  • In total, 291/1620 patients with ischemic stroke/TIA (32.7% female and mean age, 67.8 years) had neuroimaging evidence of probable/possible CAA. (hindawi.com)
  • Higher age, history of hypertension, atrial fibrillation, ischemic stroke, alcohol, and high glucose at the admission were more common in the patients. (hindawi.com)
  • This study suggested that an increasing number of vascular risk factors and imaging markers were significantly associated with outcomes of TIA/ischemic stroke patients with CAA pattern. (hindawi.com)
  • The impact of cerebral amyloid angiopathy to poststroke cognitive impairment and global disability in TIA/ischemic stroke patients is indeterminate. (hindawi.com)
  • Many randomized clinical trials have evaluated the benefit of long-term use of antiplatelet drugs in reducing the risk of new vascular events in patients with a recent transient ischemic attack or ischemic stroke. (nih.gov)
  • We estimated the eligibility for participation in landmark trials of antiplatelet drugs of an unselected group of patients with stroke or transient ischemic attack from a national stroke survey. (nih.gov)
  • Nine hundred seventy-two patients with transient ischemic attack or ischemic stroke were prospectively and consecutively enrolled in the Netherlands Stroke Survey. (nih.gov)
  • Our data confirm that patients with ischemic attack and stroke enrolled in randomized clinical trials are only partially representative of patients in clinical practice. (nih.gov)
  • The present study was designed to measure LA conventional echocardiography and LA strain and strain rate parameters in patients with paroxysmal atrial fibrillation, then to analyze the difference between stroke/ transient ischemic attack (TIA) and non-stroke/TIA patients, and to explore relationship between the impaired deformability of LA and stroke/TIA events and its predictive value for stroke/TIA events. (researchsquare.com)
  • 47 patients of them were found to have had a history of ischemic stroke or TIA. (researchsquare.com)
  • A Randomised, Double-Blind, Multinational Study to Prevent Major Vascular Events with Ticagrelor Compared to Aspirin (ASA) in Patients with Acute Ischaemic Stroke or TIA. (astrazenecaclinicaltrials.com)
  • Problem Patients with transient ischaemic attack or stroke benefit from early diagnosis, specialist assessment, and treatment with thrombolysis, and from stroke unit care and secondary prevention. (sinapse.ac.uk)
  • Strategy for change In February 2007 we introduced a 24 hours a day, seven days a week hotline to a consultant, who provided immediate advice on diagnosis, investigation, and emergency treatment for patients with transient ischaemic attack or stroke, and suggested the most appropriate care pathway, which might include an early appointment in a transient ischaemic attack and stroke clinic. (sinapse.ac.uk)
  • Lessons learnt Although associated with some disruption to the activities of the consultants, a 24 hours a day, seven days a week telephone hotline to a consultant is a feasible and effective means of reducing delays to specialist assessment and treatment of patients with transient ischaemic attack or stroke. (sinapse.ac.uk)
  • A cohort of 469 hospital-referred patients with transient ischaemic attacks (TIA) of the brain (66%) or eye (34%) due to presumed atheromatous thromboembolism, lipohyalinosis or cardiogenic embolism, without prior stroke, was assembled between 1976-86. (edu.au)
  • Scholars@Duke publication: Apixaban compared with warfarin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: a subgroup analysis of the ARISTOTLE trial. (duke.edu)
  • Patients with AF and previous stroke or transient ischaemic attack (TIA) have a high risk of stroke. (duke.edu)
  • Do not use Effient in patients with active pathological bleeding or a history of transient ischemic attack or stroke ( 4.1 , 4.2 ). (nih.gov)
  • Do not use Prasugrel tablets in patients with active pathological bleeding or a history of transient is chemic attack or stroke ( 4.1 , 4.2 ). (nih.gov)
  • We aimed to determine the accuracy of the NTS urgency allocation for patients with neurological symptoms suggestive of a transient ischaemic attack (TIA) or stroke, with the clinical outcomes TIA, stroke, and other (neurologic) life-threatening events (LTEs) as the reference. (biomedcentral.com)
  • Of 1269 patients, 635 (50.0%) received the diagnosis TIA/stroke (34.2% TIA/minor stroke, 15.8% major ischaemic or haemorrhagic stroke), and 4.8% other LTEs. (biomedcentral.com)
  • This study was undertaken to investigate whether high- sensitivity cardiac troponin T (hs-cTnT) is associated with major adverse cardiovascular events ( MACE ) in patients with minor stroke or transient ischemic attack (TIA), and whether this association differs after risk stratification based on the Age, Blood Pressure , Clinical Features, Duration of Symptoms, Diabetes (ABCD2 ) score. (bvsalud.org)
