A membrane on the vitreal surface of the retina resulting from the proliferation of one or more of three retinal elements: (1) fibrous astrocytes; (2) fibrocytes; and (3) retinal pigment epithelial cells. Localized epiretinal membranes may occur at the posterior pole of the eye without clinical signs or may cause marked loss of vision as a result of covering, distorting, or detaching the fovea centralis. Epiretinal membranes may cause vascular leakage and secondary retinal edema. In younger individuals some membranes appear to be developmental in origin and occur in otherwise normal eyes. The majority occur in association with retinal holes, ocular concussions, retinal inflammation, or after ocular surgery. (Newell, Ophthalmology: Principles and Concepts, 7th ed, p291)
Removal of the whole or part of the vitreous body in treating endophthalmitis, diabetic retinopathy, retinal detachment, intraocular foreign bodies, and some types of glaucoma.
Vitreoretinal membrane shrinkage or contraction secondary to the proliferation of primarily retinal pigment epithelial cells and glial cells, particularly fibrous astrocytes, followed by membrane formation. The formation of fibrillar collagen and cellular proliferation appear to be the basis for the contractile properties of the epiretinal and vitreous membranes.
Perforations through the whole thickness of the retina including the macula as the result of inflammation, trauma, degeneration, etc. The concept includes retinal breaks, tears, dialyses, and holes.
The transparent, semigelatinous substance that fills the cavity behind the CRYSTALLINE LENS of the EYE and in front of the RETINA. It is contained in a thin hyaloid membrane and forms about four fifths of the optic globe.
Separation of the inner layers of the retina (neural retina) from the pigment epithelium. Retinal detachment occurs more commonly in men than in women, in eyes with degenerative myopia, in aging and in aphakia. It may occur after an uncomplicated cataract extraction, but it is seen more often if vitreous humor has been lost during surgery. (Dorland, 27th ed; Newell, Ophthalmology: Principles and Concepts, 7th ed, p310-12).
Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.
Retinal diseases refer to a diverse group of vision-threatening disorders that affect the retina's structure and function, including age-related macular degeneration, diabetic retinopathy, retinal detachment, retinitis pigmentosa, and macular edema, among others.
Detachment of the corpus vitreum (VITREOUS BODY) from its normal attachments, especially the retina, due to shrinkage from degenerative or inflammatory conditions, trauma, myopia, or senility.
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
An oval area in the retina, 3 to 5 mm in diameter, usually located temporal to the posterior pole of the eye and slightly below the level of the optic disk. It is characterized by the presence of a yellow pigment diffusely permeating the inner layers, contains the fovea centralis in its center, and provides the best phototropic visual acuity. It is devoid of retinal blood vessels, except in its periphery, and receives nourishment from the choriocapillaris of the choroid. (From Cline et al., Dictionary of Visual Science, 4th ed)
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
Diseases affecting the eye.
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
Disease of the RETINA as a complication of DIABETES MELLITUS. It is characterized by the progressive microvascular complications, such as ANEURYSM, interretinal EDEMA, and intraocular PATHOLOGIC NEOVASCULARIZATION.
Surgery performed on the eye or any of its parts.
The layer of pigment-containing epithelial cells in the RETINA; the CILIARY BODY; and the IRIS in the eye.
A diazo-naphthalene sulfonate that is widely used as a stain.
An intermediate filament protein found only in glial cells or cells of glial origin. MW 51,000.
An area approximately 1.5 millimeters in diameter within the macula lutea where the retina thins out greatly because of the oblique shifting of all layers except the pigment epithelium layer. It includes the sloping walls of the fovea (clivus) and contains a few rods in its periphery. In its center (foveola) are the cones most adapted to yield high visual acuity, each cone being connected to only one ganglion cell. (Cline et al., Dictionary of Visual Science, 4th ed)
Artificial device such as an externally-worn camera attached to a stimulator on the RETINA, OPTIC NERVE, or VISUAL CORTEX, intended to restore or amplify vision.
Hemorrhage into the VITREOUS BODY.
A tricarbocyanine dye that is used diagnostically in liver function tests and to determine blood volume and cardiac output.
Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).
Fluid accumulation in the outer layer of the MACULA LUTEA that results from intraocular or systemic insults. It may develop in a diffuse pattern where the macula appears thickened or it may acquire the characteristic petaloid appearance referred to as cystoid macular edema. Although macular edema may be associated with various underlying conditions, it is most commonly seen following intraocular surgery, venous occlusive disease, DIABETIC RETINOPATHY, and posterior segment inflammatory disease. (From Survey of Ophthalmology 2004; 49(5) 470-90)
Visualization of a vascular system after intravenous injection of a fluorescein solution. The images may be photographed or televised. It is used especially in studying the retinal and uveal vasculature.
Organic siloxanes which are polymerized to the oily stage. The oils have low surface tension and density less than 1. They are used in industrial applications and in the treatment of retinal detachment, complicated by proliferative vitreoretinopathy.
A condition in which the ocular image of an object as seen by one eye differs in size and shape from that seen by the other.
A method of stopping internal bleeding or blood flow, or the closure of a wound or body cavity, achieved by applying pressure or introducing an absorbent liquid, gel, or tampon.
Chemicals and substances that impart color including soluble dyes and insoluble pigments. They are used in INKS; PAINTS; and as INDICATORS AND REAGENTS.
A class of fibrous proteins or scleroproteins that represents the principal constituent of EPIDERMIS; HAIR; NAILS; horny tissues, and the organic matrix of tooth ENAMEL. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms a coiled-coil alpha helical structure consisting of TYPE I KERATIN and a TYPE II KERATIN, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure. alpha-Keratins have been classified into at least 20 subtypes. In addition multiple isoforms of subtypes have been found which may be due to GENE DUPLICATION.
Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.
Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
Formation of new blood vessels originating from the retinal veins and extending along the inner (vitreal) surface of the retina.
Methods and procedures for the diagnosis of diseases of the eye or of vision disorders.
Partial or complete opacity on or in the lens or capsule of one or both eyes, impairing vision or causing blindness. The many kinds of cataract are classified by their morphology (size, shape, location) or etiology (cause and time of occurrence). (Dorland, 27th ed)
The blood vessels which supply and drain the RETINA.
The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).
Inflammation of part or all of the uvea, the middle (vascular) tunic of the eye, and commonly involving the other tunics (sclera and cornea, and the retina). (Dorland, 27th ed)
Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.
The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the BLOOD-BRAIN BARRIER and BLOOD-RETINAL BARRIER, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear.
The period following a surgical operation.
The marking of biological material with a dye or other reagent for the purpose of identifying and quantitating components of tissues, cells or their extracts.
An intermediate filament protein found in most differentiating cells, in cells grown in tissue culture, and in certain fully differentiated cells. Its insolubility suggests that it serves a structural function in the cytoplasm. MW 52,000.

Human diabetic neovascular membranes contain high levels of urokinase and metalloproteinase enzymes. (1/172)

PURPOSE: Retinal neovascularization is one of the leading causes of blindness. A crucial event in this process is the remodeling and penetration of the capillary basement membrane by migrating endothelial cells. This process requires proteolysis of basement membrane components by a variety of proteinases. The objective of the present study was to determine the expression of proteinases in human retinal tissues showing active neovascularization. METHODS: Epiretinal neovascular membranes surgically removed from patients with proliferative diabetic retinopathy were analyzed by zymography, and the types and amounts of proteinases present in the tissues were determined. Retinas from nondiabetic donor eyes served as control specimens. RESULTS: Both the high- (54 kDa) and low- (33 kDa) molecular-weight forms of urokinase were present at significantly higher levels in neovascular membranes than in normal retinas. The pro forms of the matrix metalloproteinases (MMP) MMP-2 and MMP-9 were significantly elevated in the neovascular membranes in comparison with levels in normal retinas. In addition, the active forms of these enzymes were present in the membranes, whereas there was no detectable level of the active forms in normal retinas. CONCLUSIONS: Human diabetic neovascular membranes contain high levels of urokinase and MMP. The increased activity of proteinases in the final common pathway of retinal neovascularization indicates that inhibition of these enzymes may be a useful therapeutic target as an alternative approach in the management of proliferative retinopathies.  (+info)

N(epsilon)(carboxymethyl)lysin and the AGE receptor RAGE colocalize in age-related macular degeneration. (2/172)

PURPOSE: To investigate whether glycoxidation products and the receptor for advanced glycation end products (RAGE) are present and colocalize in subfoveal membranes of patients with age-related macular degeneration (ARMD). METHODS: Surgically removed subfoveal fibrovascular membranes from 12 patients, 11 related to ARMD and 1 to an idiopathic membrane, were analyzed for the presence of the glycoxidation product N(epsilon)-(carboxymethyl)lysin (CML), one of the receptors for advanced glycation end products, RAGE, and the activation of NFkB, using immunohistochemistry. RESULTS: CML-like immunoreactivity was found in all ARMD specimens examined adjacent or colocalized with RAGE, but not in the idiopathic membrane. RAGE immunoreactive material was found in CD68-positive cells and in the fibrous matrix. CD68-positive cells and surrounding areas stained for p50, the activated form of NFkB. CONCLUSIONS: These results indicate that glycoxidation products are present in subretinal membranes of patients with ARMD. The concomitant expression of RAGE in these membranes and the finding of activated NFkB is suggestive of an implication of glycoxidation product formation in the pathogenesis of the disease.  (+info)

Epithelial-mesenchymal transition in proliferative vitreoretinopathy: intermediate filament protein expression in retinal pigment epithelial cells. (3/172)

PURPOSE: To improve our understanding of how retinal pigment epithelial (RPE) cells behave in vivo and to establish similarities with dedifferentiation and adaptive events observed in RPE cells cultured under simulated intraocular pathologic conditions. At the same time, to examine the origin of epithelioid-shaped and fibroblast/fusiform-shaped cells in epiretinal membranes (ERM) from proliferative vitreoretinopathy (PVR). METHODS: Cells of ERM were studied by electron-immunocytochemical techniques, using simple, double, and triple immunostaining for cytokeratins (CK), vimentin (Vim), and glial fibrillary acidic protein (GFAP). Ultrastructural morphology analysis was also carried out. Adult human RPE cells were obtained and cultured with normal and pathologic vitreous from proliferative vitreoretinal disorders, subretinal fluid aspirates from retinal detachment, and normal human serum. Their cytoskeleton was fractionated at 7 (early cultures) and 24 (late cultures) days of culture, electrophoresed, immunoblotted for intermediate filament proteins, and quantified by densitometric analysis for each condition. Changes in phenotype characteristics were also evaluated. RESULTS: Epithelioid-shaped and fibroblast/fusiform-shaped cells, resembling RPE cells, expressed CK-Vim-GFAP simultaneously as intermediate filament proteins in their cytoskeleton. RPE cells in culture also expressed CK-Vim-GFAP and changed from an epithelial shape to a migratory fibroblast/fusiform-shaped phenotype in the presence of subretinal fluid aspirates and pathologic vitreous from proliferative intraocular disorders. In simulated cultures of proliferative intraocular disorders, cells decreased or retained their CK7, CK8, and CK18, retained Vim, and increased CK19 and GFAP, while their mesenchymal morphology became clearer over time. CONCLUSIONS: Studies of intermediate filament proteins in vivo suggest that dedifferentiation occurs in RPE cells in ERM. Dedifferentiated RPE cells may be responsible for epithelioid-like and fibroblast/fusiform-like cells. Furthermore, changes in intermediate filament protein levels were observed in RPE cells in simulated cultures of proliferative intraocular disorders. These changes were linked to cells acquiring a mesenchymal migratory, phenotype. Results indicate that the dedifferentiation of RPE cells occurs both in vivo and in vitro and that it can be explained as an epithelial-mesenchymal transition.  (+info)

Perifoveal microcirculation in eyes with epiretinal membranes. (4/172)

