Brain Infarction
Cerebral Infarction
Infarction
Myocardial Infarction
Brain Ischemia
Intracranial Embolism and Thrombosis
Stroke, Lacunar
Cerebrovascular Disorders
Ischemic Attack, Transient
Leukoaraiosis
Magnetic Resonance Imaging
Infarction, Middle Cerebral Artery
Brain
Stroke
Risk Factors
Intracranial Embolism
Brain Chemistry
Brain Edema
Intracranial Arteriosclerosis
Brain Injuries
Tomography, X-Ray Computed
Brain Neoplasms
Cerebral Hemorrhage
Brain Mapping
Disease Models, Animal
Neuroprotective Agents
Prospective Studies
Cerebral Angiography
Case-Control Studies
Treatment Outcome
Risk
Electrocardiography
Hypertension
Incidence
Risk Assessment
Magnetic Resonance Angiography
Rats, Sprague-Dawley
Diffusion Magnetic Resonance Imaging
Predictive Value of Tests
Angioplasty, Balloon, Coronary
Japan
Thrombolytic Therapy
Carotid Stenosis
Retrospective Studies
Splenic Infarction
Coronary Angiography
Anterior Wall Myocardial Infarction
Age Factors
Sex Factors
Brain Stem
Multivariate Analysis
Ventricular Remodeling
Myocardial Reperfusion
Brain Stem Infarctions
Odds Ratio
Cohort Studies
Myocardium
Creatine Kinase
Streptokinase
Prevalence
Follow-Up Studies
Prognosis
Brain Abscess
Ventricular Function, Left
Coronary Care Units
Coronary Disease
Angina Pectoris
Platelet Aggregation Inhibitors
Alcohol Drinking
Cerebral Cortex
Myocardial Ischemia
Biological Markers
Echocardiography
Neurons
Hypoxia, Brain
Blood-Brain Barrier
Stents
Myocardial Revascularization
Inferior Wall Myocardial Infarction
Ventricular Dysfunction, Left
Stroke Volume
Coronary Thrombosis
Percutaneous Coronary Intervention
Rats, Wistar
Hospital Mortality
Coronary Artery Disease
Brain Damage, Chronic
Heart Failure
Tomography, Emission-Computed, Single-Photon
Heart Ventricles
Image Processing, Computer-Assisted
Tissue Plasminogen Activator
Registries
Coronary Artery Bypass
Proportional Hazards Models
Survival Analysis
Aspirin
Analysis of Variance
Hemodynamics
Sensitivity and Specificity
Arrhythmias, Cardiac
Mice, Inbred C57BL
Natriuretic Peptide, Brain
Acute Coronary Syndrome
Clinical Enzyme Tests
Heart Rupture, Post-Infarction
Survival Rate
Cardiac Catheterization
Diffusion-weighted MRI in acute lacunar syndromes. A clinical-radiological correlation study. (1/678)
BACKGROUND AND PURPOSE: Clinical-radiological correlation studies in lacunar syndromes have been handicapped by the low sensitivity of CT and standard MRI for acute small-vessel infarction and their difficulty in differentiating between acute and chronic lesions. METHODS: We prospectively studied 43 patients presenting with a classic lacunar syndrome using diffusion-weighted MRI, a technique with a high sensitivity and specificity for acute small-vessel infarction. RESULTS: All patients were scanned within 6 days of stroke onset. An acute infarction was identified in all patients. Pure motor stroke was associated with lesions in the posterior limb of the internal capsule (PLIC), pons, corona radiata, and medial medulla; ataxic hemipareses with lesions in the PLIC, corona radiata, pons, and insular cortex; sensorimotor stroke with lesions in the PLIC and lateral medulla; dysarthria-clumsy hand syndrome with lesions in the PLIC and caudate nucleus; and pure sensory stroke with a lesion in the thalamus. Supratentorial lesions extended into neighboring anatomic structures in 48% of the patients. CONCLUSIONS: Lacunar syndromes can be caused by lesions in a variety of locations, and specific locations can cause a variety of lacunar syndromes. Extension of lesions into neighboring structures in patients with lacunar syndromes appears to be more frequent than previously described in studies using CT and standard MRI. (+info)Neonatal focal temporal lobe or atrial wall haemorrhagic infarction. (2/678)
AIMS: To describe two variants of infarction within the temporal lobe, associated with local matrix bleeding and mild to moderate intraventricular haemorrhage. METHODS: The files of 10 neonates, extracted from a sonographic study of 560 very low birthweight infants conducted between 1993 and 1997, were retrospectively examined. RESULTS: Seven lesions were located in the middle to posterior area of the temporal lobe, three others faced the atrium. All except two of those with a temporal site were VLBW infants with hyaline membrane disease. Except for one fatal case, intraventricular bleeding was mild to moderate. Computed tomograms or magnetic resonance imaging were used to illustrate the haemorrhagic nature of three lesions. Survivors of this so far undescribed entity who were followed up for more than 18 months did not have a uniform type of cerebral palsy but some scored in the low normal range on the Bayley Mental Development Index. One girl developed temporal lobe epilepsy. CONCLUSIONS: This pattern of injury seems to be one of venous infarction associated with temporal or para-atrial matrix haemorrhage. The temporal site fits the picture of venous infarction within the area drained by the inferior ventricular vein. A less constant lateral atrial vein, either draining into the basal or internal cerebral vein, is probably involved in the para-atrial lesion. Sonography may be the only practical tool currently available for detection in life. (+info)Primary somatosensory cortex activation is not altered in patients with ventroposterior thalamic lesions: a PET study. (3/678)
BACKGROUND AND PURPOSE: We know remarkably little about the mechanisms underlying cortical activation. Such mechanisms might be better understood by studying the effect of well-localized lesions on the cortical activations in simple paradigms. METHODS: We used H(2)(15)O and positron emission tomography to measure regional cerebral blood flow (rCBF) at rest and during hand vibration in 7 patients with unilateral thalamic lesion involving the ventroposterior (VP) somatosensory thalamic relay nuclei. We compared the results with those obtained in 6 patients with thalamic lesions sparing the VP nuclei and 6 healthy controls. RESULTS: The patients with VP lesions had a selective hypoperfusion at rest in the ipsilesional primary sensorimotor cortex (SM1). This hypoperfusion was significantly correlated with the degree of contralateral somatosensory deficit. This abnormality may reflect the deafferentation of SM1 from its somatosensory thalamic input. Despite this deafferentation, the ipsilesional SM1 was normally activated by the vibration of the hypoesthetic hand. CONCLUSIONS: The fact that a lesion of the somatosensory thalamic relay nuclei alters the rCBF at rest in SM1 but not its activation by hand vibration indicates that the mechanism of cortical activation is complex, even in the case of simple sensory stimulation. In addition, a dissociation may occur between obvious neurological deficits and apparently normal activation patterns, which suggests that activation studies should be interpreted cautiously in patients with focal brain lesions. (+info)High-resolution EEG in poststroke hemiparesis can identify ipsilateral generators during motor tasks. (4/678)
BACKGROUND AND PURPOSE: Multimodal neuroimaging with positron emission tomography (PET) scanning or functional MRI can detect and display functional reorganization of the brain's motor control in poststroke hemiplegia. We undertook a study to determine whether the new modality of 128-electrode high-resolution EEG, coregistered with MRI, could detect changes in cortical motor control in patients after hemiplegic stroke. METHODS: We recorded movement-related cortical potentials with left and right finger movements in 10 patients with varying degrees of recovery after hemiplegic stroke. All patients were male, and time since stroke varied from 6 to 144 months. All patients were right-handed. There was also a comparison group of 20 normal control subjects. RESULTS: Five of 8 patients with left hemiparesis had evidence of ipsilateral motor control of finger movements. There were only 2 cases of right hemiparesis; in addition, 1 patient had a posteriorly displaced motor potential originating behind a large left frontal infarct (rim). CONCLUSIONS: Reorganization of motor control takes place after stroke and may involve the ipsilateral or contralateral cortex, depending on the site and size of the brain lesion and theoretically, the somatotopic organization of the residual pyramidal tracts. Our results are in good agreement with PET and functional MRI studies in the current literature. High-resolution EEG coregistered with MRI is a noninvasive imaging technique capable of displaying cortical motor reorganization. (+info)Experimental model of small deep infarcts involving the hypothalamus in rats: changes in body temperature and postural reflex. (5/678)
BACKGROUND AND PURPOSE: Intraluminal middle cerebral artery (MCA) occlusion in rats has been reported to cause hyperthermia assumed to be caused by hypothalamic damage. To clarify the effects of hypothalamic ischemia on body temperature and to obtain a model simulating lacunar infarction, we attempted to produce small infarcts in deep structures (including the hypothalamus). METHODS: A surgical suture was advanced to occlude the origin of the hypothalamic (HTA) and/or anterior choroidal arteries (AChA) without compromise of the anterior or middle cerebral artery origins. After treatment, rectal temperature and postural reflex were examined repeatedly for 3 days under nonanesthetic conditions. The AChA and HTA and their link with small deep infarction were then confirmed by TTC, hematoxylin and eosin, and TUNEL stains and by microsurgical dissection after colored silicone perfusion into the cerebral arteries. RESULTS: Advancement of the suture near to but not occluding the MCA origin (0.5 to 1.9 mm proximal) produced small, deep, nonneocortical strokes in 25 of 36 animals without producing MCA ischemic changes. These infarctions mainly affected the hypothalamus in 13 animals (HTA area: infarct volume 6+/-1 mm(3)) and involved both the internal capsule and hypothalamus in 12 animals (HTA+AChA area infarct volume 48+/-10 mm(3)). Rats with HTA infarction alone exhibited persistent hyperthermia for 72 hours; some also had transient mild postural abnormality. The AChA+HTA infarct group showed a transient elevation of body temperature for 24 hours and definitive postural abnormality. In the remaining 11 animals, the suture was inadvertently advanced across the MCA origin, producing a large infarct that affected both the neocortex (MCA territory) and nonneocortical structures (volume 381+/-30 mm(3), n=11). The MCA infarct group displayed a transient hyperthermia and severe postural abnormality. CONCLUSIONS: When properly positioned, the intraluminal suture method permits selective AChA and/or HTA obstruction without inducing MCA territory ischemia. This model confirms that selective hypothalamic infarction produces significant and sustained temperature regulation abnormalities. The model also may be useful in investigating the pathophysiology of small, deep, end-vessel infarction. (+info)The association between the Val34Leu polymorphism in the factor XIII gene and brain infarction. (6/678)
Factor XIII catalyzes the formation of covalent bounds between fibrin monomers, thus stabilizing the fibrin clot and increasing its resistance to fibrinolysis. The frequency of a frequent Val34Leu polymorphism in the FXIII A-subunit gene has been shown to be lower in patients with myocardial infarction or venous thrombosis than in controls, whereas it was higher in patients with hemorrhagic stroke than in controls. Our aim was to study the relation between brain infarction (BI) and the FXIII Val34Leu polymorphism in 456 patients consecutively recruited with a BI confirmed by MRI, and 456 matched controls. The distribution of genotypes was different in cases (63. 2% Val/Val; 30.9% Val/Leu; 5.9% Leu/Leu) compared with controls (49. 8% Val/Val; 42.8% Val/Leu; 7.4% Leu/Leu; P <.001). Carrying the Leu allele was associated with an OR of 0.58 (95% CI = 0.44-0.75). A similar association was observed in cases and controls free of previous cardiovascular or cerebrovascular history (OR = 0.51; 95% CI = 0.36-0.73). No heterogeneity of this association was observed after stratification on the main BI subtypes. Adjustment for traditional vascular risk factors did not modify these findings. In addition, the effect of smoking was modified by the polymorphism (P =.05); the effect of smoking was weaker among Leu carriers than among noncarriers. In conclusion, there was a negative association of the FXIII Val34Leu polymorphism with BI, thus suggesting a protective effect of the Leu allele against thrombotic cerebral artery occlusion. In addition, our results suggest that among Leu carriers, the protective effect of the polymorphism outweighed the effect of smoking. (Blood. 2000;95:586-591) (+info)Stroke incidence and case fatality in Shiga, Japan 1989-1993. (7/678)
BACKGROUND: This paper describes incidence rates and case-fatality for sub-types of stroke using data collected in Takashima, Shiga, Japan, from 1989 to 1993 and compares these with similar registers in other parts of Japan. METHODS: Registered patients included all residents of the county who experienced a first-ever stroke. Stroke was defined as sudden onset of neurological symptoms which continued for a minimum of 24 hours or led to death. Almost all such patients are hospitalized in this country. Early case fatality was defined as patients who died within 28 days of stroke onset. Diagnosis of stroke type was based on clinical symptoms as well as computed tomography (CT) scans. RESULTS: Age-adjusted incidence rates for stroke per 100,000 population aged 35 years and older were 268.7 for men and 167.5 for women. The age-specific incidence rate of both cerebral infarction and cerebral haemorrhage increased with advancing age. The occurrence of cerebral infarction in men was twice as high as in women. The 28-day case fatality for all sub-types of stroke was 16.1% in men and 15.8% in women. Case fatality for cerebral infarction, cerebral haemorrhage, and subarachnoid haemorrhage was 10.7%, 22.4% and 28.6% respectively. CONCLUSIONS: Takashima County has a moderately high stroke incidence rate and case fatality compared with other similar studies in Japan. The incidence rate of cerebral infarction in men is twice that in women, while other sub-types of stroke showed smaller differences. In order to decrease the incidence of stroke in Japan, greater efforts at primary prevention will be necessary, in particular, it is important to prevent cerebral infarction in men. (+info)Knowing no fear. (8/678)
People with brain injuries involving the amygdala are often poor at recognizing facial expressions of fear, but the extent to which this impairment compromises other signals of the emotion of fear has not been clearly established. We investigated N.M., a person with bilateral amygdala damage and a left thalamic lesion, who was impaired at recognizing fear from facial expressions. N.M. showed an equivalent deficit affecting fear recognition from body postures and emotional sounds. His deficit of fear recognition was not linked to evidence of any problem in recognizing anger (a common feature in other reports), but for his everyday experience of emotion N.M. reported reduced anger and fear compared with neurologically normal controls. These findings show a specific deficit compromising the recognition of the emotion of fear from a wide range of social signals, and suggest a possible relationship of this type of impairment with alterations of emotional experience. (+info)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.