  • The perindopril protection against recurrent stroke study (PROGRESS) was designed to determine the effects of a blood-pressure-lowering regimen in hypertensive and non-hypertensive patients with a history of stroke or transient ischaemic attack. (ox.ac.uk)
  • Treatment with these two agents should now be considered routinely for patients with a history of stroke or transient ischaemic attack, irrespective of their blood pressure. (ox.ac.uk)
  • More than one-half of the patients in each arm of the trial had experienced a previous stroke, embolism, or transient ischemic attack. (aafp.org)
  • Non-focal symptoms such as amnesia, confusion, incoordination of limbs, unusual cortical visual symptoms (such as isolated bilateral blindness or bilateral positive visual phenomena), headaches and transient loss of consciousness are usually not associated with TIA, however patient assessment is still needed. (wikipedia.org)
  • To examine whether depressive symptoms after a stroke or a transient ischemic attack (TIA) increase the risk of cognitive impairment and functional deterioration at 2-year follow-up. (psychiatrist.com)
  • The symptoms of a transient ischaemic attack (TIA) are the same as those of a stroke , but they only last for a few minutes or hours. (wales.nhs.uk)
  • The symptoms of a transient ischemic attack (TIA) are similar to those of a more serious stroke, but unlike a serious stroke, a TIA usually lasts only a few minutes and goes away within an hour. (nih.gov)
  • 1.1.1 Use a validated tool, such as FAST (Face Arm Speech Test), outside hospital to screen people with sudden onset of neurological symptoms for a diagnosis of stroke or transient ischaemic attack (TIA). (coventryrugbygpgateway.nhs.uk)
  • The atorvastatin group had 218 ischemic strokes and 55 hemorrhagic strokes, whereas the placebo group had 274 ischemic strokes and 33 hemorrhagic strokes. (nih.gov)
  • Strokes are caused by blocked blood flow to the brain (ischemic stroke) or sudden bleeding in the brain (hemorrhagic stroke). (nih.gov)
  • Incidence and short-term prognosis of transient ischemic attack in a population-based study. (medscape.com)
  • Prognosis of transient ischemic attacks in the Oxfordshire Community Stroke Project. (jamanetwork.com)
  • Ischemic strokes are classified specifically based on where in the brain the blockage occurs and where in the body an embolism developed. (nih.gov)
  • A passing ischemic assault (TIA) takes place when blood circulation to component of the mind is obstructed or lowered, typically by a blood embolism. (valleyfamilymedicineurgentcarecenter.com)
  • However, there are few data on the costs and outcomes of urgent assessment and treatment after the onset of transient ischaemic attack (TIA) or minor stroke. (ox.ac.uk)
  • About 87% of strokes are ischemic. (nih.gov)
  • Ischemic strokes make up about 87% of all strokes. (nih.gov)
  • Diagnosis, Workup, Risk Reduction of Transient Ischemic Attack in the Emergency Department Setting: A Scientific Statement From the American Heart Association. (nih.gov)
  • Giles MF, Rothwell PM. Risk of stroke early after transient ischaemic attack: a systematic review and meta-analysis. (medscape.com)
  • Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack. (medscape.com)
  • whether they reduce the risk of stroke after a recent stroke or transient ischemic attack (TIA) remains to be established. (nih.gov)
  • The evaluation of the interactive effects of vascular risk and imaging markers is more important to the outcome of neuroimaging evidence of CAA pattern in ischemic intracerebral events (TIA and ischemic stroke). (hindawi.com)
  • Good blood pressure (BP) control reduces the risk of recurrence of stroke/transient ischaemic attack (TIA). (nih.gov)
  • Risk factors for TIA are the same as those for ischemic stroke. (msdmanuals.com)
  • Population based study of early risk of stroke after transient ischaemic attack or minor stroke: implications for public education and organisation of services. (jamanetwork.com)
  • One-year risk of stroke after transient ischemic attack or minor stroke. (jamanetwork.com)
  • A simple score (ABCD) to identify individuals at high early risk of stroke after transient ischaemic attack. (jamanetwork.com)
  • Transient ischemic attack (TIA) can confer a high risk of stroke immediately post-event with an average 11·0% risk during the first 7 days [ 1 ]. (biomedcentral.com)
  • INTERPRETATION: This blood-pressure-lowering regimen reduced the risk of stroke among both hypertensive and non-hypertensive individuals with a history of stroke or transient ischaemic attack. (ox.ac.uk)
  • A transient ischemic attack (TIA) is defined as the sudden onset of a neurologic deficit that resolves completely within 24 hours. (health.am)
  • Cardiac Troponin and Recurrent Major Vascular Events after Minor Stroke or Transient Ischemic Attack. (bvsalud.org)
  • Sickle cell disease is a blood disorder linked to ischemic stroke that affects mainly Black children. (cdc.gov)
  • One of the drug-gene interactions that I found most interesting is related to clopidogrel, a drug commonly prescribed to keep arteries open after a major cardiovascular event, like a heart attack, stroke, or placement of a stent. (nih.gov)