BACKGROUND/AIMS: Eyes with epiretinal membranes (ERMs) often have alterations of retinal vessels. The authors studied perifoveal microcirculation in eyes with epiretinal membranes (ERMs) using scanning laser ophthalmoscope (SLO) fluorescein angiography. METHODS: Mean capillary blood flow velocity (CFV) was measured as an index of perifoveal microcirculation by SLO fluorescein angiography in 26 eyes with ERMs (19 eyes with idiopathic epiretinal membranes, seven eyes with epiretinal membranes after retinal detachment surgery) before and 6 months after vitreous surgery, and in 23 healthy control subjects. RESULTS: The mean CFV was significantly reduced in eyes with ERMs compared with healthy controls (p=0.012), and the postoperative mean CFV was significantly increased compared with the preoperative mean CFV (p=0.041). CONCLUSION: Significant changes of capillary blood flow velocity in the perifoveal areas were observed between normal subjects and eyes with epiretinal membranes. This indicates that eyes with ERMs show abnormal haemodynamics in the perifoveal capillaries.  (+info)

Erbium: YAG laser ablation of retinal tissue under perfluorodecaline: determination of laser-tissue interaction in pig eyes. (5/172)

PURPOSE: To evaluate the effect of Er;YAG laser on pig retina using a perfluorodecaline/retina interphase with the goal of precisely determining the extent of retinal tissue ablation. METHODS: Free running (tau = 250 microsec) Er:YAG laser pulses were transmitted through a zirconium fluoride (ZrF4) fiber guarded by quartz rod (d = 1000 microm). Laser pulses were applied to the retinal surface of enucleated pig eyes. Eyes were mounted in a specially designed rotating sample holder. The fiber probe was elevated 1.0 +/- 0.3 mm above the retinal surface with perfluorodecaline serving as transmitting medium. The laser energy was applied in a circular pattern with a radius of 3.0 mm. Radiant exposures were set to 1, 3, 5, and 10 J/cm2. RESULTS: Tissue ablation linearly increased with radiant exposure from 3.2 +/- 3.7 microm at 1 J/cm2 up to 40.9 +/- 12.9 microm at 10 J/cm2. Thermal tissue changes extended 70 +/- 10 microm vertically into the retina and 25 +/- 5 microm horizontally. Distortion of outer photoreceptor segments was noticed when the retina was exposed to radiant exposures of 3 J/cm2 or higher. CONCLUSIONS: The Er:YAG laser in combination with perfluorodecaline produced precise ablation of the pig retina, which suggests the feasibility of this technique for safe ablation of epiretinal membranes.  (+info)

Polymerase chain reaction for detection of Mycobacterium tuberculosis in epiretinal membrane in Eales' disease. (6/172)

PURPOSE: Tuberculous etiology has been suggested in Eales' disease. Because epiretinal membrane (ERM) is formed on the inner surface of the retina in Eales' disease, it could be the most appropriate intraocular specimen for investigation. Therefore, a nested polymerase chain reaction (nPCR), which detects MPB64 gene of Mycobacterium tuberculosis on the archival specimens of ERM of well-documented Eales' and non-Eales' patients, was applied and the results compared. METHODS: nPCR technique was standardized, and the sensitivity and specificity of the primers were determined. nPCR technique was applied to tissue sections obtained from formalin-fixed and paraffin-embedded tissues of ERM from 23 patients with Eales' disease and 27 noninfective and non-Eales' disease patients as controls. RESULTS: nPCR technique was specific for M. tuberculosis genome and sensitive enough to detect 0.25 fg (corresponding to the presence of a single bacillus). Eleven (47.8%) ERM of 23 Eales' disease and 3 (11.1%) of 27 controls were positive for M. tuberculosis genome. The difference between the two groups was statistically significant (P = 0.001), indicating association of this bacterium with Eales' disease. CONCLUSIONS: The demonstration of the presence of M. tuberculosis DNA by nPCR technique in significant number of ERM of Eales' disease compared with the controls further emphasizes the probable role of this bacterium in the pathogenesis of this enigmatic clinical condition.  (+info)

Macrophage migration inhibitory factor levels in the vitreous of patients with proliferative diabetic retinopathy. (7/172)

AIMS: To assess the potential role of macrophage migration inhibitory factor (MIF) in the pathogenesis of proliferative diabetic retinopathy (PDR). METHODS: MIF levels were assayed in the vitreous and paired serum samples of 73 consecutive patients with PDR (32 eyes) and macular hole or idiopathic epiretinal membrane (controls, 41 eyes). An enzyme linked immunosorbent assay technique was used to determine the concentrations of MIF. RESULTS: The median vitreous level of MIF was 11.93 ng/ml (range 4.16-103.85) in the patients with PDR, and 1.79 ng/ml (undetectable-8.93) in the controls. Vitreous levels in eyes with PDR were significantly greater than those in the controls (p<0.0001). Vitreous levels were significantly higher than serum levels in eyes with PDR (p=0.0026). MIF levels were significantly higher in the vitreous of PDR patients with severe fibrous proliferation than in those with slight proliferation (p<0.05). CONCLUSION: The results indicate increased levels of MIF in the vitreous of patients with PDR and a significant association between MIF levels and grades of fibrous proliferation, suggesting the possibility that MIF may play a part in the development of the proliferative phase of PDR.  (+info)

Coexpression of VEGF receptors VEGF-R2 and neuropilin-1 in proliferative diabetic retinopathy. (8/172)

PURPOSE: To elucidate vascular endothelial growth factor (VEGF)-mediated pathogenesis of fibrovascular proliferation in diabetic retinopathy. METHODS: Fibrovascular tissues were obtained at vitrectomy from 22 cases with proliferative diabetic retinopathy. The half-divided tissues were processed for reverse transcription-polymerase chain reaction (RT-PCR) analysis to examine the expression of VEGF isoforms and their receptors. Paraffin sections of the other half were used for immunohistochemistry for CD34, glial fibrillary acidic protein and VEGF, and in situ hybridization for VEGF. RESULTS: RT-PCR analysis demonstrated the expression of VEGF receptors VEGF-R1, VEGF-R2, and neuropilin-1 in 12, 14, and 14 of 22 cases, respectively. Notably, VEGF-R2 and neuropilin-1 were simultaneously expressed in the identical 14 tissues. The isoform VEGF121 was constitutively expressed in all the tissues examined, whereas the expression of VEGF165 was confined to the 7 tissues that also expressed VEGF-R2 and neuropilin-1. The vascular density of fibrovascular tissues evaluated by immunohistochemistry for CD34 was significantly higher in the cases with the expression of VEGF-R2 and neuropilin-1 than in those without their expression (P < 0.01), whereas VEGF-R1 expression had no such relationship with the vascular density. The fibrovascular tissues that expressed VEGF165 together with VEGF-R2 and neuropilin-1 were found in significantly younger patients (P < 0.01). In situ hybridization and immunohistochemical studies demonstrated that glial cells in the fibrovascular tissues express and produce VEGF. CONCLUSIONS: Coexpression of VEGF-R2 and neuropilin-1 is suggested to facilitate fibrovascular proliferation in diabetic retinopathy.  (+info)

An epiretinal membrane, also known as a macular pucker or cellophane maculopathy, is a thin and transparent layer of tissue that forms over the macula (the central part of the retina responsible for sharp, detailed vision) in the eye. This membrane can contract and wrinkle the macula, distorting central vision.

Epiretinal membranes are typically caused by the migration and proliferation of glial cells or other cell types onto the surface of the retina following retinal injury, inflammation, or aging. In some cases, they may be associated with other eye conditions such as diabetic retinopathy, retinal vein occlusion, or age-related macular degeneration.

Mild epiretinal membranes may not require treatment, but if the distortion of vision is significant, a vitrectomy surgery may be recommended to remove the membrane and improve visual acuity.

A vitrectomy is a surgical procedure that involves the removal of some or all of the vitreous humor, which is the clear gel-like substance filling the center of the eye. This surgery is often performed to treat various retinal disorders such as diabetic retinopathy, retinal detachment, macular hole, and vitreous hemorrhage.

During a vitrectomy, the ophthalmologist makes small incisions in the sclera (the white part of the eye) to access the vitreous cavity. The surgeon then uses specialized instruments to remove the cloudy or damaged vitreous and may also repair any damage to the retina or surrounding tissues. Afterward, a clear saline solution is injected into the eye to maintain its shape and help facilitate healing.

In some cases, a gas bubble or silicone oil may be placed in the eye after the vitrectomy to help hold the retina in place while it heals. These substances will gradually be absorbed or removed during follow-up appointments. The body naturally produces a new, clear vitreous to replace the removed material over time.

Vitrectomy is typically performed under local anesthesia and may require hospitalization or outpatient care depending on the individual case. Potential risks and complications include infection, bleeding, cataract formation, retinal detachment, and increased eye pressure. However, with proper care and follow-up, most patients experience improved vision after a successful vitrectomy procedure.

Proliferative vitreoretinopathy (PVR) is a sight-threatening complication that can occur after open-globe eye injuries or retinal reattachment surgery. It is characterized by the abnormal growth and contraction of fibrous tissue on the surface of the retina and/or inside the vitreous cavity, which can cause distortion or detachment of the retina. This process can lead to visual impairment or even blindness if left untreated.

The term "proliferative" refers to the abnormal growth of cells (specifically, fibrous and inflammatory cells) on the retinal surface and within the vitreous cavity. These cells form membranes that can contract and cause traction on the retina, leading to distortion or detachment.

PVR is classified into three stages (A, B, and C) based on the extent of fibrous tissue formation and retinal changes. Stage A is characterized by the presence of cellular proliferation without any visible membranes or retinal changes. In stage B, fibrous membranes are present, but there is no retinal detachment. Finally, stage C involves the development of tractional retinal detachment due to the contraction of fibrous membranes.

Treatment for PVR typically involves additional surgical intervention to remove or release the fibrous tissue and reattach the retina. The prognosis for visual recovery depends on the severity and extent of the PVR, as well as the timing and success of treatment.

A retinal perforation is a full-thickness break or hole in the retina, which is the light-sensitive tissue that lines the inner surface of the eye. This condition can lead to a serious complication called retinal detachment, where the retina separates from the underlying tissue, potentially resulting in vision loss if not promptly treated. Retinal perforations may be caused by trauma, certain eye conditions, or invasive eye procedures. Immediate medical attention is required for retinal perforations to prevent further damage and preserve vision.

The vitreous body, also known simply as the vitreous, is the clear, gel-like substance that fills the space between the lens and the retina in the eye. It is composed mainly of water, but also contains collagen fibers, hyaluronic acid, and other proteins. The vitreous helps to maintain the shape of the eye and provides a transparent medium for light to pass through to reach the retina. With age, the vitreous can become more liquefied and may eventually separate from the retina, leading to symptoms such as floaters or flashes of light.

Retinal detachment is a serious eye condition that occurs when the retina, a thin layer of tissue at the back of the eye responsible for processing light and sending visual signals to the brain, pulls away from its normal position. This can lead to significant vision loss or even blindness if not promptly treated. Retinal detachment can be caused by various factors such as aging, trauma, eye disease, or an inflammatory condition. Symptoms of retinal detachment may include sudden flashes of light, floaters, a shadow in the peripheral vision, or a curtain-like covering over part of the visual field. Immediate medical attention is necessary to prevent further damage and preserve vision.

In medical terms, membranes refer to thin layers of tissue that cover or line various structures in the body. They are composed of connective tissue and epithelial cells, and they can be found lining the outer surface of the body, internal organs, blood vessels, and nerves. There are several types of membranes in the human body, including:

1. Serous Membranes: These membranes line the inside of body cavities and cover the organs contained within them. They produce a lubricating fluid that reduces friction between the organ and the cavity wall. Examples include the pleura (lungs), pericardium (heart), and peritoneum (abdominal cavity).
2. Mucous Membranes: These membranes line the respiratory, gastrointestinal, and genitourinary tracts, as well as the inner surface of the eyelids and the nasal passages. They produce mucus to trap particles, bacteria, and other substances, which helps protect the body from infection.
3. Synovial Membranes: These membranes line the joint cavities and produce synovial fluid, which lubricates the joints and allows for smooth movement.
4. Meninges: These are three layers of membranes that cover and protect the brain and spinal cord. They include the dura mater (outermost layer), arachnoid mater (middle layer), and pia mater (innermost layer).
5. Amniotic Membrane: This is a thin, transparent membrane that surrounds and protects the fetus during pregnancy. It produces amniotic fluid, which provides a cushion for the developing baby and helps regulate its temperature.