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.
Infarction is the term used in medicine to describe the death of tissue (also known as an "area of necrosis") due to the lack of blood supply. This can occur when a blood vessel that supplies oxygen and nutrients to a particular area of the body becomes blocked or obstructed, leading to the deprivation of oxygen and nutrients necessary for the survival of cells in that region.
The blockage in the blood vessel is usually caused by a clot (thrombus) or an embolus, which is a small particle that travels through the bloodstream and lodges in a smaller vessel. The severity and extent of infarction depend on several factors, including the size and location of the affected blood vessel, the duration of the obstruction, and the presence of collateral circulation (alternative blood vessels that can compensate for the blocked one).
Common examples of infarctions include myocardial infarction (heart attack), cerebral infarction (stroke), and pulmonary infarction (lung tissue death due to obstruction in the lung's blood vessels). Infarctions can lead to various symptoms, depending on the affected organ or tissue, and may require medical intervention to manage complications and prevent further damage.
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).
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.
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.
A lacunar stroke, also known as a small deep infarct or "lacune," is a type of cerebral infarction that results from the occlusion of one of the penetrating arteries that supply blood to the deep structures of the brain. These strokes are typically caused by lipohyalinosis or fibrinoid necrosis of the small vessels, and they tend to occur in people with underlying cerebral small vessel disease.
Lacunar strokes are often clinically silent, meaning that they do not cause any noticeable symptoms. However, when symptoms do occur, they may include weakness or numbness on one side of the body, difficulty speaking or understanding speech, and problems with coordination or balance. These symptoms can be similar to those caused by other types of stroke, but lacunar strokes tend to affect deeper structures of the brain and are less likely to cause severe neurological deficits.
Diagnosis of a lacunar stroke typically involves imaging studies such as MRI or CT scans, which can show areas of damage in the deep white matter of the brain. Treatment for lacunar strokes is similar to that for other types of stroke and may include medications to prevent blood clots, manage risk factors such as high blood pressure and diabetes, and improve symptoms such as weakness or difficulty walking.
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.
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.
Leukoaraiosis is a medical term that describes the appearance of small-vessel disease in the brain, which can be seen on imaging studies such as MRI or CT scans. It is characterized by areas of increased signal intensity or lucency in the white matter of the brain, particularly in the periventricular and deep white matter regions. These changes are thought to be due to ischemic damage from reduced blood flow in the small vessels of the brain.
Leukoaraiosis is often associated with aging and is more common in people with certain risk factors such as hypertension, diabetes, smoking, and hyperlipidemia. It has been linked to an increased risk of cognitive decline, gait disturbances, and stroke. However, the relationship between leukoaraiosis and these outcomes is complex and not fully understood.
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.
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.
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.
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.
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.
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.
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.
Brain chemistry refers to the chemical processes that occur within the brain, particularly those involving neurotransmitters, neuromodulators, and neuropeptides. These chemicals are responsible for transmitting signals between neurons (nerve cells) in the brain, allowing for various cognitive, emotional, and physical functions.
Neurotransmitters are chemical messengers that transmit signals across the synapse (the tiny gap between two neurons). Examples of neurotransmitters include dopamine, serotonin, norepinephrine, GABA (gamma-aminobutyric acid), and glutamate. Each neurotransmitter has a specific role in brain function, such as regulating mood, motivation, attention, memory, and movement.
Neuromodulators are chemicals that modify the effects of neurotransmitters on neurons. They can enhance or inhibit the transmission of signals between neurons, thereby modulating brain activity. Examples of neuromodulators include acetylcholine, histamine, and substance P.
Neuropeptides are small protein-like molecules that act as neurotransmitters or neuromodulators. They play a role in various physiological functions, such as pain perception, stress response, and reward processing. Examples of neuropeptides include endorphins, enkephalins, and oxytocin.
Abnormalities in brain chemistry can lead to various neurological and psychiatric conditions, such as depression, anxiety disorders, schizophrenia, Parkinson's disease, and Alzheimer's disease. Understanding brain chemistry is crucial for developing effective treatments for these conditions.
Brain edema is a medical condition characterized by the abnormal accumulation of fluid in the brain, leading to an increase in intracranial pressure. This can result from various causes, such as traumatic brain injury, stroke, infection, brain tumors, or inflammation. The swelling of the brain can compress vital structures, impair blood flow, and cause neurological symptoms, which may range from mild headaches to severe cognitive impairment, seizures, coma, or even death if not treated promptly and effectively.
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.
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.
A brain injury is defined as damage to the brain that occurs following an external force or trauma, such as a blow to the head, a fall, or a motor vehicle accident. Brain injuries can also result from internal conditions, such as lack of oxygen or a stroke. There are two main types of brain injuries: traumatic and acquired.
Traumatic brain injury (TBI) is caused by an external force that results in the brain moving within the skull or the skull being fractured. Mild TBIs may result in temporary symptoms such as headaches, confusion, and memory loss, while severe TBIs can cause long-term complications, including physical, cognitive, and emotional impairments.
Acquired brain injury (ABI) is any injury to the brain that occurs after birth and is not hereditary, congenital, or degenerative. ABIs are often caused by medical conditions such as strokes, tumors, anoxia (lack of oxygen), or infections.
Both TBIs and ABIs can range from mild to severe and may result in a variety of physical, cognitive, and emotional symptoms that can impact a person's ability to perform daily activities and function independently. Treatment for brain injuries typically involves a multidisciplinary approach, including medical management, rehabilitation, and supportive 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.
Brain neoplasms, also known as brain tumors, are abnormal growths of cells within the brain. These growths can be benign (non-cancerous) or malignant (cancerous). Benign brain tumors typically grow slowly and do not spread to other parts of the body. However, they can still cause serious problems if they press on sensitive areas of the brain. Malignant brain tumors, on the other hand, are cancerous and can grow quickly, invading surrounding brain tissue and spreading to other parts of the brain or spinal cord.
Brain neoplasms can arise from various types of cells within the brain, including glial cells (which provide support and insulation for nerve cells), neurons (nerve cells that transmit signals in the brain), and meninges (the membranes that cover the brain and spinal cord). They can also result from the spread of cancer cells from other parts of the body, known as metastatic brain tumors.
Symptoms of brain neoplasms may vary depending on their size, location, and growth rate. Common symptoms include headaches, seizures, weakness or paralysis in the limbs, difficulty with balance and coordination, changes in speech or vision, confusion, memory loss, and changes in behavior or personality.
Treatment for brain neoplasms depends on several factors, including the type, size, location, and grade of the tumor, as well as the patient's age and overall health. Treatment options may include surgery, radiation therapy, chemotherapy, targeted therapy, or a combination of these approaches. Regular follow-up care is essential to monitor for recurrence and manage any long-term effects of treatment.
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.
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.
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).
Brain mapping is a broad term that refers to the techniques used to understand the structure and function of the brain. It involves creating maps of the various cognitive, emotional, and behavioral processes in the brain by correlating these processes with physical locations or activities within the nervous system. Brain mapping can be accomplished through a variety of methods, including functional magnetic resonance imaging (fMRI), positron emission tomography (PET) scans, electroencephalography (EEG), and others. These techniques allow researchers to observe which areas of the brain are active during different tasks or thoughts, helping to shed light on how the brain processes information and contributes to our experiences and behaviors. Brain mapping is an important area of research in neuroscience, with potential applications in the diagnosis and treatment of neurological and psychiatric disorders.
Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.
The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.
Examples of animal disease models include:
1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.
Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.
Neuroprotective agents are substances that protect neurons or nerve cells from damage, degeneration, or death caused by various factors such as trauma, inflammation, oxidative stress, or excitotoxicity. These agents work through different mechanisms, including reducing the production of free radicals, inhibiting the release of glutamate (a neurotransmitter that can cause cell damage in high concentrations), promoting the growth and survival of neurons, and preventing apoptosis (programmed cell death). Neuroprotective agents have been studied for their potential to treat various neurological disorders, including stroke, traumatic brain injury, Parkinson's disease, Alzheimer's disease, and multiple sclerosis. However, more research is needed to fully understand their mechanisms of action and to develop effective therapies.
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.
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.
A case-control study is an observational research design used to identify risk factors or causes of a disease or health outcome. In this type of study, individuals with the disease or condition (cases) are compared with similar individuals who do not have the disease or condition (controls). The exposure history or other characteristics of interest are then compared between the two groups to determine if there is an association between the exposure and the disease.
Case-control studies are often used when it is not feasible or ethical to conduct a randomized controlled trial, as they can provide valuable insights into potential causes of diseases or health outcomes in a relatively short period of time and at a lower cost than other study designs. However, because case-control studies rely on retrospective data collection, they are subject to biases such as recall bias and selection bias, which can affect the validity of the results. Therefore, it is important to carefully design and conduct case-control studies to minimize these potential sources of bias.
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.
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.
Electrocardiography (ECG or EKG) is a medical procedure that records the electrical activity of the heart. It provides a graphic representation of the electrical changes that occur during each heartbeat. The resulting tracing, called an electrocardiogram, can reveal information about the heart's rate and rhythm, as well as any damage to its cells or abnormalities in its conduction system.
During an ECG, small electrodes are placed on the skin of the chest, arms, and legs. These electrodes detect the electrical signals produced by the heart and transmit them to a machine that amplifies and records them. The procedure is non-invasive, painless, and quick, usually taking only a few minutes.
ECGs are commonly used to diagnose and monitor various heart conditions, including arrhythmias, coronary artery disease, heart attacks, and electrolyte imbalances. They can also be used to evaluate the effectiveness of certain medications or treatments.