  • Cognitive impairment and degree of global disability after TIA or ischemic stroke is the most common outcome in some clinical trials. (hindawi.com)
  • Participants were survivors of first-ever, mild-to-moderate ischemic stroke or TIA from the TABASCO prospective cohort study who underwent 3T magnetic resonance imaging and were examined by a multiprofessional team 6, 12, and 24 months after the event using direct interviews, depression scales, and neurologic, neuropsychological, and functional evaluations. (psychiatrist.com)
  • A transient ischemic attack (TIA) occurs when blood flow to a part of the brain stops for a brief time. (medlineplus.gov)
  • Ischemic Stroke Ischemic stroke is sudden neurologic deficits that result from focal cerebral ischemia associated with permanent brain infarction (eg, positive results on diffusion-weighted MRI). (msdmanuals.com)
  • The illustration shows how an ischemic stroke can occur in the brain. (nih.gov)
  • Ischemic stroke can also lead to inflammation that further damages brain cells. (nih.gov)
  • A transient ischemic attack (TIA) is caused by a blockage in the brain just like an ischemic stroke. (nih.gov)
  • Ischemic stroke happens when an artery carrying blood to the brain becomes blocked and cannot supply enough blood to the brain. (nih.gov)
  • TIA or Transient Ischemic Attack is defined by the American Stroke Association as "a temporary blockage of blood flow to the brain. (fcppcentralvalley.com)
  • Ischemic stroke is caused by a blood clot that blocks or plugs a blood vessel in the brain. (nih.gov)
  • Carotid artery disease is similar to coronary artery disease, in which blockages occur in the arteries of the heart, and may cause a heart attack. (cooperhealth.org)
  • Clinical manifestations of carotid artery occlusive disease include contralateral weakness or sensory loss, expressive aphasia, and amaurosis fugax (transient partial or complete loss of vision in the ipsilateral eye). (health.am)
  • Dipping Pattern and 1-year stroke functional outcome in ischemic stroke or transient ischemic attack. (nih.gov)
  • Triglyceride-glucose index as a prognostic marker after ischemic stroke or transient ischemic attack: a prospective observational study. (nih.gov)
  • Design An ongoing prospective audit of a transient ischaemic attack and stroke clinic (1 January 2005 to 30 September 2009), as part of the Scottish Stroke Care Audit, and a three month targeted audit of immediate telephone access to a specialist stroke consultant (1 February 2009 to 30 April 2009). (sinapse.ac.uk)
  • Effect of urgent treatment for transient ischaemic attack and minor stroke on disability and hospital costs (EXPRESS study): a prospective population-based sequential comparison. (ox.ac.uk)
  • Dhamoon MS, Sciacca RR, Rundek T, Sacco RL, Elkind MS. Recurrent stroke and cardiac risks after first ischemic stroke: the Northern Manhattan Study. (medscape.com)
  • In this paper the neural network model for transient ischemic attacks recognition have been addressed. (bstu.by)
  • Combining two different neural networks (NPCA and MLP) it is possible to produce efficient performance in terms of detection and recognition transient ischemic attacks. (bstu.by)
  • From the Ad Hoc Committee on Guidelines for the Management of Transient Ischemic Attacks of the Stroke Council of the American Heart Association. (jamanetwork.com)
  • AHA Scientific Statement: supplement to the guidelines for the management of transient ischemic attacks: a statement from the Ad Hoc Committee on Guidelines for the Management of Transient Ischemic Attacks, Stroke Council, American Heart Association. (jamanetwork.com)
  • Studies have found ischemic stroke in people who have COVID-19. (nih.gov)
  • In some individuals, a transient ischemic attack may be a warning sign that a stroke may occur in the future. (endovascularsurgery.com)
  • Transient Ischaemic Attack (TIA) requires urgent investigation and management. (biomedcentral.com)
  • Edlow JA, Kim S, Pelletier AJ, Camargo CA Jr. National study on emergency department visits for transient ischemic attack, 1992-2001. (medscape.com)
  • The main advantages of using neural network techniques are the ability to recognize "novel" TIA attack instances, quickness and ability to assist the doctor in making decision. (bstu.by)
  • Randomised trial of a perindopril-based blood-pressure-lowering regimen among 6,105 individuals with previous stroke or transient ischaemic attack. (ox.ac.uk)
  • Ischemic stroke subtype incidence among whites, blacks, and Hispanics: the Northern Manhattan Study. (medscape.com)
  • Transient means temporary and ischaemia is the medical term for an inadequate supply of blood. (brainandspine.org.uk)
  • Getting the right treatment on the first try could cut my chances of a heart attack in half. (nih.gov)
  • A transient ischemic attack is a warning sign that a true stroke may happen in the future (often near future) if something is not done to prevent it. (medlineplus.gov)