Retinal diseases refer to a group of conditions that affect the retina, which is the light-sensitive tissue located at the back of the eye. The retina is responsible for converting light into electrical signals that are sent to the brain and interpreted as visual images. Retinal diseases can cause vision loss or even blindness, depending on their severity and location in the retina.

Some common retinal diseases include:

1. Age-related macular degeneration (AMD): A progressive disease that affects the central part of the retina called the macula, causing blurred or distorted vision.
2. Diabetic retinopathy: A complication of diabetes that can damage the blood vessels in the retina, leading to vision loss.
3. Retinal detachment: A serious condition where the retina becomes separated from its underlying tissue, requiring immediate medical attention.
4. Macular edema: Swelling or thickening of the macula due to fluid accumulation, which can cause blurred vision.
5. Retinitis pigmentosa: A group of inherited eye disorders that affect the retina's ability to respond to light, causing progressive vision loss.
6. Macular hole: A small break in the macula that can cause distorted or blurry vision.
7. Retinal vein occlusion: Blockage of the retinal veins that can lead to bleeding, swelling, and potential vision loss.

Treatment for retinal diseases varies depending on the specific condition and its severity. Some treatments include medication, laser therapy, surgery, or a combination of these options. Regular eye exams are essential for early detection and treatment of retinal diseases.

Vitreous detachment, also known as posterior vitreous detachment (PVD), is a common age-related eye condition characterized by the separation of the vitreous gel from the retina. The vitreous is a clear, gel-like substance that fills the space between the lens and the retina in the eye. As we age, the vitreous may change in consistency, becoming more liquefied, leading to the formation of pockets of liquid within the gel.

In vitreous detachment, the posterior part of the vitreous closest to the retina begins to pull away from the retinal surface due to the shrinkage and liquefaction of the vitreous gel. This separation can cause symptoms such as floaters (spots or strands in the field of vision), flashes of light, or a decrease in vision sharpness. While vitreous detachment is typically not a serious condition on its own, it can sometimes lead to complications like retinal tears or retinal detachment, which require immediate medical attention.

Visual acuity is a measure of the sharpness or clarity of vision. It is usually tested by reading an eye chart from a specific distance, such as 20 feet (6 meters). The standard eye chart used for this purpose is called the Snellen chart, which contains rows of letters that decrease in size as you read down the chart.

Visual acuity is typically expressed as a fraction, with the numerator representing the testing distance and the denominator indicating the smallest line of type that can be read clearly. For example, if a person can read the line on the eye chart that corresponds to a visual acuity of 20/20, it means they have normal vision at 20 feet. If their visual acuity is 20/40, it means they must be as close as 20 feet to see what someone with normal vision can see at 40 feet.

It's important to note that visual acuity is just one aspect of overall vision and does not necessarily reflect other important factors such as peripheral vision, depth perception, color vision, or contrast sensitivity.

The macula lutea, often simply referred to as the macula or fovea centralis, is a part of the eye that is responsible for central vision and color perception. It's located in the center of the retina, the light-sensitive tissue at the back of the eye. The macula contains a high concentration of pigments called xanthophylls, which give it a yellowish color and protect the photoreceptor cells in this area from damage by blue light.

The central part of the macula is called the fovea, which is a small depression that contains only cones, the photoreceptor cells responsible for color vision and high visual acuity. The fovea is surrounded by the parafovea and the perifovea, which contain both cones and rods, the photoreceptor cells responsible for low-light vision and peripheral vision.

Damage to the macula can result in a loss of central vision and color perception, a condition known as age-related macular degeneration (AMD), which is a leading cause of blindness in older adults. Other conditions that can affect the macula include macular edema, macular holes, and macular pucker.

The retina is the innermost, light-sensitive layer of tissue in the eye of many vertebrates and some cephalopods. It receives light that has been focused by the cornea and lens, converts it into neural signals, and sends these to the brain via the optic nerve. The retina contains several types of photoreceptor cells including rods (which handle vision in low light) and cones (which are active in bright light and are capable of color vision).

In medical terms, any pathological changes or diseases affecting the retinal structure and function can lead to visual impairment or blindness. Examples include age-related macular degeneration, diabetic retinopathy, retinal detachment, and retinitis pigmentosa among others.

Eye diseases are a range of conditions that affect the eye or visual system, causing damage to vision and, in some cases, leading to blindness. These diseases can be categorized into various types, including:

1. Refractive errors: These include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia, which affect the way light is focused on the retina and can usually be corrected with glasses or contact lenses.
2. Cataracts: A clouding of the lens inside the eye that leads to blurry vision, glare, and decreased contrast sensitivity. Cataract surgery is the most common treatment for this condition.
3. Glaucoma: A group of diseases characterized by increased pressure in the eye, leading to damage to the optic nerve and potential blindness if left untreated. Treatment includes medications, laser therapy, or surgery.
4. Age-related macular degeneration (AMD): A progressive condition that affects the central part of the retina called the macula, causing blurry vision and, in advanced stages, loss of central vision. Treatment may include anti-VEGF injections, laser therapy, or nutritional supplements.
5. Diabetic retinopathy: A complication of diabetes that affects the blood vessels in the retina, leading to bleeding, leakage, and potential blindness if left untreated. Treatment includes laser therapy, anti-VEGF injections, or surgery.
6. Retinal detachment: A separation of the retina from its underlying tissue, which can lead to vision loss if not treated promptly with surgery.
7. Amblyopia (lazy eye): A condition where one eye does not develop normal vision, often due to a misalignment or refractive error in childhood. Treatment includes correcting the underlying problem and encouraging the use of the weaker eye through patching or other methods.
8. Strabismus (crossed eyes): A misalignment of the eyes that can lead to amblyopia if not treated promptly with surgery, glasses, or other methods.
9. Corneal diseases: Conditions that affect the transparent outer layer of the eye, such as keratoconus, Fuchs' dystrophy, and infectious keratitis, which can lead to vision loss if not treated promptly.
10. Uveitis: Inflammation of the middle layer of the eye, which can cause vision loss if not treated promptly with anti-inflammatory medications or surgery.

Optical coherence tomography (OCT) is a non-invasive imaging technique that uses low-coherence light to capture high-resolution cross-sectional images of biological tissues, particularly the retina and other ocular structures. OCT works by measuring the echo time delay of light scattered back from different depths within the tissue, creating a detailed map of the tissue's structure. This technique is widely used in ophthalmology to diagnose and monitor various eye conditions such as macular degeneration, diabetic retinopathy, and glaucoma.

Diabetic retinopathy is a diabetes complication that affects the eyes. It's caused by damage to the blood vessels of the light-sensitive tissue at the back of the eye (retina).

At first, diabetic retinopathy may cause no symptoms or only mild vision problems. Eventually, it can cause blindness. The condition usually affects both eyes.

There are two main stages of diabetic retinopathy:

1. Early diabetic retinopathy. This is when the blood vessels in the eye start to leak fluid or bleed. You might not notice any changes in your vision at this stage, but it's still important to get treatment because it can prevent the condition from getting worse.
2. Advanced diabetic retinopathy. This is when new, abnormal blood vessels grow on the surface of the retina. These vessels can leak fluid and cause severe vision problems, including blindness.

Diabetic retinopathy can be treated with laser surgery, injections of medication into the eye, or a vitrectomy (a surgical procedure to remove the gel-like substance that fills the center of the eye). It's important to get regular eye exams to detect diabetic retinopathy early and get treatment before it causes serious vision problems.

Ophthalmologic surgical procedures refer to various types of surgeries performed on the eye and its surrounding structures by trained medical professionals called ophthalmologists. These procedures aim to correct or improve vision, diagnose and treat eye diseases or injuries, and enhance the overall health and functionality of the eye. Some common examples of ophthalmologic surgical procedures include:

1. Cataract Surgery: This procedure involves removing a cloudy lens (cataract) from the eye and replacing it with an artificial intraocular lens (IOL).
2. LASIK (Laser-Assisted In Situ Keratomileusis): A type of refractive surgery that uses a laser to reshape the cornea, correcting nearsightedness, farsightedness, and astigmatism.
3. Glaucoma Surgery: Several surgical options are available for treating glaucoma, including laser trabeculoplasty, traditional trabeculectomy, and various drainage device implantations. These procedures aim to reduce intraocular pressure (IOP) and prevent further optic nerve damage.
4. Corneal Transplant: This procedure involves replacing a damaged or diseased cornea with a healthy donor cornea to restore vision and improve the eye's appearance.
5. Vitreoretinal Surgery: These procedures focus on treating issues within the vitreous humor (gel-like substance filling the eye) and the retina, such as retinal detachment, macular holes, or diabetic retinopathy.
6. Strabismus Surgery: This procedure aims to correct misalignment of the eyes (strabismus) by adjusting the muscles responsible for eye movement.
7. Oculoplastic Surgery: These procedures involve reconstructive, cosmetic, and functional surgeries around the eye, such as eyelid repair, removal of tumors, or orbital fracture repairs.
8. Pediatric Ophthalmologic Procedures: Various surgical interventions are performed on children to treat conditions like congenital cataracts, amblyopia (lazy eye), or blocked tear ducts.

These are just a few examples of ophthalmic surgical procedures. The specific treatment plan will depend on the individual's condition and overall health.

The pigment epithelium of the eye, also known as the retinal pigment epithelium (RPE), is a layer of cells located between the photoreceptor cells of the retina and the choroid, which is the vascular layer of the eye. The RPE plays a crucial role in maintaining the health and function of the photoreceptors by providing them with nutrients, removing waste products, and helping to regulate the light that enters the eye.

The RPE cells contain pigment granules that absorb excess light, preventing it from scattering within the eye and improving visual acuity. They also help to create a barrier between the retina and the choroid, which is important for maintaining the proper functioning of the photoreceptors. Additionally, the RPE plays a role in the regeneration of visual pigments in the photoreceptor cells, allowing us to see in different light conditions.

Damage to the RPE can lead to various eye diseases and conditions, including age-related macular degeneration (AMD), which is a leading cause of vision loss in older adults.

Trypan Blue is not a medical condition or disease, but rather a medical stain that is used in various medical and laboratory procedures. Here's the medical definition of Trypan Blue:

Trypan Blue is a sterile, non-toxic dye that is commonly used in medical and research settings for staining and visualizing cells and tissues. It has an affinity for staining dead or damaged cells, making it useful for counting viable cells in a sample, as well as identifying and removing damaged cells during certain surgical procedures.

In ophthalmology, Trypan Blue is used as a surgical aid during cataract surgery to stain the lens capsule, providing better visibility and improving the outcome of the procedure. It may also be used in other types of surgeries to help identify and remove damaged or necrotic tissue.

In research settings, Trypan Blue is often used to distinguish live cells from dead cells in cell culture experiments, as well as for staining various tissues and structures during histological examination.

Glial Fibrillary Acidic Protein (GFAP) is a type of intermediate filament protein that is primarily found in astrocytes, which are a type of star-shaped glial cells in the central nervous system (CNS). These proteins play an essential role in maintaining the structural integrity and stability of astrocytes. They also participate in various cellular processes such as responding to injury, providing support to neurons, and regulating the extracellular environment.

GFAP is often used as a marker for astrocytic activation or reactivity, which can occur in response to CNS injuries, neuroinflammation, or neurodegenerative diseases. Elevated GFAP levels in cerebrospinal fluid (CSF) or blood can indicate astrocyte damage or dysfunction and are associated with several neurological conditions, including traumatic brain injury, stroke, multiple sclerosis, Alzheimer's disease, and Alexander's disease.