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.
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.
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.
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.
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.
Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.
Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.
These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.
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.
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.
Coronary balloon angioplasty is a minimally invasive medical procedure used to widen narrowed or obstructed coronary arteries (the blood vessels that supply oxygen-rich blood to the heart muscle) and improve blood flow to the heart. This procedure is typically performed in conjunction with the insertion of a stent, a small mesh tube that helps keep the artery open.
During coronary balloon angioplasty, a thin, flexible catheter with a deflated balloon at its tip is inserted into a blood vessel, usually through a small incision in the groin or arm. The catheter is then guided to the narrowed or obstructed section of the coronary artery. Once in position, the balloon is inflated to compress the plaque against the artery wall and widen the lumen (the inner space) of the artery. This helps restore blood flow to the heart muscle.
The procedure is typically performed under local anesthesia and conscious sedation to minimize discomfort. Coronary balloon angioplasty is a relatively safe and effective treatment for many people with coronary artery disease, although complications such as bleeding, infection, or re-narrowing of the artery (restenosis) can occur in some cases.
I'm sorry for any confusion, but "Japan" is not a medical term. Japan is the name of a country, officially known as Nippon-koku or Nihon-koku in Japanese, and is located in East Asia. It is an island nation in the Pacific Ocean with a population of about 126 million people.
If you have any medical questions or terms that you would like me to define, please let me know!
Thrombolytic therapy, also known as thrombolysis, is a medical treatment that uses medications called thrombolytics or fibrinolytics to dissolve or break down blood clots (thrombi) in blood vessels. These clots can obstruct the flow of blood to vital organs such as the heart, lungs, or brain, leading to serious conditions like myocardial infarction (heart attack), pulmonary embolism, or ischemic stroke.
The goal of thrombolytic therapy is to restore blood flow as quickly and efficiently as possible to prevent further damage to the affected organ and potentially save lives. Commonly used thrombolytic drugs include alteplase (tPA), reteplase, and tenecteplase. It's essential to administer these medications as soon as possible after the onset of symptoms for optimal treatment outcomes. However, there are risks associated with thrombolytic therapy, such as an increased chance of bleeding complications, which must be carefully weighed against its benefits in each individual case.
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.
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.
Splenic infarction is the death of splenic tissue due to blockage of its arterial supply or, less commonly, its venous drainage. This results in ischemia and necrosis of the affected portion of the spleen. The most common cause is embolism from a distant source such as atrial fibrillation, infective endocarditis, or malignancy. Other causes include splenic artery thrombosis, sickle cell disease, hematologic disorders, and trauma. Clinical presentation can vary widely, ranging from being asymptomatic to acute abdominal pain, nausea, vomiting, and fever. Diagnosis is often made with imaging studies such as ultrasound or CT scan. Treatment depends on the underlying cause and severity of symptoms, but may include anticoagulation, antibiotics, or surgical intervention in severe cases.
Coronary angiography is a medical procedure that uses X-ray imaging to visualize the coronary arteries, which supply blood to the heart muscle. During the procedure, a thin, flexible catheter is inserted into an artery in the arm or groin and threaded through the blood vessels to the heart. A contrast dye is then injected through the catheter, and X-ray images are taken as the dye flows through the coronary arteries. These images can help doctors diagnose and treat various heart conditions, such as blockages or narrowing of the arteries, that can lead to chest pain or heart attacks. It is also known as coronary arteriography or cardiac catheterization.
An anterior wall myocardial infarction (AMI) is a type of heart attack that occurs when there is a significant reduction or complete blockage of blood flow to the front wall of the heart muscle, also known as the anterior wall of the left ventricle. This reduction or blockage in blood flow is typically caused by a buildup of fatty deposits, called plaques, in the coronary arteries that supply oxygen-rich blood to the heart muscle.
When a plaque ruptures or breaks open, a blood clot forms around it, which can completely block the flow of blood to the heart muscle. This lack of blood flow causes the heart muscle to start to die, leading to a myocardial infarction or heart attack.
An anterior wall myocardial infarction is often associated with more severe symptoms and a higher risk of complications than other types of heart attacks because it affects a larger area of the heart muscle. Symptoms may include chest pain, shortness of breath, nausea, vomiting, sweating, and anxiety.
Immediate medical attention is necessary for an anterior wall myocardial infarction to restore blood flow to the heart muscle as quickly as possible and prevent further damage. Treatment options may include medications, such as clot-busting drugs or blood thinners, as well as procedures such as angioplasty or coronary artery bypass surgery.
"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.
"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.
The brainstem is the lower part of the brain that connects to the spinal cord. It consists of the midbrain, pons, and medulla oblongata. The brainstem controls many vital functions such as heart rate, breathing, and blood pressure. It also serves as a relay center for sensory and motor information between the cerebral cortex and the rest of the body. Additionally, several cranial nerves originate from the brainstem, including those that control eye movements, facial movements, and hearing.
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.
Ventricular remodeling is a structural adaptation process of the heart in response to stress or injury, such as myocardial infarction (heart attack) or pressure overload. This process involves changes in size, shape, and function of the ventricles (the lower chambers of the heart).
In ventricular remodeling, the heart muscle may thicken, enlarge, or become more stiff, leading to alterations in the pumping ability of the heart. These changes can ultimately result in cardiac dysfunction, heart failure, and an increased risk of arrhythmias (irregular heart rhythms).
Ventricular remodeling is often classified into two types:
1. Concentric remodeling: This occurs when the ventricular wall thickens (hypertrophy) without a significant increase in chamber size, leading to a decrease in the cavity volume and an increase in the thickness of the ventricular wall.
2. Eccentric remodeling: This involves an increase in both the ventricular chamber size and wall thickness due to the addition of new muscle cells (hyperplasia) or enlargement of existing muscle cells (hypertrophy). As a result, the overall shape of the ventricle becomes more spherical and less elliptical.
Both types of remodeling can negatively impact heart function and contribute to the development of heart failure. Close monitoring and appropriate treatment are essential for managing ventricular remodeling and preventing further complications.
Myocardial reperfusion is the restoration of blood flow to the heart muscle (myocardium), usually after a period of ischemia or reduced oxygen supply, such as during a myocardial infarction (heart attack). This can be achieved through various medical interventions, including thrombolytic therapy, percutaneous coronary intervention (PCI), or coronary artery bypass surgery (CABG). The goal of myocardial reperfusion is to salvage the jeopardized myocardium, preserve cardiac function, and reduce the risk of complications like heart failure or arrhythmias. However, it's important to note that while reperfusion is crucial for treating ischemic heart disease, it can also lead to additional injury to the heart muscle, known as reperfusion injury.
Brainstem infarctions refer to the damage or death of brain tissue in the brainstem due to lack of blood supply, resulting in a localized injury known as an infarction. The brainstem is a critical region that controls essential functions such as breathing, heart rate, and consciousness. Infarctions in this area can result in various symptoms depending on the location and extent of damage, which may include:
1. Hemiparesis or paralysis on one side of the body
2. Cranial nerve dysfunction, leading to double vision, slurred speech, or facial weakness
3. Difficulty swallowing or speaking
4. Unstable blood pressure and heart rate
5. Altered level of consciousness, ranging from confusion to coma
6. Abnormal muscle tone and reflexes
7. Respiratory disturbances, such as irregular breathing patterns or apnea (cessation of breathing)
Brainstem infarctions can be caused by various conditions, including atherosclerosis, embolism, vasospasm, or small vessel disease. Prompt diagnosis and treatment are crucial to minimize the risk of long-term disability or death.
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.
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.
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 myocardium is the middle layer of the heart wall, composed of specialized cardiac muscle cells that are responsible for pumping blood throughout the body. It forms the thickest part of the heart wall and is divided into two sections: the left ventricle, which pumps oxygenated blood to the rest of the body, and the right ventricle, which pumps deoxygenated blood to the lungs.
The myocardium contains several types of cells, including cardiac muscle fibers, connective tissue, nerves, and blood vessels. The muscle fibers are arranged in a highly organized pattern that allows them to contract in a coordinated manner, generating the force necessary to pump blood through the heart and circulatory system.
Damage to the myocardium can occur due to various factors such as ischemia (reduced blood flow), infection, inflammation, or genetic disorders. This damage can lead to several cardiac conditions, including heart failure, arrhythmias, and cardiomyopathy.
Creatine kinase (CK) is a muscle enzyme that is normally present in small amounts in the blood. It is primarily found in tissues that require a lot of energy, such as the heart, brain, and skeletal muscles. When these tissues are damaged or injured, CK is released into the bloodstream, causing the levels to rise.
Creatine kinase exists in several forms, known as isoenzymes, which can be measured in the blood to help identify the location of tissue damage. The three main isoenzymes are:
1. CK-MM: Found primarily in skeletal muscle
2. CK-MB: Found primarily in heart muscle
3. CK-BB: Found primarily in the brain
Elevated levels of creatine kinase, particularly CK-MB, can indicate damage to the heart muscle, such as occurs with a heart attack. Similarly, elevated levels of CK-BB may suggest brain injury or disease. Overall, measuring creatine kinase levels is a useful diagnostic tool for assessing tissue damage and determining the severity of injuries or illnesses.
Streptokinase is a thrombolytic or clot-busting enzyme produced by certain strains of streptococcus bacteria. It functions by converting plasminogen to plasmin, which then degrades fibrin, a protein that forms the structural framework of blood clots. This activity helps in dissolving blood clots and restoring blood flow in areas obstructed by them. In a medical context, streptokinase is often used as a medication to treat conditions associated with abnormal blood clotting, such as heart attacks, pulmonary embolisms, and deep vein thromboses. However, its use carries the risk of bleeding complications due to excessive fibrinolysis or clot dissolution.
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.
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.
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.
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.
A brain abscess is a localized collection of pus in the brain that is caused by an infection. It can develop as a result of a bacterial, fungal, or parasitic infection that spreads to the brain from another part of the body or from an infection that starts in the brain itself (such as from a head injury or surgery).
The symptoms of a brain abscess may include headache, fever, confusion, seizures, weakness or numbness on one side of the body, and changes in vision, speech, or behavior. Treatment typically involves antibiotics to treat the infection, as well as surgical drainage of the abscess to relieve pressure on the brain.
It is a serious medical condition that requires prompt diagnosis and treatment to prevent potentially life-threatening complications such as brain herniation or permanent neurological damage.
Left ventricular function refers to the ability of the left ventricle (the heart's lower-left chamber) to contract and relax, thereby filling with and ejecting blood. The left ventricle is responsible for pumping oxygenated blood to the rest of the body. Its function is evaluated by measuring several parameters, including:
1. Ejection fraction (EF): This is the percentage of blood that is pumped out of the left ventricle with each heartbeat. A normal ejection fraction ranges from 55% to 70%.
2. Stroke volume (SV): The amount of blood pumped by the left ventricle in one contraction. A typical SV is about 70 mL/beat.
3. Cardiac output (CO): The total volume of blood that the left ventricle pumps per minute, calculated as the product of stroke volume and heart rate. Normal CO ranges from 4 to 8 L/minute.
Assessment of left ventricular function is crucial in diagnosing and monitoring various cardiovascular conditions such as heart failure, coronary artery disease, valvular heart diseases, and cardiomyopathies.
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.
Coronary Care Units (CCUs) are specialized hospital wards that provide intensive care to patients with severe, life-threatening heart conditions. These units are equipped with advanced monitoring and treatment technologies to continuously monitor a patient's cardiac function and provide immediate medical interventions when necessary. Common conditions treated in CCUs include acute myocardial infarction (heart attack), unstable angina, cardiac arrhythmias, and heart failure. The primary goal of a CCU is to stabilize the patient's condition, prevent further complications, and facilitate recovery.
Coronary artery disease, often simply referred to as coronary disease, is a condition in which the blood vessels that supply oxygen-rich blood to the heart become narrowed or blocked due to the buildup of fatty deposits called plaques. This can lead to chest pain (angina), shortness of breath, or in severe cases, a heart attack.