The fovea centralis, also known as the macula lutea, is a small pit or depression located in the center of the retina, an light-sensitive tissue at the back of the eye. It is responsible for sharp, detailed vision (central vision) and color perception. The fovea contains only cones, the photoreceptor cells that are responsible for color vision and high visual acuity. It has a higher concentration of cones than any other area in the retina, allowing it to provide the greatest detail and color discrimination. The center of the fovea is called the foveola, which contains the highest density of cones and is avascular, meaning it lacks blood vessels to avoid interfering with the light passing through to the photoreceptor cells.

A visual prosthesis, also known as a retinal implant or bionic eye, is a medical device that aims to restore some functional vision in individuals who have severe visual impairment or blindness due to certain eye conditions such as retinitis pigmentosa or age-related macular degeneration.

The prosthesis works by electrically stimulating the remaining viable nerve cells in the retina, which then transmit the signals to the brain via the optic nerve. The device typically consists of a camera that captures visual information, a processor that converts the images into electrical signals, and an electrode array that is implanted onto the surface of the retina.

The electrical stimulation of the retinal cells creates patterns of light in the individual's visual field, allowing them to perceive shapes, edges, and movements. While the level of visual acuity achieved with current visual prostheses is still limited, they can significantly improve the quality of life for some individuals by enabling them to perform tasks such as recognizing objects, navigating their environment, and identifying facial expressions.

A Vitreous Hemorrhage is a medical condition where there is bleeding into the vitreous cavity of the eye. The vitreous cavity is the space in the eye that is filled with a clear, gel-like substance called the vitreous humor. This substance helps to maintain the shape of the eye and transmit light to the retina.

When a vitreous hemorrhage occurs, blood cells from the bleeding mix with the vitreous humor, causing it to become cloudy or hazy. As a result, vision can become significantly impaired, ranging from mildly blurry to complete loss of vision depending on the severity of the bleed.

Vitreous hemorrhages can occur due to various reasons such as trauma, retinal tears or detachments, diabetic retinopathy, age-related macular degeneration, and other eye conditions that affect the blood vessels in the eye. Treatment for vitreous hemorrhage depends on the underlying cause and may include observation, laser surgery, or vitrectomy (a surgical procedure to remove the vitreous humor and stop the bleeding).

Indocyanine green (ICG) is a sterile, water-soluble, tricarbocyanine dye that is used as a diagnostic agent in medical imaging. It is primarily used in ophthalmology for fluorescein angiography to examine blood flow in the retina and choroid, and in cardiac surgery to assess cardiac output and perfusion. When injected into the body, ICG binds to plasma proteins and fluoresces when exposed to near-infrared light, allowing for visualization of various tissues and structures. It is excreted primarily by the liver and has a half-life of approximately 3-4 minutes in the bloodstream.

Vision disorders refer to a wide range of conditions that affect the visual system and result in various symptoms, such as blurry vision, double vision, distorted vision, impaired depth perception, and difficulty with visual tracking or focusing. These disorders can be categorized into several types, including:

1. Refractive errors: These occur when the shape of the eye prevents light from focusing directly on the retina, resulting in blurry vision. Examples include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia (age-related loss of near vision).
2. Strabismus: Also known as crossed eyes or walleye, strabismus is a misalignment of the eyes where they point in different directions, which can lead to double vision or loss of depth perception.
3. Amblyopia: Often called lazy eye, amblyopia is a condition where one eye has reduced vision due to lack of proper visual development during childhood. It may be caused by strabismus, refractive errors, or other factors that interfere with normal visual development.
4. Accommodative disorders: These involve problems with the focusing ability of the eyes, such as convergence insufficiency (difficulty focusing on close objects) and accommodative dysfunction (inability to maintain clear vision at different distances).
5. Binocular vision disorders: These affect how the eyes work together as a team, leading to issues like poor depth perception, eye strain, and headaches. Examples include convergence insufficiency, divergence excess, and suppression.
6. Ocular motility disorders: These involve problems with eye movement, such as nystagmus (involuntary eye movements), strabismus, or restricted extraocular muscle function.
7. Visual processing disorders: These affect the brain's ability to interpret and make sense of visual information, even when the eyes themselves are healthy. Symptoms may include difficulty with reading, recognizing shapes and objects, and understanding spatial relationships.
8. Low vision: This term refers to significant visual impairment that cannot be fully corrected with glasses, contact lenses, medication, or surgery. It includes conditions like macular degeneration, diabetic retinopathy, glaucoma, and cataracts.
9. Blindness: Complete loss of sight in both eyes, which can be caused by various factors such as injury, disease, or genetic conditions.

Macular edema is a medical condition characterized by the accumulation of fluid in the macula, a small area in the center of the retina responsible for sharp, detailed vision. This buildup of fluid causes the macula to thicken and swell, which can distort central vision and lead to vision loss if not treated promptly. Macular edema is often a complication of other eye conditions such as diabetic retinopathy, age-related macular degeneration, retinal vein occlusion, or uveitis. It's important to note that while macular edema can affect anyone, it is more common in people with certain medical conditions like diabetes.

Fluorescein angiography is a medical diagnostic procedure used in ophthalmology to examine the blood flow in the retina and choroid, which are the inner layers of the eye. This test involves injecting a fluorescent dye, Fluorescein, into a patient's arm vein. As the dye reaches the blood vessels in the eye, a specialized camera takes rapid sequences of photographs to capture the dye's circulation through the retina and choroid.

The images produced by fluorescein angiography can help doctors identify any damage to the blood vessels, leakage, or abnormal growth of new blood vessels. This information is crucial in diagnosing and managing various eye conditions such as age-related macular degeneration, diabetic retinopathy, retinal vein occlusions, and inflammatory eye diseases.

It's important to note that while fluorescein angiography is a valuable diagnostic tool, it does carry some risks, including temporary side effects like nausea, vomiting, or allergic reactions to the dye. In rare cases, severe adverse reactions can occur, so patients should discuss these potential risks with their healthcare provider before undergoing the procedure.

Silicone oils are synthetic, polymerized forms of siloxane, which is a type of silicon-based compound. These oils are known for their stability, durability, and resistance to heat, chemicals, and aging. In the medical field, silicone oils are often used in various medical devices and procedures, such as:

1. Intraocular lenses: Silicone oils can be used as a temporary replacement for the vitreous humor (the gel-like substance that fills the eye) during vitreoretinal surgery, particularly when there is a retinal detachment or other serious eye conditions. The oil helps to reattach the retina and maintain its position until a permanent solution can be found.

2. Breast implants: Silicone oils are used as a filling material for breast implants due to their ability to mimic the feel of natural breast tissue. However, the use of silicone breast implants has been controversial due to concerns about potential health risks, including immune system disorders and cancer.

3. Drug delivery systems: Silicone oils can be used as a component in drug-eluting devices, which are designed to deliver medication slowly and consistently over an extended period. These devices can be used in various medical applications, such as wound healing or the treatment of chronic pain.

4. Medical adhesives: Silicone oils can be incorporated into medical adhesives to improve their flexibility, biocompatibility, and resistance to moisture and heat. These adhesives are often used in the manufacturing of medical devices and for securing bandages or dressings to the skin.

It is important to note that while silicone oils have many medical applications, they can also pose potential risks, such as migration, inflammation, or other complications. Therefore, their use should be carefully considered and monitored by healthcare professionals.

Aniseikonia is a medical term that refers to a condition where there is a significant difference in the size or shape of the images perceived by each eye. This occurs when there is a disproportionate amount of magnification or minification between the two eyes, leading to a mismatch in the visual perception of objects' size and shape.

Aniseikonia can result from various factors, including anisometropia (a significant difference in the refractive power between the two eyes), cataract surgery, corneal irregularities, or retinal diseases. It can cause symptoms such as eyestrain, headaches, and difficulty with depth perception, reading, and overall visual comfort.

Treatment for aniseikonia typically involves correcting the underlying refractive error with prescription lenses, prisms, or contact lenses. In some cases, surgical intervention may be necessary to address any structural issues causing the condition.

Endotamponade is a medical term that refers to the use of an internal tamponade in ophthalmology, specifically in the treatment of certain eye conditions such as retinal detachment or severe ocular trauma.

In this procedure, a gas or liquid material is injected into the vitreous cavity (the space inside the eye between the lens and the retina) to help reattach the retina to the wall of the eye or to control bleeding inside the eye. The tamponading agent presses against the retina, holding it in place and preventing further fluid from accumulating under it, which can help promote healing and prevent further damage.

The choice of tamponade material depends on the specific condition being treated. For example, a gas bubble may be used for retinal detachment, while silicone oil may be used for more complex cases or where a longer-lasting tamponade is required. The gas or liquid is usually injected through a small incision in the eye and may be left in place for several weeks or months, depending on the individual case.

Overall, endotamponade is an important technique in the management of various retinal disorders and can help preserve vision and prevent blindness in certain cases.

Coloring agents, also known as food dyes or color additives, are substances that are added to foods, medications, and cosmetics to improve their appearance by giving them a specific color. These agents can be made from both synthetic and natural sources. They must be approved by regulatory agencies such as the U.S. Food and Drug Administration (FDA) before they can be used in products intended for human consumption.

Coloring agents are used for various reasons, including:

* To replace color lost during food processing or preparation
* To make foods more visually appealing
* To help consumers easily identify certain types of food
* To indicate the flavor of a product (e.g., fruit-flavored candies)

It's important to note that while coloring agents can enhance the appearance of products, they do not affect their taste or nutritional value. Some people may have allergic reactions to certain coloring agents, so it's essential to check product labels if you have any known allergies. Additionally, excessive consumption of some synthetic coloring agents has been linked to health concerns, so moderation is key.

Keratins are a type of fibrous structural proteins that constitute the main component of the integumentary system, which includes the hair, nails, and skin of vertebrates. They are also found in other tissues such as horns, hooves, feathers, and reptilian scales. Keratins are insoluble proteins that provide strength, rigidity, and protection to these structures.

Keratins are classified into two types: soft keratins (Type I) and hard keratins (Type II). Soft keratins are found in the skin and simple epithelial tissues, while hard keratins are present in structures like hair, nails, horns, and hooves.

Keratin proteins have a complex structure consisting of several domains, including an alpha-helical domain, beta-pleated sheet domain, and a non-repetitive domain. These domains provide keratin with its unique properties, such as resistance to heat, chemicals, and mechanical stress.

In summary, keratins are fibrous structural proteins that play a crucial role in providing strength, rigidity, and protection to various tissues in the body.

Membrane lipids are the main component of biological membranes, forming a lipid bilayer in which various cellular processes take place. These lipids include phospholipids, glycolipids, and cholesterol. Phospholipids are the most abundant type, consisting of a hydrophilic head (containing a phosphate group) and two hydrophobic tails (composed of fatty acid chains). Glycolipids contain a sugar group attached to the lipid molecule. Cholesterol helps regulate membrane fluidity and permeability. Together, these lipids create a selectively permeable barrier that separates cells from their environment and organelles within cells.

A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.

Immunoenzyme techniques are a group of laboratory methods used in immunology and clinical chemistry that combine the specificity of antibody-antigen reactions with the sensitivity and amplification capabilities of enzyme reactions. These techniques are primarily used for the detection, quantitation, or identification of various analytes (such as proteins, hormones, drugs, viruses, or bacteria) in biological samples.

In immunoenzyme techniques, an enzyme is linked to an antibody or antigen, creating a conjugate. This conjugate then interacts with the target analyte in the sample, forming an immune complex. The presence and amount of this immune complex can be visualized or measured by detecting the enzymatic activity associated with it.

There are several types of immunoenzyme techniques, including:

1. Enzyme-linked Immunosorbent Assay (ELISA): A widely used method for detecting and quantifying various analytes in a sample. In ELISA, an enzyme is attached to either the capture antibody or the detection antibody. After the immune complex formation, a substrate is added that reacts with the enzyme, producing a colored product that can be measured spectrophotometrically.
2. Immunoblotting (Western blot): A method used for detecting specific proteins in a complex mixture, such as a protein extract from cells or tissues. In this technique, proteins are separated by gel electrophoresis and transferred to a membrane, where they are probed with an enzyme-conjugated antibody directed against the target protein.
3. Immunohistochemistry (IHC): A method used for detecting specific antigens in tissue sections or cells. In IHC, an enzyme-conjugated primary or secondary antibody is applied to the sample, and the presence of the antigen is visualized using a chromogenic substrate that produces a colored product at the site of the antigen-antibody interaction.
4. Immunofluorescence (IF): A method used for detecting specific antigens in cells or tissues by employing fluorophore-conjugated antibodies. The presence of the antigen is visualized using a fluorescence microscope.
5. Enzyme-linked immunosorbent assay (ELISA): A method used for detecting and quantifying specific antigens or antibodies in liquid samples, such as serum or culture supernatants. In ELISA, an enzyme-conjugated detection antibody is added after the immune complex formation, and a substrate is added that reacts with the enzyme to produce a colored product that can be measured spectrophotometrically.

These techniques are widely used in research and diagnostic laboratories for various applications, including protein characterization, disease diagnosis, and monitoring treatment responses.

Intracellular membranes refer to the membrane structures that exist within a eukaryotic cell (excluding bacteria and archaea, which are prokaryotic and do not have intracellular membranes). These membranes compartmentalize the cell, creating distinct organelles or functional regions with specific roles in various cellular processes.

Major types of intracellular membranes include:

1. Nuclear membrane (nuclear envelope): A double-membraned structure that surrounds and protects the genetic material within the nucleus. It consists of an outer and inner membrane, perforated by nuclear pores that regulate the transport of molecules between the nucleus and cytoplasm.
2. Endoplasmic reticulum (ER): An extensive network of interconnected tubules and sacs that serve as a major site for protein folding, modification, and lipid synthesis. The ER has two types: rough ER (with ribosomes on its surface) and smooth ER (without ribosomes).
3. Golgi apparatus/Golgi complex: A series of stacked membrane-bound compartments that process, sort, and modify proteins and lipids before they are transported to their final destinations within the cell or secreted out of the cell.
4. Lysosomes: Membrane-bound organelles containing hydrolytic enzymes for breaking down various biomolecules (proteins, carbohydrates, lipids, and nucleic acids) in the process called autophagy or from outside the cell via endocytosis.
5. Peroxisomes: Single-membrane organelles involved in various metabolic processes, such as fatty acid oxidation and detoxification of harmful substances like hydrogen peroxide.
6. Vacuoles: Membrane-bound compartments that store and transport various molecules, including nutrients, waste products, and enzymes. Plant cells have a large central vacuole for maintaining turgor pressure and storing metabolites.
7. Mitochondria: Double-membraned organelles responsible for generating energy (ATP) through oxidative phosphorylation and other metabolic processes, such as the citric acid cycle and fatty acid synthesis.
8. Chloroplasts: Double-membraned organelles found in plant cells that convert light energy into chemical energy during photosynthesis, producing oxygen and organic compounds (glucose) from carbon dioxide and water.
9. Endoplasmic reticulum (ER): A network of interconnected membrane-bound tubules involved in protein folding, modification, and transport; it is divided into two types: rough ER (with ribosomes on the surface) and smooth ER (without ribosomes).
10. Nucleus: Double-membraned organelle containing genetic material (DNA) and associated proteins involved in replication, transcription, RNA processing, and DNA repair. The nuclear membrane separates the nucleoplasm from the cytoplasm and contains nuclear pores for transporting molecules between the two compartments.

Retinal neovascularization is a medical condition characterized by the growth of new, abnormal blood vessels on the surface of the retina, which is the light-sensitive tissue located at the back of the eye. This condition typically occurs in response to an insufficient supply of oxygen and nutrients to the retina, often due to damage or disease, such as diabetic retinopathy or retinal vein occlusion.

The new blood vessels that form during neovascularization are fragile and prone to leakage, which can cause fluid and protein to accumulate in the retina, leading to distorted vision, hemorrhages, and potentially blindness if left untreated. Retinal neovascularization is a serious eye condition that requires prompt medical attention and management to prevent further vision loss.

Diagnostic techniques in ophthalmology refer to the various methods and tests used by eye specialists (ophthalmologists) to examine, evaluate, and diagnose conditions related to the eyes and visual system. Here are some commonly used diagnostic techniques:

1. Visual Acuity Testing: This is a basic test to measure the sharpness of a person's vision. It typically involves reading letters or numbers from an eye chart at a specific distance.
2. Refraction Test: This test helps determine the correct lens prescription for glasses or contact lenses by measuring how light is bent as it passes through the cornea and lens.
3. Slit Lamp Examination: A slit lamp is a microscope that allows an ophthalmologist to examine the structures of the eye, including the cornea, iris, lens, and retina, in great detail.
4. Tonometry: This test measures the pressure inside the eye (intraocular pressure) to detect conditions like glaucoma. Common methods include applanation tonometry and non-contact tonometry.
5. Retinal Imaging: Several techniques are used to capture images of the retina, including fundus photography, fluorescein angiography, and optical coherence tomography (OCT). These tests help diagnose conditions like macular degeneration, diabetic retinopathy, and retinal detachments.
6. Color Vision Testing: This test evaluates a person's ability to distinguish between different colors, which can help detect color vision deficiencies or neurological disorders affecting the visual pathway.
7. Visual Field Testing: This test measures a person's peripheral (or side) vision and can help diagnose conditions like glaucoma, optic nerve damage, or brain injuries.
8. Pupillary Reactions Tests: These tests evaluate how the pupils respond to light and near objects, which can provide information about the condition of the eye's internal structures and the nervous system.
9. Ocular Motility Testing: This test assesses eye movements and alignment, helping diagnose conditions like strabismus (crossed eyes) or nystagmus (involuntary eye movement).
10. Corneal Topography: This non-invasive imaging technique maps the curvature of the cornea, which can help detect irregularities, assess the fit of contact lenses, and plan refractive surgery procedures.

A cataract is a clouding of the natural lens in the eye that affects vision. This clouding can cause vision to become blurry, faded, or dim, making it difficult to see clearly. Cataracts are a common age-related condition, but they can also be caused by injury, disease, or medication use. In most cases, cataracts develop gradually over time and can be treated with surgery to remove the cloudy lens and replace it with an artificial one.

Retinal vessels refer to the blood vessels that are located in the retina, which is the light-sensitive tissue that lines the inner surface of the eye. The retina contains two types of blood vessels: arteries and veins.

The central retinal artery supplies oxygenated blood to the inner layers of the retina, while the central retinal vein drains deoxygenated blood from the retina. These vessels can be visualized during a routine eye examination using an ophthalmoscope, which allows healthcare professionals to assess their health and any potential abnormalities.

Retinal vessels are essential for maintaining the health and function of the retina, and any damage or changes to these vessels can affect vision and lead to various eye conditions such as diabetic retinopathy, retinal vein occlusion, and hypertensive retinopathy.

Membrane potential is the electrical potential difference across a cell membrane, typically for excitable cells such as nerve and muscle cells. It is the difference in electric charge between the inside and outside of a cell, created by the selective permeability of the cell membrane to different ions. The resting membrane potential of a typical animal cell is around -70 mV, with the interior being negative relative to the exterior. This potential is generated and maintained by the active transport of ions across the membrane, primarily through the action of the sodium-potassium pump. Membrane potentials play a crucial role in many physiological processes, including the transmission of nerve impulses and the contraction of muscle cells.

Uveitis is the inflammation of the uvea, the middle layer of the eye between the retina and the white of the eye (sclera). The uvea consists of the iris, ciliary body, and choroid. Uveitis can cause redness, pain, and vision loss. It can be caused by various systemic diseases, infections, or trauma. Depending on the part of the uvea that's affected, uveitis can be classified as anterior (iritis), intermediate (cyclitis), posterior (choroiditis), or pan-uveitis (affecting all layers). Treatment typically includes corticosteroids and other immunosuppressive drugs to control inflammation.

Artificial membranes are synthetic or man-made materials that possess properties similar to natural biological membranes, such as selective permeability and barrier functions. These membranes can be designed to control the movement of molecules, ions, or cells across them, making them useful in various medical and biotechnological applications.

Examples of artificial membranes include:

1. Dialysis membranes: Used in hemodialysis for patients with renal failure, these semi-permeable membranes filter waste products and excess fluids from the blood while retaining essential proteins and cells.
2. Hemofiltration membranes: Utilized in extracorporeal circuits to remove larger molecules, such as cytokines or inflammatory mediators, from the blood during critical illnesses or sepsis.
3. Drug delivery systems: Artificial membranes can be used to encapsulate drugs, allowing for controlled release and targeted drug delivery in specific tissues or cells.
4. Tissue engineering: Synthetic membranes serve as scaffolds for cell growth and tissue regeneration, guiding the formation of new functional tissues.
5. Biosensors: Artificial membranes can be integrated into biosensing devices to selectively detect and quantify biomolecules, such as proteins or nucleic acids, in diagnostic applications.
6. Microfluidics: Artificial membranes are used in microfluidic systems for lab-on-a-chip applications, enabling the manipulation and analysis of small volumes of fluids for various medical and biological purposes.

Neuroglia, also known as glial cells or simply glia, are non-neuronal cells that provide support and protection for neurons in the nervous system. They maintain homeostasis, form myelin sheaths around nerve fibers, and provide structural support. They also play a role in the immune response of the central nervous system. Some types of neuroglia include astrocytes, oligodendrocytes, microglia, and ependymal cells.

The postoperative period is the time following a surgical procedure during which the patient's response to the surgery and anesthesia is monitored, and any complications or adverse effects are managed. This period can vary in length depending on the type of surgery and the individual patient's needs, but it typically includes the immediate recovery phase in the post-anesthesia care unit (PACU) or recovery room, as well as any additional time spent in the hospital for monitoring and management of pain, wound healing, and other aspects of postoperative care.

The goals of postoperative care are to ensure the patient's safety and comfort, promote optimal healing and rehabilitation, and minimize the risk of complications such as infection, bleeding, or other postoperative issues. The specific interventions and treatments provided during this period will depend on a variety of factors, including the type and extent of surgery performed, the patient's overall health and medical history, and any individualized care plans developed in consultation with the patient and their healthcare team.

'Staining and labeling' are techniques commonly used in pathology, histology, cytology, and molecular biology to highlight or identify specific components or structures within tissues, cells, or molecules. These methods enable researchers and medical professionals to visualize and analyze the distribution, localization, and interaction of biological entities, contributing to a better understanding of diseases, cellular processes, and potential therapeutic targets.

Medical definitions for 'staining' and 'labeling' are as follows:

1. Staining: A process that involves applying dyes or stains to tissues, cells, or molecules to enhance their contrast and reveal specific structures or components. Stains can be categorized into basic stains (which highlight acidic structures) and acidic stains (which highlight basic structures). Common staining techniques include Hematoxylin and Eosin (H&E), which differentiates cell nuclei from the surrounding cytoplasm and extracellular matrix; special stains, such as PAS (Periodic Acid-Schiff) for carbohydrates or Masson's trichrome for collagen fibers; and immunostains, which use antibodies to target specific proteins.
2. Labeling: A process that involves attaching a detectable marker or tag to a molecule of interest, allowing its identification, quantification, or tracking within a biological system. Labels can be direct, where the marker is directly conjugated to the targeting molecule, or indirect, where an intermediate linker molecule is used to attach the label to the target. Common labeling techniques include fluorescent labels (such as FITC, TRITC, or Alexa Fluor), enzymatic labels (such as horseradish peroxidase or alkaline phosphatase), and radioactive labels (such as ³²P or ¹⁴C). Labeling is often used in conjunction with staining techniques to enhance the specificity and sensitivity of detection.

Together, staining and labeling provide valuable tools for medical research, diagnostics, and therapeutic development, offering insights into cellular and molecular processes that underlie health and disease.