The medical definition of coronary artery disease is:
A condition characterized by the accumulation of atheromatous plaques in the walls of the coronary arteries, leading to decreased blood flow and oxygen supply to the myocardium (heart muscle). This can result in symptoms such as angina pectoris, shortness of breath, or arrhythmias, and may ultimately lead to myocardial infarction (heart attack) or heart failure.
Risk factors for coronary artery disease include age, smoking, high blood pressure, high cholesterol, diabetes, obesity, physical inactivity, and a family history of the condition. Lifestyle changes such as quitting smoking, exercising regularly, eating a healthy diet, and managing stress can help reduce the risk of developing coronary artery disease. Medical treatments may include medications to control blood pressure, cholesterol levels, or irregular heart rhythms, as well as procedures such as angioplasty or bypass surgery to improve blood flow to the heart.
Angina pectoris is a medical term that describes chest pain or discomfort caused by an inadequate supply of oxygen-rich blood to the heart muscle. This condition often occurs due to coronary artery disease, where the coronary arteries become narrowed or blocked by the buildup of cholesterol, fatty deposits, and other substances, known as plaques. These blockages can reduce blood flow to the heart, causing ischemia (lack of oxygen) and leading to angina symptoms.
There are two primary types of angina: stable and unstable. Stable angina is predictable and usually occurs during physical exertion or emotional stress when the heart needs more oxygen-rich blood. The pain typically subsides with rest or after taking prescribed nitroglycerin medication, which helps widen the blood vessels and improve blood flow to the heart.
Unstable angina, on the other hand, is more severe and unpredictable. It can occur at rest, during sleep, or with minimal physical activity and may not be relieved by rest or nitroglycerin. Unstable angina is considered a medical emergency, as it could indicate an imminent heart attack.
Symptoms of angina pectoris include chest pain, pressure, tightness, or heaviness that typically radiates to the left arm, neck, jaw, or back. Shortness of breath, nausea, sweating, and fatigue may also accompany angina symptoms. Immediate medical attention is necessary if you experience chest pain or discomfort, especially if it's new, severe, or persistent, as it could be a sign of a more serious condition like a heart attack.
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.
'Alcohol drinking' refers to the consumption of alcoholic beverages, which contain ethanol (ethyl alcohol) as the active ingredient. Ethanol is a central nervous system depressant that can cause euphoria, disinhibition, and sedation when consumed in small to moderate amounts. However, excessive drinking can lead to alcohol intoxication, with symptoms ranging from slurred speech and impaired coordination to coma and death.
Alcohol is metabolized in the liver by enzymes such as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). The breakdown of ethanol produces acetaldehyde, a toxic compound that can cause damage to various organs in the body. Chronic alcohol drinking can lead to a range of health problems, including liver disease, pancreatitis, cardiovascular disease, neurological disorders, and increased risk of cancer.
Moderate drinking is generally defined as up to one drink per day for women and up to two drinks per day for men, where a standard drink contains about 14 grams (0.6 ounces) of pure alcohol. However, it's important to note that there are no safe levels of alcohol consumption, and any level of drinking carries some risk to health.
The cerebral cortex is the outermost layer of the brain, characterized by its intricate folded structure and wrinkled appearance. It is a region of great importance as it plays a key role in higher cognitive functions such as perception, consciousness, thought, memory, language, and attention. The cerebral cortex is divided into two hemispheres, each containing four lobes: the frontal, parietal, temporal, and occipital lobes. These areas are responsible for different functions, with some regions specializing in sensory processing while others are involved in motor control or associative functions. The cerebral cortex is composed of gray matter, which contains neuronal cell bodies, and is covered by a layer of white matter that consists mainly of myelinated nerve fibers.
Myocardial ischemia is a condition in which the blood supply to the heart muscle (myocardium) is reduced or blocked, leading to insufficient oxygen delivery and potential damage to the heart tissue. This reduction in blood flow typically results from the buildup of fatty deposits, called plaques, in the coronary arteries that supply the heart with oxygen-rich blood. The plaques can rupture or become unstable, causing the formation of blood clots that obstruct the artery and limit blood flow.
Myocardial ischemia may manifest as chest pain (angina pectoris), shortness of breath, fatigue, or irregular heartbeats (arrhythmias). In severe cases, it can lead to myocardial infarction (heart attack) if the oxygen supply is significantly reduced or cut off completely, causing permanent damage or death of the heart muscle. Early diagnosis and treatment of myocardial ischemia are crucial for preventing further complications and improving patient outcomes.
A biological marker, often referred to as a biomarker, is a measurable indicator that reflects the presence or severity of a disease state, or a response to a therapeutic intervention. Biomarkers can be found in various materials such as blood, tissues, or bodily fluids, and they can take many forms, including molecular, histologic, radiographic, or physiological measurements.
In the context of medical research and clinical practice, biomarkers are used for a variety of purposes, such as:
1. Diagnosis: Biomarkers can help diagnose a disease by indicating the presence or absence of a particular condition. For example, prostate-specific antigen (PSA) is a biomarker used to detect prostate cancer.
2. Monitoring: Biomarkers can be used to monitor the progression or regression of a disease over time. For instance, hemoglobin A1c (HbA1c) levels are monitored in diabetes patients to assess long-term blood glucose control.
3. Predicting: Biomarkers can help predict the likelihood of developing a particular disease or the risk of a negative outcome. For example, the presence of certain genetic mutations can indicate an increased risk for breast cancer.
4. Response to treatment: Biomarkers can be used to evaluate the effectiveness of a specific treatment by measuring changes in the biomarker levels before and after the intervention. This is particularly useful in personalized medicine, where treatments are tailored to individual patients based on their unique biomarker profiles.
It's important to note that for a biomarker to be considered clinically valid and useful, it must undergo rigorous validation through well-designed studies, including demonstrating sensitivity, specificity, reproducibility, and clinical relevance.
Unstable angina is a term used in cardiology to describe chest pain or discomfort that occurs suddenly and unexpectedly, often at rest or with minimal physical exertion. It is caused by an insufficient supply of oxygen-rich blood to the heart muscle due to reduced blood flow, typically as a result of partial or complete blockage of the coronary arteries.
Unlike stable angina, which tends to occur predictably during physical activity and can be relieved with rest or nitroglycerin, unstable angina is more severe, unpredictable, and may not respond to traditional treatments. It is considered a medical emergency because it can be a sign of an impending heart attack or other serious cardiac event.
Unstable angina is often treated in the hospital with medications such as nitroglycerin, beta blockers, calcium channel blockers, and antiplatelet agents to improve blood flow to the heart and prevent further complications. In some cases, more invasive treatments such as coronary angioplasty or bypass surgery may be necessary to restore blood flow to the affected areas of the heart.
Echocardiography is a medical procedure that uses sound waves to produce detailed images of the heart's structure, function, and motion. It is a non-invasive test that can help diagnose various heart conditions, such as valve problems, heart muscle damage, blood clots, and congenital heart defects.
During an echocardiogram, a transducer (a device that sends and receives sound waves) is placed on the chest or passed through the esophagus to obtain images of the heart. The sound waves produced by the transducer bounce off the heart structures and return to the transducer, which then converts them into electrical signals that are processed to create images of the heart.
There are several types of echocardiograms, including:
* Transthoracic echocardiography (TTE): This is the most common type of echocardiogram and involves placing the transducer on the chest.
* Transesophageal echocardiography (TEE): This type of echocardiogram involves passing a specialized transducer through the esophagus to obtain images of the heart from a closer proximity.
* Stress echocardiography: This type of echocardiogram is performed during exercise or medication-induced stress to assess how the heart functions under stress.
* Doppler echocardiography: This type of echocardiogram uses sound waves to measure blood flow and velocity in the heart and blood vessels.
Echocardiography is a valuable tool for diagnosing and managing various heart conditions, as it provides detailed information about the structure and function of the heart. It is generally safe, non-invasive, and painless, making it a popular choice for doctors and patients alike.
Neurons, also known as nerve cells or neurocytes, are specialized cells that constitute the basic unit of the nervous system. They are responsible for receiving, processing, and transmitting information and signals within the body. Neurons have three main parts: the dendrites, the cell body (soma), and the axon. The dendrites receive signals from other neurons or sensory receptors, while the axon transmits these signals to other neurons, muscles, or glands. The junction between two neurons is called a synapse, where neurotransmitters are released to transmit the signal across the gap (synaptic cleft) to the next neuron. Neurons vary in size, shape, and structure depending on their function and location within the nervous system.
Brain hypoxia is a medical condition characterized by a reduced supply of oxygen to the brain. The brain requires a continuous supply of oxygen to function properly, and even a brief period of hypoxia can cause significant damage to brain cells.
Hypoxia can result from various conditions, such as cardiac arrest, respiratory failure, carbon monoxide poisoning, or high altitude exposure. When the brain is deprived of oxygen, it can lead to a range of symptoms, including confusion, disorientation, seizures, loss of consciousness, and ultimately, brain death.
Brain hypoxia is a medical emergency that requires immediate treatment to prevent long-term neurological damage or death. Treatment typically involves addressing the underlying cause of hypoxia, such as administering oxygen therapy, resuscitating the heart, or treating respiratory failure. In some cases, more invasive treatments, such as therapeutic hypothermia or mechanical ventilation, may be necessary to prevent further brain damage.
The Blood-Brain Barrier (BBB) is a highly specialized, selective interface between the central nervous system (CNS) and the circulating blood. It is formed by unique endothelial cells that line the brain's capillaries, along with tight junctions, astrocytic foot processes, and pericytes, which together restrict the passage of substances from the bloodstream into the CNS. This barrier serves to protect the brain from harmful agents and maintain a stable environment for proper neural function. However, it also poses a challenge in delivering therapeutics to the CNS, as most large and hydrophilic molecules cannot cross the BBB.
Coronary vessels refer to the network of blood vessels that supply oxygenated blood and nutrients to the heart muscle, also known as the myocardium. The two main coronary arteries are the left main coronary artery and the right coronary artery.
The left main coronary artery branches off into the left anterior descending artery (LAD) and the left circumflex artery (LCx). The LAD supplies blood to the front of the heart, while the LCx supplies blood to the side and back of the heart.
The right coronary artery supplies blood to the right lower part of the heart, including the right atrium and ventricle, as well as the back of the heart.
Coronary vessel disease (CVD) occurs when these vessels become narrowed or blocked due to the buildup of plaque, leading to reduced blood flow to the heart muscle. This can result in chest pain, shortness of breath, or a heart attack.
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.
Myocardial revascularization is a medical term that refers to the restoration of blood flow to the heart muscle (myocardium), typically through a surgical or interventional procedure. This is often performed in patients with coronary artery disease, where the buildup of plaque in the coronary arteries restricts blood flow to the heart muscle, causing symptoms such as chest pain (angina) or shortness of breath, and increasing the risk of a heart attack (myocardial infarction).
There are two main types of myocardial revascularization:
1. Coronary artery bypass grafting (CABG): This is a surgical procedure in which a healthy blood vessel from another part of the body is used to create a detour around the blocked or narrowed coronary artery, allowing blood to flow more freely to the heart muscle.
2. Percutaneous coronary intervention (PCI), also known as angioplasty and stenting: This is a minimally invasive procedure in which a thin catheter is inserted into an artery in the groin or arm and threaded up to the blocked or narrowed coronary artery. A balloon is then inflated to widen the artery, and a stent may be placed to keep it open.
Both procedures aim to improve symptoms, reduce the risk of heart attack, and prolong survival in appropriately selected patients with coronary artery disease.