Vimentin is a type III intermediate filament protein that is expressed in various cell types, including mesenchymal cells, endothelial cells, and hematopoietic cells. It plays a crucial role in maintaining cell structure and integrity by forming part of the cytoskeleton. Vimentin is also involved in various cellular processes such as cell division, motility, and intracellular transport.

In addition to its structural functions, vimentin has been identified as a marker for epithelial-mesenchymal transition (EMT), a process that occurs during embryonic development and cancer metastasis. During EMT, epithelial cells lose their polarity and cell-cell adhesion properties and acquire mesenchymal characteristics, including increased migratory capacity and invasiveness. Vimentin expression is upregulated during EMT, making it a potential target for therapeutic intervention in cancer.

In diagnostic pathology, vimentin immunostaining is used to identify mesenchymal cells and to distinguish them from epithelial cells. It can also be used to diagnose certain types of sarcomas and carcinomas that express vimentin.

For milder cases, nutritional supplements can reduce epiretinal membrane. For severe epiretinal membrane, surgery may be ... Epiretinal membrane or macular pucker is a disease of the eye in response to changes in the vitreous humor or more rarely, ... However, since epiretinal membrane appears to be a protective response to PVD, where inflammation, exudative fluid, and scar ... Epiretinal membrane is typically diagnosed by appearance with optical coherence tomography (OCT) of the macula. Features ...
... epiretinal membrane; tractional macular oedema; myopic macular retinoschisis; visual impairment; blindness. The incidence of ... in idiopathic epimacular membrane. Careful eye examination by an ophthalmologist or optometrist is critical for diagnosing ... or it may induce development of fibrovascular membranes. As with any invasive surgical procedure, PPV introduces trauma to the ... prevents the development of fibrovascular membranes, is less traumatic to the vitreous, and is potentially prophylactic. As of ...
Also called epiretinal membrane. After vitrectomy to remove the vitreous gel, membranectomy is undertaken to peel away the ... If the patient has an epiretinal membrane and is also complaining of symptoms such as decreased visual acuity, then a ... "Epiretinal Membrane". American Academy of Ophthalmology. Retrieved 3 December 2019. "16". Surgical Technology for the Surgical ... This layer of unhealthy tissue is called an epiretinal membrane and it can occur in anyone, but is more likely to occur in the ...
COX-2 expression was found in human idiopathic epiretinal membranes. Cyclooxygenases blocking by lornoxicam in acute stage of ... PTGS (COX, which can be confused with "cytochrome oxidase") enzymes are monotopic membrane proteins; the membrane-binding ... "Cyclo-Oxygenase-2 Expression in Human Idiopathic Epiretinal Membrane". Retina. 30 (5): 719-723. doi:10.1097/iae. ... Picot D, Loll PJ, Garavito RM (January 1994). "The X-ray crystal structure of the membrane protein prostaglandin H2 synthase-1 ...
The ECM laid on the vitreous side of the retina are referred to as epiretinal or preretinal membranes (ERM) and those laid down ... COX-2 expression was found in human idiopathic epiretinal membranes. Phospholipase A2 and cyclooxygenase blocking reduced ... The RPE cells lay down fibrotic membranes while they migrate and these membranes contract and pull at the retina. All these ... The retina can be reattached even with the membrane in place. The other type forms as very thick contractile membranes which ...
Vitreous membrane Central serous retinopathy Epiretinal membrane Vitrectomy Floater Gauger E; Chin EK; Sohn EH (17 November ... The vitreous membrane is more firmly attached to the retina anteriorly, at a structure called the vitreous base. The membrane ... such as epiretinal membrane.[citation needed] PVD may also occur in cases of cataract surgery, within weeks or months of the ... these can allow glial cells to enter the vitreous humor and proliferate to create a thin epiretinal membrane that distorts ...
"Hypotony maculopathy and photoreceptor folds with disruptions after vitrectomy for epiretinal membrane removal: two case ...
... of macular choroidal thickness with optical coherent tomography morphology in patients with idiopathic epiretinal membrane". ...
... is an American ophthalmologist specialized in diabetic retinopathy, epiretinal membranes, and macular ...
Epiretinal membranes (ERM) can also be found on patients where the disease has progressed along to retinal detachment, Rubeosis ... Through examination of samples taken from epiretinal membrane (ERM), genetic similarities with the bacteria have been found. ...
... endothelial growth factor and fibroblast growth factor 5 are colocalized in vascular and avascular epiretinal membranes". ... "Expression of FGF5 in choroidal neovascular membranes associated with ARMD". Current Eye Research. 16 (4): 396-9. doi:10.1076/ ...
Epiretinal membrane Macular degeneration Preferential hyperacuity perimetry Scotoma amslergrid.org "Amsler Grid" Test Free ... Macular pucker: Macular pucker also known as an epiretinal membrane cause metamorphopsia and distortions in central field of ... Epiretinal membrane), as well as the optic nerve and the visual pathway to the brain. Amsler grid usually help detecting ... Chance of metamorphopsia is more in wet AMD compared to dry form.[medical citation needed] Choroidal neovascular membranes: ...
... is employed occasionally for longstanding vitreous hemorrhage and other serious complications such as epiretinal membrane and ... an incision is made in the adventitial sheath adjacent to the arteriovenous crossing and is extended along the membrane that ...
... epiretinal membrane and choroidal neovascularization. Clinical signs include redness of the eye, pain, blurring of vision, ...
He was also the first to use trypan blue for staining epiretinal membranes and publishing the details in his 4 volume textbook ...
For people who have conditions such as Epiretinal membrane (ERM), Macular Holes and Retinal Detachment, decreased ... Some of these conditions include the following: Age-related macular degeneration Epiretinal membrane and vitreomacular traction ...
... epiretinal membranes, macular holes and the various forms of retinal detachment. Scleral buckle was a previously popular ...
Epiretinal membrane - a transparent layer forms and tightens over the retina (H35.4) Peripheral retinal degeneration (H35.5) ...
Handbook of Ocular Disease Management: Epiretinal membrane Archived 2008-04-28 at the Wayback Machine Retrieved on 2008-05-14 ( ... Cellophane Maculopathy A fine glistening membrane forms over the macula, obscuring the vision. EFEMP1 - a gene thought to be ...
... a village ERM protein family Effects range median Emotion-in-relationships model Epiretinal membrane Epithelial cell rests of ...
Contraindications include a history of cystic macular edema (CME), epiretinal membrane formation, vitreous loss during cataract ...
... a 1995 album by British band Selector Macular pucker or epiretinal membrane, an ocular disease Pucker (album), a 2013 album by ...
... and subtle characteristics such as nerve fibre layer defects and epiretinal membranes. This is a method of better observing ... Fundus photography provides a bird's-eye view of the top most layer, the inner limiting membrane, as well as the other ...
... as may be the case with an epiretinal membrane or retinal detachment, the aniseikonia cannot fully be corrected with ...
... epiretinal membrane MeSH C11.768.400 - retinal artery occlusion MeSH C11.768.585 - retinal degeneration MeSH C11.768.585.439 - ...
A third epiretinal device, EPI-RET, has been developed and progressed to clinical testing in six patients. The EPI-RET device ... Additionally, photoreceptor loss can result in the formation of a membrane at the boundary of the damaged photoreceptors, which ... The epiretinal device is known as the Retina Implant and was originally developed in Germany by Retina Implant AG. It completed ... Epiretinal implants are placed in the internal surface of the retina, while subretinal implants are placed between the outer ...
He received his doctorate at the Institute of Biochemistry of the University of Essen on the isolation of basal lamina membrane ... In 1997, his research group demonstrated the feasibility of electronic epiretinal stimulation of retinal cells by implanted ...
The surgeon removes the vitreous humor and any membranes on the retina where the implant will be placed. The implant is ... "IPG519: Interventional procedure overview of insertion of an epiretinal prosthesis for retinitis pigmentosa". National ...
For milder cases, nutritional supplements can reduce epiretinal membrane. For severe epiretinal membrane, surgery may be ... Epiretinal membrane or macular pucker is a disease of the eye in response to changes in the vitreous humor or more rarely, ... However, since epiretinal membrane appears to be a protective response to PVD, where inflammation, exudative fluid, and scar ... Epiretinal membrane is typically diagnosed by appearance with optical coherence tomography (OCT) of the macula. Features ...
These membranes have contractile properties and can lead to visual changes and metamorphopsia because of their effect on the ... Epimacular membranes (EMMs) are collections of collagenous cells that occur on the inner surface of the central retina. ... encoded search term (Epiretinal Membrane) and Epiretinal Membrane What to Read Next on Medscape ... Epiretinal membranes are avascular, fibrocellular membranes that proliferate on the surface of the retina and can lead to ...
Epiretinal Membrane. Author(s): *Retina Department, OftalmoSalud, Arequipa, Av Mariscal Benavides No 307, Urb Selva Alegre, ... Epiretinal Membrane, Ophthalmology: Current and Future Developments Diagnostic Atlas of Retinal Diseases (2016) 1: 227. https ...
... BMJ Open ... Objective: This study was to aggregate the prevalence and risks of epiretinal membranes (ERMs) and determine the possible ...
Optical coherence tomography in the preoperative and postoperative management of macular hole and epiretinal membrane ... Optical coherence tomography in the preoperative and postoperative management of macular hole and epiretinal membrane ...
... in patients with preoperative low vision who had previously removed epiretinal membrane (ERM) with pars plana vitrectomy, and ... Removal of epimacular membranes. Ophthalmol. 1985;92(8):1075-83.. *Grewing R, Mester U. Results of surgery for epiretinal ... Mann-Whitney U test, significance level is p , 0.05, BCVA: best corrected visual acuity, ERM: epiretinal membrane, CG: control ... Okamoto F, Okamoto Y, Hiraoka T, Oshika T. Effect of vitrectomy for epiretinal membrane on visual function and vision-related ...
Epiretinal Membrane - Etiology, pathophysiology, symptoms, signs, diagnosis & prognosis from the MSD Manuals - Medical ... Epiretinal membrane is formation of a thin, fibrotic membrane over the retina that contracts, wrinkling the underlying retina ... Epiretinal Membrane (Macular Pucker; Cellophane Maculopathy; Premacular Fibrosis). By Sonia Mehta , MD, Vitreoretinal Diseases ... Epiretinal membrane typically occurs after age 50 and is most common among people > 75. ...
A rare case with developing and spontaneous separation of Epiretinal Membrane (ERM) during the treatment of Branch Retinal Vein ... Spontaneous separation of epiretinal membrane secondary to branch retinal vein occlusion after a series of intravitreal ... A rare case with developing and spontaneous separation of Epiretinal Membrane (ERM) during the treatment of Branch Retinal Vein ... Keywords: Epiretinal membrane, Posterior vitreous detachment, Branch retinal vein occlusion, Antivascular endothelial growth ...
An epiretinal membrane occurs when the gel-like vitreous in the eye becomes more liquid and exerts an abnormal pull on the ... Epiretinal Membrane (Macular Pucker) - Causes and Risk Factors What causes epiretinal membranes?. When we are young, the ... Epiretinal Membrane. Optical coherence tomography (OCT) scan showing an epiretinal membrane causing distortion of the macula. ... Home , Patient Care , Conditions and Treatment , Epiretinal Membrane (Macular Pucker) , Causes and Risk Factors ...
This membrane appeared unified as one membrane, but commonly also separated for various lengths. The EVi membrane was typically ... Epiretinal membranes (ERMs) are recognized by optical coherence tomography (OCT) as thin, hyperreflective bands anterior to the ... Epiretinal Membranes and Incomplete Posterior Vitreous Detachment in Diabetic Macular Edema, Detected by Spectral-Domain ... Epiretinal Membranes and Incomplete Posterior Vitreous Detachment in Diabetic Macular Edema, Detected by Spectral-Domain ...