An Inferior Wall Myocardial Infarction (MI) is a type of heart attack that occurs when there is a significant reduction or complete blockage of blood flow to the inferior (lower) region of the heart muscle, specifically the areas supplied by the right coronary artery or one of its branches. This reduction in blood flow, often caused by a blood clot forming around a ruptured plaque within the artery, can lead to ischemia and ultimately result in damage or death of the heart muscle cells (myocardial necrosis). Symptoms may include chest pain, shortness of breath, sweating, nausea, or vomiting. Diagnosis typically involves an electrocardiogram (ECG) and cardiac biomarker tests, such as troponin levels. Treatment includes medications, lifestyle changes, and possibly interventions like angioplasty or bypass surgery to restore blood flow.
Left ventricular dysfunction (LVD) is a condition characterized by the impaired ability of the left ventricle of the heart to pump blood efficiently during contraction. The left ventricle is one of the four chambers of the heart and is responsible for pumping oxygenated blood to the rest of the body.
LVD can be caused by various underlying conditions, such as coronary artery disease, cardiomyopathy, valvular heart disease, or hypertension. These conditions can lead to structural changes in the left ventricle, including remodeling, hypertrophy, and dilation, which ultimately impair its contractile function.
The severity of LVD is often assessed by measuring the ejection fraction (EF), which is the percentage of blood that is pumped out of the left ventricle during each contraction. A normal EF ranges from 55% to 70%, while an EF below 40% is indicative of LVD.
LVD can lead to various symptoms, such as shortness of breath, fatigue, fluid retention, and decreased exercise tolerance. It can also increase the risk of complications, such as heart failure, arrhythmias, and cardiac arrest. Treatment for LVD typically involves managing the underlying cause, along with medications to improve contractility, reduce fluid buildup, and control heart rate. In severe cases, devices such as implantable cardioverter-defibrillators (ICDs) or left ventricular assist devices (LVADs) may be required.
Coronary circulation refers to the circulation of blood in the coronary vessels, which supply oxygenated blood to the heart muscle (myocardium) and drain deoxygenated blood from it. The coronary circulation system includes two main coronary arteries - the left main coronary artery and the right coronary artery - that branch off from the aorta just above the aortic valve. These arteries further divide into smaller branches, which supply blood to different regions of the heart muscle.
The left main coronary artery divides into two branches: the left anterior descending (LAD) artery and the left circumflex (LCx) artery. The LAD supplies blood to the front and sides of the heart, while the LCx supplies blood to the back and sides of the heart. The right coronary artery supplies blood to the lower part of the heart, including the right ventricle and the bottom portion of the left ventricle.
The veins that drain the heart muscle include the great cardiac vein, the middle cardiac vein, and the small cardiac vein, which merge to form the coronary sinus. The coronary sinus empties into the right atrium, allowing deoxygenated blood to enter the right side of the heart and be pumped to the lungs for oxygenation.
Coronary circulation is essential for maintaining the health and function of the heart muscle, as it provides the necessary oxygen and nutrients required for proper contraction and relaxation of the myocardium. Any disruption or blockage in the coronary circulation system can lead to serious consequences, such as angina, heart attack, or even death.
In medical terms, the heart is a muscular organ located in the thoracic cavity that functions as a pump to circulate blood throughout the body. It's responsible for delivering oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the rest of the body. The heart's rhythmic contractions and relaxations are regulated by a complex electrical conduction system.
Stroke volume is a term used in cardiovascular physiology and medicine. It refers to the amount of blood that is pumped out of the left ventricle of the heart during each contraction (systole). Specifically, it is the difference between the volume of blood in the left ventricle at the end of diastole (when the ventricle is filled with blood) and the volume at the end of systole (when the ventricle has contracted and ejected its contents into the aorta).
Stroke volume is an important measure of heart function, as it reflects the ability of the heart to pump blood effectively to the rest of the body. A low stroke volume may indicate that the heart is not pumping efficiently, while a high stroke volume may suggest that the heart is working too hard. Stroke volume can be affected by various factors, including heart disease, high blood pressure, and physical fitness level.
The formula for calculating stroke volume is:
Stroke Volume = End-Diastolic Volume - End-Systolic Volume
Where end-diastolic volume (EDV) is the volume of blood in the left ventricle at the end of diastole, and end-systolic volume (ESV) is the volume of blood in the left ventricle at the end of systole.
Coronary thrombosis is a medical condition that refers to the formation of a blood clot (thrombus) inside a coronary artery, which supplies oxygenated blood to the heart muscle. The development of a thrombus can partially or completely obstruct blood flow, leading to insufficient oxygen supply to the heart muscle. This can cause chest pain (angina) or a heart attack (myocardial infarction), depending on the severity and duration of the blockage.
Coronary thrombosis often results from the rupture of an atherosclerotic plaque, a buildup of cholesterol, fat, calcium, and other substances in the inner lining (endothelium) of the coronary artery. The ruptured plaque exposes the underlying tissue to the bloodstream, triggering the coagulation cascade and resulting in the formation of a thrombus.
Immediate medical attention is crucial for managing coronary thrombosis, as timely treatment can help restore blood flow, prevent further damage to the heart muscle, and reduce the risk of complications such as heart failure or life-threatening arrhythmias. Treatment options may include medications, such as antiplatelet agents, anticoagulants, and thrombolytic drugs, or interventional procedures like angioplasty and stenting to open the blocked artery. In some cases, surgical intervention, such as coronary artery bypass grafting (CABG), may be necessary.
Percutaneous Coronary Intervention (PCI), also known as coronary angioplasty, is a non-surgical procedure that opens up clogged coronary arteries to improve blood flow to the heart. It involves inserting a thin, flexible catheter into an artery in the groin or wrist and guiding it to the blocked artery in the heart. A small balloon is then inflated to widen the narrowed or blocked artery, and sometimes a stent (a tiny mesh tube) is placed to keep the artery open. This procedure helps to restore and maintain blood flow to the heart muscle, reducing symptoms of angina and improving overall cardiac function.
"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.
Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.
Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.
Hospital mortality is a term used to describe the number or rate of deaths that occur in a hospital setting during a specific period. It is often used as a measure of the quality of healthcare provided by a hospital, as a higher hospital mortality rate may indicate poorer care or more complex cases being treated. However, it's important to note that hospital mortality rates can be influenced by many factors, including the severity of illness of the patients being treated, patient demographics, and the availability of resources and specialized care. Therefore, hospital mortality rates should be interpreted with caution and in the context of other quality metrics.
Cardiogenic shock is a serious condition characterized by the inability of the heart to pump enough blood to meet the body's needs. It is a type of shock that originates from a primary cardiac dysfunction, such as severe heart muscle damage (myocardial infarction or heart attack), abnormal heart rhythms (arrhythmias), or acute valvular insufficiency.
In cardiogenic shock, the low cardiac output leads to inadequate tissue perfusion and oxygenation, resulting in multiple organ dysfunction and failure. Symptoms of cardiogenic shock include severe hypotension (low blood pressure), cool extremities, decreased urine output, altered mental status, and signs of congestive heart failure such as shortness of breath, cough, and peripheral edema.
Cardiogenic shock is a medical emergency that requires prompt diagnosis and immediate treatment, which may include medications to support blood pressure and heart function, mechanical assist devices, or even emergency heart transplantation in some cases.
Coronary artery disease (CAD) is a medical condition in which the coronary arteries, which supply oxygen-rich blood to the heart muscle, become narrowed or blocked due to the buildup of cholesterol, fatty deposits, and other substances, known as plaque. Over time, this buildup can cause the arteries to harden and narrow (a process called atherosclerosis), reducing blood flow to the heart muscle.
The reduction in blood flow can lead to various symptoms and complications, including:
1. Angina (chest pain or discomfort) - This occurs when the heart muscle doesn't receive enough oxygen-rich blood, causing pain, pressure, or discomfort in the chest, arms, neck, jaw, or back.
2. Shortness of breath - When the heart isn't receiving adequate blood flow, it can't pump blood efficiently to meet the body's demands, leading to shortness of breath during physical activities or at rest.
3. Heart attack - If a piece of plaque ruptures or breaks off in a coronary artery, a blood clot can form and block the artery, causing a heart attack (myocardial infarction). This can damage or destroy part of the heart muscle.
4. Heart failure - Chronic reduced blood flow to the heart muscle can weaken it over time, leading to heart failure, a condition in which the heart can't pump blood efficiently to meet the body's needs.
5. Arrhythmias - Reduced blood flow and damage to the heart muscle can lead to abnormal heart rhythms (arrhythmias), which can be life-threatening if not treated promptly.
Coronary artery disease is typically diagnosed through a combination of medical history, physical examination, and diagnostic tests such as electrocardiograms (ECGs), stress testing, cardiac catheterization, and imaging studies like coronary computed tomography angiography (CCTA). Treatment options for CAD include lifestyle modifications, medications, medical procedures, and surgery.
Chronic brain damage is a condition characterized by long-term, persistent injury to the brain that results in cognitive, physical, and behavioral impairments. It can be caused by various factors such as trauma, hypoxia (lack of oxygen), infection, toxic exposure, or degenerative diseases. The effects of chronic brain damage may not be immediately apparent and can worsen over time, leading to significant disability and reduced quality of life.
The symptoms of chronic brain damage can vary widely depending on the severity and location of the injury. They may include:
* Cognitive impairments such as memory loss, difficulty concentrating, trouble with problem-solving and decision-making, and decreased learning ability
* Motor impairments such as weakness, tremors, poor coordination, and balance problems
* Sensory impairments such as hearing or vision loss, numbness, tingling, or altered sense of touch
* Speech and language difficulties such as aphasia (problems with understanding or producing speech) or dysarthria (slurred or slow speech)
* Behavioral changes such as irritability, mood swings, depression, anxiety, and personality changes
Chronic brain damage can be diagnosed through a combination of medical history, physical examination, neurological evaluation, and imaging studies such as MRI or CT scans. Treatment typically focuses on managing symptoms and maximizing function through rehabilitation therapies such as occupational therapy, speech therapy, and physical therapy. In some cases, medication or surgery may be necessary to address specific symptoms or underlying causes of the brain damage.
Heart failure is a pathophysiological state in which the heart is unable to pump sufficient blood to meet the metabolic demands of the body or do so only at the expense of elevated filling pressures. It can be caused by various cardiac disorders, including coronary artery disease, hypertension, valvular heart disease, cardiomyopathy, and arrhythmias. Symptoms may include shortness of breath, fatigue, and fluid retention. Heart failure is often classified based on the ejection fraction (EF), which is the percentage of blood that is pumped out of the left ventricle during each contraction. A reduced EF (less than 40%) is indicative of heart failure with reduced ejection fraction (HFrEF), while a preserved EF (greater than or equal to 50%) is indicative of heart failure with preserved ejection fraction (HFpEF). There is also a category of heart failure with mid-range ejection fraction (HFmrEF) for those with an EF between 40-49%.
Emission-Computed Tomography, Single-Photon (SPECT) is a type of nuclear medicine imaging procedure that generates detailed, three-dimensional images of the distribution of radioactive pharmaceuticals within the body. It uses gamma rays emitted by a radiopharmaceutical that is introduced into the patient's body, and a specialized gamma camera to detect these gamma rays and create tomographic images. The data obtained from the SPECT imaging can be used to diagnose various medical conditions, evaluate organ function, and guide treatment decisions. It is commonly used to image the heart, brain, and bones, among other organs and systems.
Chest pain is a discomfort or pain that you feel in the chest area. The pain can be sharp, dull, burning, crushing, heaviness, or tightness. It may be accompanied by other symptoms such as shortness of breath, sweating, nausea, dizziness, or pain that radiates to the arm, neck, jaw, or back.
Chest pain can have many possible causes, including heart-related conditions such as angina or a heart attack, lung conditions such as pneumonia or pleurisy, gastrointestinal problems such as acid reflux or gastritis, musculoskeletal issues such as costochondritis or muscle strain, and anxiety or panic attacks.
It is important to seek immediate medical attention if you experience chest pain that is severe, persistent, or accompanied by other concerning symptoms, as it may be a sign of a serious medical condition. A healthcare professional can evaluate your symptoms, perform tests, and provide appropriate treatment.
The heart ventricles are the two lower chambers of the heart that receive blood from the atria and pump it to the lungs or the rest of the body. The right ventricle pumps deoxygenated blood to the lungs, while the left ventricle pumps oxygenated blood to the rest of the body. Both ventricles have thick, muscular walls to generate the pressure necessary to pump blood through the circulatory system.
Computer-assisted image processing is a medical term that refers to the use of computer systems and specialized software to improve, analyze, and interpret medical images obtained through various imaging techniques such as X-ray, CT (computed tomography), MRI (magnetic resonance imaging), ultrasound, and others.
The process typically involves several steps, including image acquisition, enhancement, segmentation, restoration, and analysis. Image processing algorithms can be used to enhance the quality of medical images by adjusting contrast, brightness, and sharpness, as well as removing noise and artifacts that may interfere with accurate diagnosis. Segmentation techniques can be used to isolate specific regions or structures of interest within an image, allowing for more detailed analysis.
Computer-assisted image processing has numerous applications in medical imaging, including detection and characterization of lesions, tumors, and other abnormalities; assessment of organ function and morphology; and guidance of interventional procedures such as biopsies and surgeries. By automating and standardizing image analysis tasks, computer-assisted image processing can help to improve diagnostic accuracy, efficiency, and consistency, while reducing the potential for human error.
Tissue Plasminogen Activator (tPA) is a thrombolytic enzyme, which means it dissolves blood clots. It is naturally produced by the endothelial cells that line the interior surface of blood vessels. tPA activates plasminogen, a zymogen, to convert it into plasmin, a protease that breaks down fibrin, the structural protein in blood clots. This enzyme is used medically as a thrombolytic drug under various brand names, such as Activase and Alteplase, to treat conditions like acute ischemic stroke, pulmonary embolism, and deep vein thrombosis by dissolving the clots and restoring blood flow.
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.
Coronary artery bypass surgery, also known as coronary artery bypass grafting (CABG), is a surgical procedure used to improve blood flow to the heart in patients with severe coronary artery disease. This condition occurs when the coronary arteries, which supply oxygen-rich blood to the heart muscle, become narrowed or blocked due to the buildup of fatty deposits, called plaques.
During CABG surgery, a healthy blood vessel from another part of the body is grafted, or attached, to the coronary artery, creating a new pathway for oxygen-rich blood to flow around the blocked or narrowed portion of the artery and reach the heart muscle. This bypass helps to restore normal blood flow and reduce the risk of angina (chest pain), shortness of breath, and other symptoms associated with coronary artery disease.
There are different types of CABG surgery, including traditional on-pump CABG, off-pump CABG, and minimally invasive CABG. The choice of procedure depends on various factors, such as the patient's overall health, the number and location of blocked arteries, and the presence of other medical conditions.
It is important to note that while CABG surgery can significantly improve symptoms and quality of life in patients with severe coronary artery disease, it does not cure the underlying condition. Lifestyle modifications, such as regular exercise, a healthy diet, smoking cessation, and medication therapy, are essential for long-term management and prevention of further progression of the disease.
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.
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.
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.
Analysis of Variance (ANOVA) is a statistical technique used to compare the means of two or more groups and determine whether there are any significant differences between them. It is a way to analyze the variance in a dataset to determine whether the variability between groups is greater than the variability within groups, which can indicate that the groups are significantly different from one another.
ANOVA is based on the concept of partitioning the total variance in a dataset into two components: variance due to differences between group means (also known as "between-group variance") and variance due to differences within each group (also known as "within-group variance"). By comparing these two sources of variance, ANOVA can help researchers determine whether any observed differences between groups are statistically significant, or whether they could have occurred by chance.
ANOVA is a widely used technique in many areas of research, including biology, psychology, engineering, and business. It is often used to compare the means of two or more experimental groups, such as a treatment group and a control group, to determine whether the treatment had a significant effect. ANOVA can also be used to compare the means of different populations or subgroups within a population, to identify any differences that may exist between them.
Hemodynamics is the study of how blood flows through the cardiovascular system, including the heart and the vascular network. It examines various factors that affect blood flow, such as blood volume, viscosity, vessel length and diameter, and pressure differences between different parts of the circulatory system. Hemodynamics also considers the impact of various physiological and pathological conditions on these variables, and how they in turn influence the function of vital organs and systems in the body. It is a critical area of study in fields such as cardiology, anesthesiology, and critical care medicine.
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.
Cardiac arrhythmias are abnormal heart rhythms that result from disturbances in the electrical conduction system of the heart. The heart's normal rhythm is controlled by an electrical signal that originates in the sinoatrial (SA) node, located in the right atrium. This signal travels through the atrioventricular (AV) node and into the ventricles, causing them to contract and pump blood throughout the body.
An arrhythmia occurs when there is a disruption in this electrical pathway or when the heart's natural pacemaker produces an abnormal rhythm. This can cause the heart to beat too fast (tachycardia), too slow (bradycardia), or irregularly.
There are several types of cardiac arrhythmias, including:
1. Atrial fibrillation: A rapid and irregular heartbeat that starts in the atria (the upper chambers of the heart).
2. Atrial flutter: A rapid but regular heartbeat that starts in the atria.
3. Supraventricular tachycardia (SVT): A rapid heartbeat that starts above the ventricles, usually in the atria or AV node.
4. Ventricular tachycardia: A rapid and potentially life-threatening heart rhythm that originates in the ventricles.
5. Ventricular fibrillation: A chaotic and disorganized electrical activity in the ventricles, which can be fatal if not treated immediately.
6. Heart block: A delay or interruption in the conduction of electrical signals from the atria to the ventricles.
Cardiac arrhythmias can cause various symptoms, such as palpitations, dizziness, shortness of breath, chest pain, and fatigue. In some cases, they may not cause any symptoms and go unnoticed. However, if left untreated, certain types of arrhythmias can lead to serious complications, including stroke, heart failure, or even sudden cardiac death.
Treatment for cardiac arrhythmias depends on the type, severity, and underlying causes. Options may include lifestyle changes, medications, cardioversion (electrical shock therapy), catheter ablation, implantable devices such as pacemakers or defibrillators, and surgery. It is essential to consult a healthcare professional for proper evaluation and management of cardiac arrhythmias.
C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.
The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.
C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.
One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.
Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.
Brain Natriuretic Peptide (BNP) is a type of natriuretic peptide that is primarily produced in the heart, particularly in the ventricles. Although it was initially identified in the brain, hence its name, it is now known that the cardiac ventricles are the main source of BNP in the body.
BNP is released into the bloodstream in response to increased stretching or distension of the heart muscle cells due to conditions such as heart failure, hypertension, and myocardial infarction (heart attack). Once released, BNP binds to specific receptors in the kidneys, causing an increase in urine production and excretion of sodium, which helps reduce fluid volume and decrease the workload on the heart.
BNP also acts as a hormone that regulates various physiological functions, including blood pressure, cardiac remodeling, and inflammation. Measuring BNP levels in the blood is a useful diagnostic tool for detecting and monitoring heart failure, as higher levels of BNP are associated with more severe heart dysfunction.
Acute Coronary Syndrome (ACS) is a term used to describe a range of conditions associated with sudden, reduced blood flow to the heart muscle. This reduction in blood flow, commonly caused by blood clots forming in coronary arteries, can lead to damage or death of the heart muscle and is often characterized by symptoms such as chest pain, shortness of breath, and fatigue.
There are three main types of ACS:
1. Unstable Angina: This occurs when there is reduced blood flow to the heart muscle, causing chest pain or discomfort, but the heart muscle is not damaged. It can be a warning sign for a possible future heart attack.
2. Non-ST Segment Elevation Myocardial Infarction (NSTEMI): This type of heart attack occurs when there is reduced blood flow to the heart muscle, causing damage or death of some of the muscle cells. However, the electrical activity of the heart remains relatively normal.
3. ST Segment Elevation Myocardial Infarction (STEMI): This is a serious and life-threatening type of heart attack that occurs when there is a complete blockage in one or more of the coronary arteries, causing extensive damage to the heart muscle. The electrical activity of the heart is significantly altered, which can lead to dangerous heart rhythms and even cardiac arrest.
Immediate medical attention is required for anyone experiencing symptoms of ACS, as prompt treatment can help prevent further damage to the heart muscle and reduce the risk of complications or death. Treatment options may include medications, lifestyle changes, and procedures such as angioplasty or bypass surgery.
Clinical enzyme tests are laboratory tests that measure the amount or activity of certain enzymes in biological samples, such as blood or bodily fluids. These tests are used to help diagnose and monitor various medical conditions, including organ damage, infection, inflammation, and genetic disorders.
Enzymes are proteins that catalyze chemical reactions in the body. Some enzymes are found primarily within specific organs or tissues, so elevated levels of these enzymes in the blood can indicate damage to those organs or tissues. For example, high levels of creatine kinase (CK) may suggest muscle damage, while increased levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) can indicate liver damage.
There are several types of clinical enzyme tests, including:
1. Serum enzyme tests: These measure the level of enzymes in the blood serum, which is the liquid portion of the blood after clotting. Examples include CK, AST, ALT, alkaline phosphatase (ALP), and lactate dehydrogenase (LDH).
2. Urine enzyme tests: These measure the level of enzymes in the urine. An example is N-acetyl-β-D-glucosaminidase (NAG), which can indicate kidney damage.
3. Enzyme immunoassays (EIAs): These use antibodies to detect and quantify specific enzymes or proteins in a sample. They are often used for the diagnosis of infectious diseases, such as HIV or hepatitis.
4. Genetic enzyme tests: These can identify genetic mutations that cause deficiencies in specific enzymes, leading to inherited metabolic disorders like phenylketonuria (PKU) or Gaucher's disease.
It is important to note that the interpretation of clinical enzyme test results should be done by a healthcare professional, taking into account the patient's medical history, symptoms, and other diagnostic tests.
Post-infarction heart rupture is a serious and potentially fatal complication that can occur after a myocardial infarction (heart attack). It is defined as the disruption or tearing of the heart muscle (myocardium) in the area that was damaged by the heart attack. This condition typically occurs within 1 to 7 days following a heart attack, and it's more common in elderly patients and those with large infarctions.
There are three main types of post-infarction heart rupture:
1. Ventricular free wall rupture: This is the most common type, where there is a tear in the left ventricular wall, leading to rapid bleeding into the pericardial sac (the space surrounding the heart). This can cause cardiac tamponade, which is a life-threatening situation characterized by increased pressure in the pericardial sac, compromising cardiac filling and reducing cardiac output.
2. Ventricular septal rupture: In this case, there is a tear in the interventricular septum (the wall separating the left and right ventricles), leading to a communication between the two chambers. This results in a shunt of blood from the high-pressure left ventricle to the low-pressure right ventricle, causing a sudden increase in pulmonary congestion and reduced systemic output.
3. Papillary muscle rupture: The papillary muscles are finger-like projections that attach the heart valves (mitral and tricuspid) to the ventricular walls. Rupture of these muscles can lead to severe mitral or tricuspid regurgitation, causing acute pulmonary edema and reduced cardiac output.
Symptoms of post-infarction heart rupture may include chest pain, shortness of breath, palpitations, hypotension, tachycardia, and signs of cardiogenic shock (such as cold sweats, weak pulse, and altered mental status). Diagnosis is typically made using echocardiography, CT angiography, or MRI. Treatment usually involves emergency surgical intervention to repair the rupture and stabilize the patient's hemodynamic condition.
Medical survival rate is a statistical measure used to determine the percentage of patients who are still alive for a specific period of time after their diagnosis or treatment for a certain condition or disease. It is often expressed as a five-year survival rate, which refers to the proportion of people who are alive five years after their diagnosis. Survival rates can be affected by many factors, including the stage of the disease at diagnosis, the patient's age and overall health, the effectiveness of treatment, and other health conditions that the patient may have. It is important to note that survival rates are statistical estimates and do not necessarily predict an individual patient's prognosis.