Retina Consultants of Texas is one of the largest and most respected retina-only ophthalmology practices in the United States. We have four FDA-regulated research centers and are home to the Texas Retina Research Foundation, one of the countrys leading sites for retinal research. All Retina Consultants of Texas physicians are board-certified by the American Board of Ophthalmology and specialize exclusively in diseases and surgery of the retina, vitreous, and macula. In addition, we have an ocular oncology division, which focuses on cancer treatments for the eye. Our surgeons have studied at some of the most renowned institutions in the nation and all have graduated at the very top of their classes.. ...
These membranes have contractile properties and can lead to visual changes and metamorphopsia because of their effect on the ... Epimacular membranes (EMMs) are collections of collagenous cells that occur on the inner surface of the central retina. ... encoded search term (Epiretinal Membrane) and Epiretinal Membrane What to Read Next on Medscape ... Bovey EH, Uffer S. Tearing and folding of the retinal internal limiting membrane associated with macular epiretinal membrane. ...
Epiretinal Membrane , Prof. Dr. Şengül Özdek. Prof. Dr. Şengül Özdek. Göz Hastalıkları Uzmanı ...
This thin membrane of scarring tissue is called "epiretinal membrane" and can lead to mechanical distortion and wrinkling of ... This means that all patients with epiretinal membrane have enough vision to maintain their independence and move around with ... to assess the membrane and to see if there is edema (swelling) or leaking of the membrane in the retina.. In most cases there ... Epiretinal membrane​. The eye is like a photographic camera. It has the lens and an opening in front that help in the focusing ...
Macular pucker is a condition that causes blurriness and distortion in the center of your vision. Let our ophthalmologists treat your condition.
What is an Epiretinal Membrane?. An epiretinal membrane is a very thin layer of scar tissue which forms on the surface of the ... Assessment for an Epiretinal Membrane. We are able to detect an epiretinal membrane during an eye examination. Sometimes, a ... Why do I have an Epiretinal Membrane?. In most cases the development of an epiretinal membrane appears to be related to normal ... Epiretinal membranes are not related to macular degeneration. Epiretinal membranes do not usually affect the other eye. They ...
... Epiretinal membrane, also known as macular pucker, is a disease caused by the superficial ... The mildest cases of epiretinal membrane do not require treatment at all. The only treatment for a severe epiretinal membrane ... An epiretinal membrane is also called cellophane retinopathy, because the membrane structure resembles cellophane or plastic ... Central blind spots and cloudy vision may also develop as a result of progressed epiretinal membrane or macular pucker. ...
... Forlini M.;Date P.; ... To evaluate whether limited vitrectomy is as effective as complete vitrectomy in eyes with epiretinal membrane (ERM) and to ... To evaluate whether limited vitrectomy is as effective as complete vitrectomy in eyes with epiretinal membrane (ERM) and to ... A limited vitrectomy is a time-efficient and effective surgical procedure for removal of epiretinal membrane with no additional ...
Ornithine decarboxylase activity during formation of experimental epiretinal membranes. In: Current Eye Research. 1986 ; Vol. 5 ... Ornithine decarboxylase activity during formation of experimental epiretinal membranes. Victor W.Renardel de Lavalette, ... Ornithine decarboxylase activity during formation of experimental epiretinal membranes. Current Eye Research. 1986;5(2):101-104 ... Ornithine decarboxylase activity during formation of experimental epiretinal membranes. / de Lavalette, Victor W.Renardel; ...
... multifocal IOLs and stage 3 epiretinal membranes attained worse uncorrected acuity than eyes at stage 2 epiretinal membranes. ... Epiretinal Membrane in Eyes With Diffractive IOLs May Need Earlier Peeling. K. Patricia Bouweraerts, MA ... Kim H, Jeon S. Visual outcomes of epiretinal membrane removal after diffractive-type multifocal intraocular lens implantation. ... The most challenging aspect of epiretinal membrane (ERM) peeling may be timing - early removal presents a chance for the ...
Epiretinal membrane. ERM is an avascular, fibrocellular membrane on the inner surface of the retina (figure 6). ERM, also known ... Characterization of epiretinal membranes using optical coherence tomography. Ophthalmology 1996;103:2142-51. ... Optical coherence tomography of idiopathic macular epiretinal membranes before and after surgery. Am J Ophthalmol 2000;130:732- ... Three-dimensional evaluation of vitreomacular traction and epiretinal membrane using spectral-domain optical coherence ...
Retina/Vitreous This study suggests that only a small proportion of mild epiretinal membranes progress to req ... Observing epiretinal membranes until visually significant does not worsen surgical outcomes. reneschaub Send an email 9 hours ... Observing epiretinal membranes until visually significant does not worsen surgical outcomes. * 08/22/2022 Interview with The ... Home/Health/Vison/Observing epiretinal membranes until visually significant does not worsen surgical outcomes. Vison ...
To determine the prevalence of epiretinal membranes (ERMs) in Melbourne, Australia and its risk factors in this population.. ... The prevalence and risk factors of epiretinal membranes: the Melbourne collaborative cohort study. ...
Epiretinal membrane (Macular pucker). *Vitelliform macular dystrophy. *Lebers congenital amaurosis. *Birdshot ...
Understanding Epiretinal Membrane. Epiretinal membrane is a thin layer of tissue which is exceptionally sensitive when it comes ... Epiretinal membrane is not a major problem, what it will do though is distort your vision, which is ore frustrating than ... Scar tissue can form over the macula which then distorts the epiretinal membrane. As a result the macula doesnt work ... The best solution to repairing the epiretinal membrane and the side effects associated with it is surgery. Surgery is performed ...
Epiretinal membrane (macular pucker). Epiretinal membranes (ERMs) are also known as cellophane maculopathy. When the ERM ... Epiretinal membranes form on the inner surface of the retina, and resemble a wrinkled piece of cellophane. Overtime, the ERMs ...
The vacuole is formed primarily by invagination of the host cell plasma membrane, which is pulled over the parasite through the ... During invasion, the host cell is essentially passive and no change is detected in membrane ruffling, the actin cytoskeleton, ... Mitochondria shed their outer membrane in response to infection-induced stress. Science. 2022 Jan 14. 375 (6577):eabi4343. [ ... The Toxoplasma gondii parasitophorous vacuole membrane: transactions across the border. J Eukaryot Microbiol. 2007 Jan-Feb. 54( ...
... the basement membrane of the Müller cells, serves as the interface between the vitreous body and the retinal nerve fiber ... Epiretinal Membrane Removal. Epiretinal membrane (ERM) is a disease of the vitreomacular interface characterized by cellular ... Trypan blue (TB) is a dye that stains damaged cell membranes often used in epiretinal membrane removal in addition to ILM ... "Macular function and ultrastructure of the internal limiting membrane removed during surgery for idiopathic epiretinal membrane ...
Epiretinal Membrane Peeling February 5, 2019 :: :: How I replaced a steering lock cylinder on a 2008 Audi A3 :: ...
Keywords: Epiretinal Membrane, Internal Limiting Membrane, Optical coherence tomography, Vitrectomy Abstract. Objective: To ... Surgery in Preventing Postoperative Epiretinal Membrane (ERM) Formation * Asaad Mahmood Syed Layton Rehmatulla Benevolent Trust ... in preventing postoperative Epiretinal Membrane (ERM) formation; and its effect on the visual acuity. ... Syed, A. M., Syed, F. R., Khan, B. A. M., & Khan, T. H. (2021). Role of Concomitant Internal Limiting Membrane (ILM) Peeling ...
  • This study was to aggregate the prevalence and risks of epiretinal membranes (ERMs) and determine the possible causes of the varied estimates. (nih.gov)
  • Epiretinal membranes (ERMs) are recognized by optical coherence tomography (OCT) as thin, hyperreflective bands anterior to the retina or bright red bands in a pseudocolored OCT presentation. (arvojournals.org)
  • ERMs do not always progress quickly, thus evaluating membrane development is challenging. (ophthalmologyadvisor.com)
  • To determine the prevalence of epiretinal membranes (ERMs) in Melbourne, Australia and its risk factors in this population. (edu.au)
  • Epiretinal membranes (ERMs) are also known as cellophane maculopathy. (optometrists.org)
  • Idiopathic Epiretinal Membrane and Vitreomacular Traction Preferred Practice Pattern(®) Guidelines. (medscape.com)
  • Hosoda Y, Ooto S, Hangai M, Oishi A, Yoshimura N. Foveal Photoreceptor Deformation as a Significant Predictor of Postoperative Visual Outcome in Idiopathic Epiretinal Membrane Surgery. (medscape.com)
  • Surgical removal of idiopathic epiretinal membrane with or without the assistance of indocyanine green: a randomised controlled clinical trial. (medscape.com)
  • Small breaks in the internal limiting membrane (ILM) after PVD also may provide retinal astrocytes access to the vitreous cavity, where they may subsequently proliferate. (wikipedia.org)
  • Earlier reports proposed that glial cells (primarily fibrous astrocytes) from the inner layers of the neurosensory retina proliferated through breaks in the internal limiting membrane (ILM) produced after a retinal tear or a posterior vitreous detachment. (medscape.com)
  • In this retrospective and nonrandomized clinical trial, we evaluated 20 patients (20 eyes) who underwent 23 gauge transconjunctival PPV with internal limiting membrane peeling and air tamponade to treat ERM. (researchsquare.com)
  • Standard surgical procedure was core vitrectomy, removal of ERM and internal limiting membrane, fluid-air exchange. (researchsquare.com)
  • Bovey EH, Uffer S. Tearing and folding of the retinal internal limiting membrane associated with macular epiretinal membrane. (medscape.com)
  • Liu H, Zuo S, Ding C, Dai X, Zhu X. Comparison of the Effectiveness of Pars Plana Vitrectomy with and without Internal Limiting Membrane Peeling for Idiopathic Retinal Membrane Removal: A Meta-Analysis. (medscape.com)
  • Macular pucker: to peel or not to peel the internal limiting membrane? (medscape.com)
  • The internal limiting membrane (ILM), the basement membrane of the Müller cells, serves as the interface between the vitreous body and the retinal nerve fiber layer. (hindawi.com)
  • The internal limiting membrane (ILM) is the basal lamina of the inner retina that is formed by the footplates of Müller cells. (hindawi.com)
  • Henrich P.B. Nanoscale topographic and biomechanical studies of the human internal limiting membrane. (pmarchive.ru)
  • Posterior vitreous detachment (PVD) occurs when a dehiscence in the vitreous cortex allows fluid from a syneretic cavity to enter the potential subhyaloid space, causing the remaining hyaloid face to be stripped from the internal limiting membrane (ILM) of the retina (Fig 10-7). (aao.org)
  • To evaluate whether limited vitrectomy is as effective as complete vitrectomy in eyes with epiretinal membrane (ERM) and to compare the surgical times and rates of complications. (unime.it)
  • The only treatment for a severe epiretinal membrane is a surgical procedure called vitrectomy, in which the vitreous humor is removed from the eye followed by removal of the scar tissue. (retinacarecenternj.com)
  • Epiretinal membrane is typically diagnosed by appearance with optical coherence tomography (OCT) of the macula. (wikipedia.org)
  • In some patients, there may be some remnant vitreous gel on the macula, and some of the cells grow and form a membrane, similar to scar tissue, over the surface of the retina. (snec.com.sg)
  • The part of the eye affected by an epiretinal membrane is called the macula. (rcseattle.com)
  • When an epiretinal membrane forms over the macula, it may contract and wrinkle the macula resulting in distorted and/or blurred vision. (rcseattle.com)
  • Epiretinal membrane, also known as macular pucker, is a disease caused by the superficial folding of the central retina or macula by a thin fibrous membrane in the back of the eye. (retinacarecenternj.com)
  • Scar tissue can form over the macula which then distorts the epiretinal membrane. (yourhairlosstreatment.net)
  • Rahman R, Stephenson J. Early surgery for epiretinal membrane preserves more vision for patients. (medscape.com)
  • Kofod M, Christensen UC, la Cour M. Deferral of surgery for epiretinal membranes: Is it safe? (medscape.com)
  • Surgery is the only way to treat an epiretinal membrane, there are no eye drops or medications that you can take that will help. (rcseattle.com)