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.
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.
Cerebral infarction
Jean-Claude Baron
Carotid artery dissection
Ancrod
Animal model of ischemic stroke
Rose bengal
Eating disorder
Daijiro Kato
David Snowdon
Intracranial pressure
Complications of hypertension
Protectin D1
Hiroyuki Kanno (game designer)
Silent stroke
Migrainous infarction
Infarction
Brain ischemia
List of Suzuka Circuit fatalities
Argyll Robertson pupil
Collicular artery
Alcohol-related dementia
Outline of cardiology
Comorbidity
Deena M. Mistri
Anemic infarct
Identity Crisis (DC Comics)
Apelin receptor
Decompression sickness
Utilization behavior
Intracranial hemorrhage
Ivacaftor therapy post myocardial infarction augments systemic inflammation and evokes contrasting effects with respect to...
Brain, infarction | American Journal of Neuroradiology
Suicidal Ideation Among Patients With Acute Life-Threatening Physical Illness: Patients With Stroke, Traumatic Brain Injury,...
Increasing heart vascularisation after myocardial infarction using brain natriuretic peptide stimulation of endothelial and WT1...
Intracranial Hemorrhage Evaluation With MRI: Practice Essentials, Goals of MRI in the Evaluation of ICH, Pathophysiology
JCDR - Early cerebral infarction, Glasgow coma scale, Magnetic resonance imaging, Traumatic brain injury
Table - Cronobacter sakazakii ST4 Strains and Neonatal Meningitis, United States - Volume 19, Number 1-January 2013 - Emerging...
Clear Stroke Benefit Eludes Embolic Protection: PROTECTED TAVR
Guidelines for Environmental Infection Control in Health-Care Facilities: Recommendations of CDC and the Healthcare Infection...
The epidemiology of silent brain infarction: a systematic review of population-based cohorts | BMC Medicine | Full Text
Advanced Search Results - Public Health Image Library(PHIL)
Reflexology Research For Brain, Paralysis, Stroke, Cerebral Hemorrhage, Cerebral Infarction
Plasma brain natriuretic peptide as an indicator for angiotensin-converting-enzyme inhibition after myocardial infarction -...
Blood glucose, glycosylated haemoglobin, and outcome of ischemic brain infarction. - PDF Download Free
Cerebral infarction - Wikipedia
View of MID-Brain Infarction: Weber's Syndrome with Facial Nerve Palsy: A Case Report
Acute anterior circulation stroke: recanalization using clot angioplasty
Lamotrigine for neuroprotection in secondary progressive multiple sclerosis: a randomised, double-blind, placebo-controlled,...
Fatal outcome after brain stem infarction related to bilateral vertebral artery occlusion - case report of a detrimental...
Aldh2 MGI Mouse Gene Detail - MGI:99600 - aldehyde dehydrogenase 2, mitochondrial
Infarction Patterns in Posterior Cerebral Circulation: Etiology and Prognosis
RealClimate: An Arctic methane worst-case scenario
Concussions and Brain Injuries in Children: United States, 2020 | Blogs | CDC
Enriched Rehabilitative Training Promotes Improved Forelimb Motor Function and Enhanced Dendritic Growth after Focal Ischemic...
BE097667 Marker Search Result - Rat Genome Database
Safety of the Pipeline Embolization Device in Treatment of Posterior Circulation Aneurysms | American Journal of Neuroradiology
A Case of Painless Legs and Moving Toes Syndrome in Parkinson's Disease Responsive to Dopaminergic Therapy
Myocardial infarction4
- In the last decade, similar to myocardial infarction treatment, thrombolytic drugs were introduced in the therapy of cerebral infarction. (wikipedia.org)
- Objective Updated knowledge on the validity of self-reported myocardial infarction (SMI) and self-reported stroke (SRS) is needed in Norway. (bmj.com)
- The SAMINOR 1 questionnaire may also be used to estimate the prevalence of acute myocardial infarction and acute stroke. (bmj.com)
- FDA approves tPA for treatment of acute myocardial infarction, or heart attack. (nih.gov)
Cerebral27
- Purpose We retrospectively evaluated the effect of brain atrophy on the outcome of patients after a large cerebral infarct. (bmj.com)
- We evaluated associations between exposures (fine particulate matter [PM2.5] and residential proximity to major roadways) and measures of total cerebral brain volume, hippocampal volume, white matter hyperintensity volume (log-transformed and extensive white matter hyperintensity volume for age), and covert brain infarcts. (nih.gov)
- RESULTS: A 2-μg/m(3) increase in PM2.5 was associated with -0.32% (95% confidence interval, -0.59 to -0.05) smaller total cerebral brain volume and 1.46 (95% confidence interval, 1.10 to 1.94) higher odds of covert brain infarcts. (nih.gov)
- We report a 45-year-old man who suffered permanent disability from the non reversible effects of cerebral odema and infarctions associated with Valproate overdose which would have been aggravated by Diazepam. (nih.gov)
- Cerebral infarction is the pathologic process that results in an area of necrotic tissue in the brain (cerebral infarct). (wikipedia.org)
- Symptoms of cerebral infarction are determined by the parts of the brain affected. (wikipedia.org)
- Major risk factors for cerebral infarction are generally the same as for atherosclerosis. (wikipedia.org)
- Cerebral infarction is caused by a disruption to blood supply that is severe enough and long enough in duration to result in tissue death. (wikipedia.org)
- In people who die of cerebral infarction, an autopsy of stroke may give a clue about the duration from the infarction onset until the time of death. (wikipedia.org)
- If cerebral infarction is caused by a thrombus occluding blood flow to an artery supplying the brain, definitive therapy is aimed at removing the blockage by breaking the clot down (thrombolysis), or by removing it mechanically (thrombectomy). (wikipedia.org)
- We report a case of 59-year-old woman with multiple myeloma who developed cerebral infarction probably related to cardiac involvement of amyloidosis, and discuss the pathophysiological mechanisms based on kidney biopsy and characteristic echocardiographic and cardiac magnetic resonance imaging features. (pfmjournal.org)
- A) Fluid attenuated inversion recovery brain magnetic resonance imaging shows cerebral infarcts in the right posterior inferior cerebellar artery territory. (pfmjournal.org)
- An ischemic stroke is death of an area of brain tissue (cerebral infarction) resulting from an inadequate supply of blood and oxygen to the brain due to blockage of an artery. (msdmanuals.com)
- Overview of Stroke A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue due to loss of its blood supply (cerebral infarction). (msdmanuals.com)
- Cerebrovascular disease refers to any abnormality in the brain resulting from a pathological process of the cerebral blood vessels, such as thrombosis, embolism, or hemorrhage ( 1 - 3 ). (frontiersin.org)
- Five major paired arteries supply the dog brain, namely, the rostral, middle, and caudal cerebral arteries and the rostral and caudal cerebellar arteries ( 1 , 4 ). (frontiersin.org)
- All but the caudal cerebellar arteries branch from a ring at the base of the brain, called the cerebral arterial circle or the Circle of Willis, which is formed from the paired internal carotid arteries and the basilar artery ( 1 , 4 ). (frontiersin.org)
- The most common brain lesions are atrophy, cerebral infarction and porencephalic cavities. (scirp.org)
- Neuroprotective strategies, including the early use of pharmacologic agents and induced cerebral hypothermia, may help to decrease the deleterious effects of brain ischemia (3) . (ajnr.org)
- Taken together, we propose a therapeutic modality that target cerebrovascular would represent powerful approaches to prevent brain edema following cerebral ischemia. (benthamscience.com)
- The constellation of cerebral hypoxic and ischaemic changes which follows perinatal asphyxia results in increased cerebral blood flow, cerebral oedema and massive cellular necrosis involving the cortex, basal ganglia and brain stem. (ispub.com)
- A variety of imaging modalities, including structural and functional magnetic resonance imaging (MRI) and positron emission tomography (PET) studies of cerebral metabolism, have shown characteristic changes in the brain of patients with Alzheimer disease in prodromal and even presymptomatic states. (medscape.com)
- Neurovascular dysfunction, including blood-brain barrier (BBB) breakdown and cerebral blood flow (CBF) dysregulation and reduction, is increasingly recognized as contributing to Alzheimer disease. (medscape.com)
- In addition, the immediate cause of her death was "thrombosis with thrombocytopenia syndrome," resulting in brain infarction, elevated cerebral pressure and subsequent death from cerebral hemorrhage. (theepochtimes.com)
- Previous studies have shown that intracerebral administration of glial cell line-derived neurotrophic factor (GDNF) reduces ischemia-mediated cerebral infarction. (ncl.edu.tw)
- Diffusion-weighted MRI can rapidly detect acute cerebral ischemic injury as hyperintense signal changes, reflecting a decline in the apparent diffusion coefficient (ADC) of water through brain parenchyma, whereas ADC is elevated in the chronic stage because of increased extracellular water content. (neurology.org)
- Tissue NECROSIS in any area of the brain, including the CEREBRAL HEMISPHERES , the CEREBELLUM , and the BRAIN STEM . (nih.gov)
Ischemia12
- Development of novel and more effective strategies to prevent stroke, protect the brain during ischemia and reperfusion, and facilitate its recovery after stroke hinges on basic and translational preclinical research. (nih.gov)
- In response to ischemia, the brain degenerates by the process of liquefactive necrosis. (wikipedia.org)
- mean age, 2.6 days) with perinatal brain ischemia were evaluated using LSDI (1520/62.5/1 [TR/TE/excitations]) ( b maximum = 750 s/mm 2 ) and T1- and T2-weighted spin-echo (conventional) MR imaging. (ajnr.org)
- The neurologic sequelae of perinatal brain ischemia include seizures, spasticity, behavioral disturbances, and developmental delay. (ajnr.org)
- Therefore, the development and application of neuroimaging techniques sensitive to the very early changes of brain ischemia are desirable. (ajnr.org)
- Recent studies have documented that diffusion-weighted imaging can show areas of infarction in perinatal brain ischemia before abnormalities are apparent on conventional MR images (7, 11, 12) . (ajnr.org)
- This suggests that diffusion imaging may be useful in the early detection of perinatal brain ischemia and likely is to become crucial in the effective and safe use of neuroprotective strategies (7, 11, 12) . (ajnr.org)
- In this study, we describe the evolution of diffusion changes in neonates with suspected perinatal brain ischemia and some potential limitations of early diffusion-weighted imaging. (ajnr.org)
- To evaluate the diffusion changes occurring in neonatal brain ischemia, we used a robust quantitative diffusion technique, line-scan diffusion imaging (LSDI), which has been shown previously to yield high-quality images in neonates, children, and adults without the use of head restraints, cardiac gating, or specialized hardware (13-17) . (ajnr.org)
- We reviewed the clinical records, laboratory results, and neuroimaging studies of 19 term neonates (between 38 and 42 weeks postconceptional age) ( Table 1 ) who were referred for MR imaging within the first 8 days of life to evaluate suspected perinatal brain ischemia. (ajnr.org)
- Of note, inhibition of nitric oxide synthase (NOS) attenuates BBB disruption following brain ischemia. (benthamscience.com)
- Importantly, endoplasmic reticulum stress (ERS) is particularly damaging to ischemic brains and was found to play a role in the pathophysiology of hypoxia/ischemia-induced neuronal death [ 4 ]. (medsci.org)
Hypoxic-ischemic injury1
- Computed tomography scan of the brain revealed extensive hypoxic ischemic injury with extensive infarction and diffuse brain injury. (psychiatrist.com)
Acute5
- Brain CT 12 hours after the onset showed no evidence of intracranial bleeding and brain MRI revealed acute infarcts in the right posterior inferior cerebellar artery (PICA) territories ( Fig. 1A ). (pfmjournal.org)
- Broadly, I envision designing clinical research that furthers the prognostic utility of optical tools in the treatment of acute brain injury. (upenn.edu)
- Magnetic resonance imaging showed punctate areas of acute infarction within posterior circulation and into the watershed region. (acc.org)
- This is a state of acute neurologic dysfunctions resulting from the effects of perinatal asphyxia on the brain tissue. (ispub.com)