  • This study suggests that only a small proportion of mild epiretinal membranes progress to requiring surgery. (cutdoc.com)
  • The most challenging aspect of epiretinal membrane (ERM) peeling may be timing - early removal presents a chance for the membrane to reappear, although later surgery may impair restored visual acuity. (ophthalmologyadvisor.com)
  • OCT has been routinely used in measuring retinal thickness for the evaluation of ME caused by diseases such as age-related macular degeneration, diabetic retinopathy, hereditary retinal degenerations, retinal vein occlusion, after cataract surgery, epiretinal membrane (ERM) and uveitis. (bmj.com)
  • The best solution to repairing the epiretinal membrane and the side effects associated with it is surgery. (yourhairlosstreatment.net)
  • To evaluate the outcomes of epiretinal membrane (ERM) surgery in highly myopic eyes without traction maculopathy, and to compare them with those from non-highly myopic eyes. (entokey.com)
  • Purpose : To compare visual outcomes, intraoperative and postoperative complications of 25-gauge transconjunctival sutureless vitrectomy (25-G TSV) versus conventional 20-gauge vitrectomy in epiretinal membrane (ERM) surgery. (tokushima-u.ac.jp)
  • Epiretinal membrane formation without PVD may predispose patients to vitreomacular traction syndrome (VMT). (medscape.com)
  • ILM peeling is a surgical technique commonly used today to treat various vitreoretinal disorders including macular holes, macular puckers, epiretinal membranes, diabetic macular edema, retinal detachment, retinal vein occlusions, vitreomacular traction, optic pit maculopathy, and Terson syndrome [ 4 ]. (hindawi.com)
  • Epiretinal membranes can be associated with various ocular conditions, such as posterior vitreous detachments (PVD), retinal tears, retinal detachments , retinal vascular occlusive diseases, ocular inflammatory diseases, and vitreous hemorrhage . (medscape.com)
  • [ 2 ] They hypothesize that the presence of ILM tears and folds are more likely when the epiretinal membrane forms prior to a posterior vitreous detachment, resulting in the subsequent cleavage plane being between the ILM and the inner retina rather than at the ILM surface. (medscape.com)
  • To present the vitreoretinal interface in diabetic macular edema (DME) associated with both epiretinal membrane (ERM) and incomplete posterior vitreous detachment (PVD), as detected by spectral-domain optical coherence tomography (SD-OCT). (arvojournals.org)
  • A hyperreflective unified ERM/posterior vitreous cortex (PViC) membrane, or EVi membrane, was apparent in various sizes in 20 (87.0%) of the 23 eyes. (arvojournals.org)
  • In eyes with DME, ERM, and incomplete PVD, the posterior cortical vitreous and ERM appeared as one united EVi membrane in various lengths in most eyes, typically associated with vitreopapillary adhesion. (arvojournals.org)
  • With an RRD, cellular membranes may form on either surface (anterior or posterior) of the retina (Fig 10-9). (aao.org)
  • The source of the cells in epiretinal membranes (ERM) has been found to comprise glial cells, retinal pigment epithelial (RPE) cells, macrophages, fibrocytes, and collagen cells. (wikipedia.org)
  • Modern vitrectomy specimens have shown that epiretinal membranes comprise glial cells, retinal pigment epithelial cells, macrophages, fibrocytes, and collagen cells. (medscape.com)
  • Epiretinal membranes are avascular, fibrocellular membranes that proliferate on the surface of the retina and can lead to varying degrees of visual impairment. (medscape.com)
  • These cells, once in contact and attached to the retina, may proliferate and form sheets of membranes over the surface of the retina. (medscape.com)
  • An epiretinal membrane is a very thin layer of scar tissue which forms on the surface of the retina in an area that is responsible for our central and most important vision. (rcseattle.com)
  • Epiretinal membranes form on the inner surface of the retina, and resemble a wrinkled piece of cellophane. (optometrists.org)
  • Figure 10-9 Preretinal membrane (area between arrows) on the surface of the retina, secondary to proliferative vitreoretinopathy. (aao.org)
  • Very dense epiretinal membrane with associated macular distortion. (medscape.com)
  • This thin membrane of scarring tissue is called "epiretinal membrane" and can lead to mechanical distortion and wrinkling of the retina. (weebly.com)
  • To evaluate vision-related quality of life (VR-QOL) in patients with preoperative low vision who had previously removed epiretinal membrane (ERM) with pars plana vitrectomy, and compared the results with the control group (CG). (researchsquare.com)
  • In this retrospective study, we evaluated vision-related quality of life (VR-QOL) in patients with preoperative low vision who had previously removed epiretinal membrane (ERM) with pars plana vitrectomy (PPV), and compared the results with the control group (CG). (researchsquare.com)
  • This prospective study included patients scheduled for 23-G pars plana vitrectomy with membrane peeling due to epiretinal membranes. (karger.com)
  • However, a large proportion of cases do not occur in the context of any associated disease or known history and therefore are classified as idiopathic epimacular membranes (IEMM). (medscape.com)
  • These findings may have clinical importance in the context of epimacular membrane characteristics and its removal in DME. (arvojournals.org)
  • Karacorlu M, Ozdemir H, Senturk F, Karacorlu SA, Uysal O. Correlation of retinal sensitivity with visual acuity and macular thickness in eyes with idiopathic epimacular membrane. (medscape.com)
  • Charles S. Epimacular Membranes. (medscape.com)
  • Surgical treatment of lamellar macular hole associated with epimacular membrane. (medscape.com)
  • Aims To describe the prevalence of idiopathic and secondary epiretinal membranes (ERM) in a clinical cohort (Australian Heart Eye Study, AHES) and compare to the Blue Mountains Eye Study, and to determine whether associations exist between idiopathic ERM and the extent and severity of coronary artery disease (CAD). (edu.au)
  • 2 , 3 ] The 25-item NEI-VFQ-25 is preferred for evaluating the outcome of treatment of several eye diseases including cataract, keratoconus, glaucoma, age related macular degeneration, macular hole, epiretinal membrane (ERM), central serous chorioretinopathy, diabetic retinopathy, retinal vein occlusion and retinal detachment. (researchsquare.com)
  • A rare case with developing and spontaneous separation of Epiretinal Membrane (ERM) during the treatment of Branch Retinal Vein Occlusion (BRVO) and its clinical progression was presented. (alliedacademies.org)
  • The paper is devoted to the analysis of changes in the vitreo-retinal interface leading to various pathology processes such as epiretinal fibrosis. (pmarchive.ru)
  • The epiopathogenetic aspects of forming the idiopathic epiretinal fibrosis are considered, the possible mechanisms of formation and the most significant cell elements involved in the development and progression of the proliferation process. (pmarchive.ru)
  • all of which pertain to clinico-anatomic descriptions of pathologic findings produced by epiretinal membranes of varying severity and differing morphologic characteristics. (medscape.com)
  • Candiello J., Cole G.J., Halfter W. Age-dependent changes in the structure, composition and biophysical properties of a human basement membrane. (pmarchive.ru)
  • Anterior Basement Membrane Dystrophy. (slackbooks.com)
  • Surgeons can remove or peel the membrane through the sclera and improve vision by 2 or more Snellen lines. (wikipedia.org)
  • If problems with vision are significant, the membrane can be removed surgically with vitrectomy and membrane peel. (msdmanuals.com)
  • An epiretinal membrane (ERM) is a collection of collagenous cells that occurs on the inner surface of the central retina. (medscape.com)
  • Recovery of visual field and acuity after removal of epiretinal and inner limiting membranes. (medscape.com)
  • A limited vitrectomy is a time-efficient and effective surgical procedure for removal of epiretinal membrane with no additional complications. (unime.it)
  • Furthermore, since ILM removal has also been found to decrease the risk of epiretinal membrane development postoperatively, the indications for its application are broadened to include several vitreoretinal conditions [ 4 ]. (hindawi.com)
  • We can easily visualize the extent and severity of a macular epiretinal membrane and better grade diabetic retinopathy. (optos.com)
  • These disorders include floaters , retinal tear or detachment , macular degeneration , diabetic retinopathy , and epiretinal membrane . (medicalnewstoday.com)
  • Epiretinal membrane is formation of a thin, fibrotic membrane over the retina that contracts, wrinkling the underlying retina and interfering with vision. (msdmanuals.com)
  • Over time, these membrane cells can contract and cause the retina to wrinkle (or pucker), affecting and distorting vision. (snec.com.sg)
  • This means that all patients with epiretinal membrane have enough vision to maintain their independence and move around with relative comfort. (weebly.com)
  • Central blind spots and cloudy vision may also develop as a result of progressed epiretinal membrane or macular pucker. (retinacarecenternj.com)
  • Significant differences occurred, though, when comparing patients presenting stage 3 membrane with the superior uncorrected vision of control individuals: for UDVA, this difference was ( P =.035), and UNVA ( P =.029). (ophthalmologyadvisor.com)
  • Epiretinal membrane is not a major problem, what it will do though is distort your vision, which is ore frustrating than anything else, but you are sure to not loose your eye sight completely. (yourhairlosstreatment.net)
  • However, since epiretinal membrane appears to be a protective response to PVD, where inflammation, exudative fluid, and scar tissue is formed, it is possible that NSAIDs may reduce the inflammation response. (wikipedia.org)
  • Eyes with stage 3 membrane may have obtained reduced visual acuity due to changes in inner retinal structures, the investigators speculate, adding that light diffracted at the MIOL is diffracted again at the disrupted inner nuclear and plexiform layers - so even though a membrane is effectively peeled, the changed structures remain. (ophthalmologyadvisor.com)
  • It is the final stages of geographic RPE atrophy with possible development of choroidal neovascular membrane that is associated with further deterioration in acuity. (medscape.com)
  • Your ophthalmologist may ask you to do a fluorescein angiography (intravenous injection of a dye and pictures of the retina taken with a camera) or an Optical Coherence Tomography test (taking tomographic images of the retina using light) to assess the membrane and to see if there is edema (swelling) or leaking of the membrane in the retina. (weebly.com)
  • Sometimes, a special scan of the back of the eye (Optical Coherence Tomography) may be needed to confirm the presence of an epiretinal membrane. (rcseattle.com)
  • Hartzell HC, Qu Z, Yu K, Xiao Q, Chien LT. Molecular physiology of bestrophins: multifunctional membrane proteins linked to best disease and other retinopathies. (medscape.com)
  • Long-term anatomical and functional results in patients undergoing observation for idiopathic nontractional epiretinal membrane. (medscape.com)
  • If patients choose diffractive multifocal IOLs, they should first be carefully screened for epiretinal membrane risk. (ophthalmologyadvisor.com)
  • A Comparison of Intraoperative Dexamethasone Intravitreal Implant and Triamcinolone Acetonide Used During Vitrectomy and Epiretinal Membrane Peeling: A Case Control Study. (medscape.com)
  • In most cases the healing process is mild and leads to a very thin cellular membrane on the retinal surface. (weebly.com)
  • PVD can lead to retinal breaks that may liberate RPE cells that initiate membrane formation. (wikipedia.org)
  • The incidence of associated PVD in cases of IEMM range from 75-93%, and PVD is present in virtually all eyes with retinal breaks or retinal detachments and subsequent epiretinal membrane formation. (medscape.com)
  • It has been suggested that PVD may contribute to epiretinal membrane formation in many ways. (medscape.com)
  • Finally, vitreous hemorrhage, inflammation, or both associated with a PVD also may stimulate epiretinal membrane formation. (medscape.com)
  • Two had epiretinal membrane formation that was noncontractile. (medscape.com)
  • In some cases however, this process develops into an overproduction of cells that form a thicker, opaque membrane on the retinal surface. (weebly.com)
  • These membranes, which often have a contractile component, form as a result of proliferation of RPE cells and other cellular elements, including glial cells (Müller cells, fibrous astrocytes), histiocytes, fibroblasts, myofibroblasts, and possibly hyalocytes. (aao.org)