- 4-8 Such hyperintense changes reflect in the acute stage a decline of the apparent diffusion coefficient (ADC) of water in ischemic brain tissue, 2,6 which is presumed to be related to intracellular water accumulation (cytotoxic edema), 4-6 decreased extracellular space, 9 or changes in membrane permeability 10 caused by rapid failure of energy metabolism. (neurology.org)
Cortical infarction3
- a more advanced stage of cortical infarction (arrows) is shown, with gliosis and macrophage infiltration. (nih.gov)
- is a later stage of cortical infarction where there is loss of tissue and collapse of the cortical structure, creating a depression at the meningeal surface. (nih.gov)
- depicts the cellular responses in cortical infarction of known 72 hour duration (PB Little, personal observation). (nih.gov)
Atrophy4
- The inter-caudate distance (ICD) was calculated as an indicator of brain atrophy by measuring the hemi-ICD of the intact side and then multiplying by two to account for brain swelling at the infarct site. (bmj.com)
- Conclusions Brain atrophy may have an association with clinical outcome after a large stroke by a trend of saving patients from an MCO but also by interfering with their functional recovery. (bmj.com)
- This study evaluates the effects of physical exercise on cognition, functional status, brain atrophy, blood flow, and cerebrospinal fluid biomarkers of Alzheimer's disease in adults with a mild memory impairment. (nih.gov)
- Brain image reveals hippocampal atrophy, especially on the right side. (medscape.com)
Intracranial1
- 2, 3, 4, 5] ICH is characterized as bleeding into brain tissue, intracranial space, and ventricles and is the second most disabling form of stroke. (medscape.com)
Magnetic6
- It is well understood that silent brain infarction (SBI) discovered incidentally on magnetic resonance imaging (MRI) after TAVR is more common than stroke. (medscape.com)
- We examined the associations between residential long-term exposure to ambient air pollution and markers of brain aging using magnetic resonance imaging. (nih.gov)
- A magnetic resonance imaging (MRI) scan will also be performed to determine brain anatomy. (nih.gov)
- Patients underwent standardized brain magnetic resonance imaging (MRI) at baseline and after 2 years. (nih.gov)
- Herein, we report a patient with multiple myeloma who suffered from embolic infarction associated with cardiac amyloidosis diagnosed based on the kidney biopsy, echocardiographic and cardiac magnetic resonance imaging (MRI) results. (pfmjournal.org)
- Magnetic resonance imaging series of 130 patients with IE demonstrated that 82% of patients had brain lesions (including ischemic and hemorrhagic), but only 12% were symptomatic. (acc.org)
Lesions6
- [ 6 ] Although frequent, there is debate regarding the significance of these asymptomatic brain lesions. (medscape.com)
- In NTP studies, infarcts are diagnosed as necrosis, and the term "malacia" is reserved for gross lesions in the brain. (nih.gov)
- In ischemic brain lesions, the typical morphologic criteria of neuronal necrosis may take more than 24 hours of survival to manifest in hematoxylin and eosin sections. (nih.gov)
- Selective vulnerability of brain regions to the effects of toxic compounds may imitate the lesions of ischemic necrosis and should be differentiated from insults of that type based on compound exposure and clinical history. (nih.gov)
- We aimed to investigate the association of clinically overt and silent brain lesions with cognitive function in atrial fibrillation (AF) patients. (nih.gov)
- 5 The affected vessels are presumed to induce the lesions in deep white matter through chronic hypoperfusion of the white matter and disruption of the blood-brain barrier, leading to chronic leakage of plasma into the white matter. (bmj.com)
Tumor3
- Computed tomography (CT) and MRI scanning will show damaged area in the brain, showing that the symptoms were not caused by a tumor, subdural hematoma or other brain disorder. (wikipedia.org)
- Isensee, F., Kickingereder, P., Wick, W., Bendszus, M. & Maier-Hein, K. H. Brain tumor segmentation and radiomics survival prediction: contribution to the BRATS 2017 challenge. (crossref.org)
- Neuroimaging is widely believed to be generally useful for excluding reversible causes of dementia syndrome such as normal-pressure hydrocephalus, brain tumor, and subdural hematoma, and for excluding other likely causes of dementia such as cerebrovascular disease. (medscape.com)
20231
- Optics and the Brain, Optica Publishing Group Page: BTu3B.2, 2023. (upenn.edu)
Stroke9
- [ 8 ] While there is increasing recognition that 'overt' stroke is a separate entity from 'covert' (or silent) brain injury (similar to how type 1 and type 2 MI are considered), it should likewise be appreciated that 'spontaneous' SBI may be more clinically meaningful than 'procedural' SBI. (medscape.com)
- These four entities predict the extent of the stroke, the area of the brain affected, the underlying cause, and the prognosis. (wikipedia.org)
- Ischemic stroke usually results when an artery to the brain is blocked, often by a blood clot and/or a fatty deposit due to atherosclerosis. (msdmanuals.com)
- An ischemic stroke typically results from blockage of an artery that supplies blood to the brain, most commonly a branch of one of the internal carotid arteries. (msdmanuals.com)
- When the large arteries that supply the brain are blocked, some people have no symptoms or have only a small stroke. (msdmanuals.com)
- When blockages develop slowly and gradually (as occurs in atherosclerosis), new arteries may grow in time to keep the affected area of the brain supplied with blood and thus prevent a stroke. (msdmanuals.com)
- Although in experimental stroke models, 4,5,13,15-18 the hyperacute decrease in the ADC changed to a pseudonormalization or an elevation compared with normal brain tissue, the exact time boundaries of these changes have not been determined for human stroke. (neurology.org)
- A stroke occurs when the blood supply to brain tissue is blocked by a blood clot (ischemic stroke), or when a blood vessel in the brain ruptures (hemorrhagic stroke), causing brain cells to die and leading to functional impairments. (nih.gov)
- When administered quickly after stroke onset (within three hours, as approved by the FDA), tPA helps to restore blood flow to brain regions affected by a stroke, thereby limiting the risk of damage and functional impairment. (nih.gov)
Tissue4
- At 72 hours after infarction, the capillary nuclear hypertrophy (arrow), early macrophage response, and some fragmentation of the affected tissue are evident. (nih.gov)
- Even in cases where there is a complete blockage to blood flow of a major blood vessel supplying the brain, there is typically some blood flow to the downstream tissue through collateral blood vessels, and the tissue can typically survive for some length of time that is dependent upon the level of remaining blood flow. (wikipedia.org)
- [9] Their spectra of symptoms also overlap, although the symptoms from arterial gas embolism are generally more severe because they often arise from an infarction (blockage of blood supply and tissue death). (wikipedia.org)
- 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. (nih.gov)
Cognition1
- The neurobiological effects of physical exercise are numerous and involve a wide range of interrelated effects on brain structure, [1] brain function, and cognition . (wikipedia.org)
Dementia2
- Practice parameters for diagnosis and evaluation of dementia, as published by the American Academy of Neurology (AAN), consider structural brain imaging to be optimal. (medscape.com)
- Frontotemporal dementia (FTD) is a group of degenerative brain disorders causing progressive deterioration in behavior, language, and/or movement. (netce.com)
Occurs4
- If the infarction occurs on the left side brain, speech will be slurred. (wikipedia.org)
- 2 Asymptomatic brain infarction occurs in the majority of patients with IE. (acc.org)
- It most commonly occurs following perinatal asphyxia and causes significant brain damage. (ispub.com)
- Therefore, steps need to be taken to prevent secondary brain damage that occurs in the therapeutic window. (ispub.com)
Transient1
- 5. Frequency of silent brain infarction in transient global amnesia. (nih.gov)
Infarcts3
- BACKGROUND AND PURPOSE: The differentiation of brain infarcts by region is important because their cause and clinical implications may differ. (opinvisindi.is)
- Neuroinflammation is believed to be involved in the pathophysiological mechanisms of silent brain infarcts (SBI). (univaq.it)
- Clinically, overt and silent brain infarcts had a similar impact on cognitive decline. (nih.gov)
Arteries1
- There were 10,779 deaths from Cerebrovascular diseases (including haemorrhages, strokes, infarctions and blocked arteries of the brain) in 2012, making these the second most common cause of death. (abs.gov.au)
Embolic1
- Vascular damage following embolic stoke leads to disruption of BBB, thereby eliciting brain edema. (benthamscience.com)
Occlusion1
- Basilar and right vertebral artery occlusion, which caused a brain stem infarction, occurred in an 11-year-old boy. (nih.gov)
Cognitive2
- BACKGROUND AND PURPOSE: Long-term exposure to ambient air pollution is associated with cerebrovascular disease and cognitive impairment, but whether it is related to structural changes in the brain is not clear. (nih.gov)
- some of these long-term effects include: increased neuron growth , increased neurological activity (e.g., c-Fos and BDNF signaling), improved stress coping, enhanced cognitive control of behavior , improved declarative , spatial , and working memory, and structural and functional improvements in brain structures and pathways associated with cognitive control and memory. (wikipedia.org)
Atherosclerosis1
- The aim of this study was to determine whether there is an association between MPO polymorphisms and brain infarction (BI), one of the main consequences of atherosclerosis. (nih.gov)
Ischemic brain injury3
- Using line-scan diffusion imaging (LSDI), we investigated perinatal ischemic brain injury. (ajnr.org)
- Despite technological improvements in obstetric and perinatal care, ischemic brain injury remains a major cause of infant morbidity and mortality (1-3) . (ajnr.org)
- Diffusion-weighted MRI, which is based on the translational movement or diffusion of water, 1-3 can rapidly detect and localize ischemic brain injury as a hyperintense region. (neurology.org)
Abnormalities1
- The aim of this study was to determine clinical or electroencephalogram variables which could predict brain CT-scan abnormalities in childhood epilepsy. (scirp.org)
Lesion2
- [ 7 ] Interestingly, though CEPD use was associated with lower mean brain lesion volume and total lesion volume on DWI, the number of SBIs did not differ with CEPD use. (medscape.com)
- there is little, if any, evidence of inflammatory infiltrate at the margin of the lesion, indicating that the infarction is less than 24 hours old. (nih.gov)
Occur1
- Pathologic accumulation of blood in the cranial vault (ie, ICH) may occur in the brain parenchyma or in surrounding meningeal spaces. (medscape.com)
Vascular2
- As the focus of this review is to describe established and emerging imaging modalities for characterizing vascular accidents, knowledge of the vascular anatomy of the brain is essential. (frontiersin.org)
- The blood-brain barrier (BBB) in brain microvessels maintains homeostasis of the brain microenvironment mostly through maintenance of tight junctions between brain vascular endothelial cells, thereby preventing passage of hydrophilic molecules or toxic substances from the blood to the brain. (benthamscience.com)
Imaging2
- Diagnosis is usually based on symptoms and results of a physical examination and brain imaging. (msdmanuals.com)
- MR diffusion-weighted imaging provides early demonstration of neonatal brain infarction. (ajnr.org)
Hippocampus1
- MRI can be considered the preferred neuroimaging examination for Alzheimer disease because it allows accurate measurement of the 3-dimensional (3D) volume of brain structures, especially the size of the hippocampus and related regions. (medscape.com)
Mechanisms1
- In this review, we focus on mechanisms of decreased brain infarction by these vasoprotective agents. (benthamscience.com)
Disorders1
- The cause of schizophrenia and its association with brain dopamine receptors is not known but may be clarified by studying dopamine receptors in people who have dopamine disorders (such as schizophrenia) and those who do not. (nih.gov)
Injury1
- Protection of Neurovascular Injury by Vasoprotective Agents: A Novel Therapeutic Strategy for Ischemic Brain Edema, Frontiers in Drug Design and Discovery (2007) 3: 433. (benthamscience.com)