Blockage of the RETINAL VEIN. Those at high risk for this condition include patients with HYPERTENSION; DIABETES MELLITUS; ATHEROSCLEROSIS; and other CARDIOVASCULAR DISEASES.
Central retinal vein and its tributaries. It runs a short course within the optic nerve and then leaves and empties into the superior ophthalmic vein or cavernous sinus.
The vessels carrying blood away from the capillary beds.
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.
Central retinal artery and its branches. It arises from the ophthalmic artery, pierces the optic nerve and runs through its center, enters the eye through the porus opticus and branches to supply the retina.
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.
The administration of substances into the VITREOUS BODY of the eye with a hypodermic syringe.
The coagulation of tissue by an intense beam of light, including laser (LASER COAGULATION). In the eye it is used in the treatment of retinal detachments, retinal holes, aneurysms, hemorrhages, and malignant and benign neoplasms. (Dictionary of Visual Science, 3d ed)
The vein which drains the foot and leg.
An esterified form of TRIAMCINOLONE. It is an anti-inflammatory glucocorticoid used topically in the treatment of various skin disorders. Intralesional, intramuscular, and intra-articular injections are also administered under certain conditions.
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.
The blood vessels which supply and drain the RETINA.
The concave interior of the eye, consisting of the retina, the choroid, the sclera, the optic disk, and blood vessels, seen by means of the ophthalmoscope. (Cline et al., Dictionary of Visual Science, 4th ed)
Bleeding from the vessels of the retina.
A short thick vein formed by union of the superior mesenteric vein and the splenic vein.
A form of secondary glaucoma which develops as a consequence of another ocular disease and is attributed to the forming of new vessels in the angle of the anterior chamber.
Enlarged and tortuous VEINS.
The use of green light-producing LASERS to stop bleeding. The green light is selectively absorbed by HEMOGLOBIN, thus triggering BLOOD COAGULATION.
The vein accompanying the femoral artery in the same sheath; it is a continuation of the popliteal vein and becomes the external iliac vein.
The veins that return the oxygenated blood from the lungs to the left atrium of the heart.
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.
The administration of substances into the eye with a hypodermic syringe.
Veins in the neck which drain the brain, face, and neck into the brachiocephalic or subclavian veins.
Introduction of substances into the body using a needle and syringe.
Formation of new blood vessels originating from the retinal veins and extending along the inner (vitreal) surface of the retina.
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.
Sudden ISCHEMIA in the RETINA due to blocked blood flow through the CENTRAL RETINAL ARTERY or its branches leading to sudden complete or partial loss of vision, respectively, in the eye.
Conditions which affect the structure or function of the pupil of the eye, including disorders of innervation to the pupillary constrictor or dilator muscles, and disorders of pupillary reflexes.
Measurement of the blood pressure of the retinal vessels. It is used also for the determination of the near point of convergence (CONVERGENCE, OCULAR). (From Cline, et al., Dictionary of Visual Science, 4th ed)
Form of granulomatous uveitis occurring in the region of the pars plana. This disorder is a common condition with no detectable focal pathology. It causes fibrovascular proliferation at the inferior ora serrata.
Veins which return blood from the intestines; the inferior mesenteric vein empties into the splenic vein, the superior mesenteric vein joins the splenic vein to form the portal vein.
Three groups of arteries found in the eye which supply the iris, pupil, sclera, conjunctiva, and the muscles of the iris.
Short thick veins which return blood from the kidneys to the vena cava.
Venous vessels in the umbilical cord. They carry oxygenated, nutrient-rich blood from the mother to the FETUS via the PLACENTA. In humans, there is normally one umbilical vein.
A vein on either side of the body which is formed by the union of the external and internal iliac veins and passes upward to join with its fellow of the opposite side to form the inferior vena cava.
The blood pressure in the VEINS. It is usually measured to assess the filling PRESSURE to the HEART VENTRICLE.
Pathological processes involving any of the BLOOD VESSELS in the cardiac or peripheral circulation. They include diseases of ARTERIES; VEINS; and rest of the vasculature system in the body.
The most anterior portion of the uveal layer, separating the anterior chamber from the posterior. It consists of two layers - the stroma and the pigmented epithelium. Color of the iris depends on the amount of melanin in the stroma on reflection from the pigmented epithelium.
Examination of the interior of the eye with an ophthalmoscope.
Diseases affecting the eye.
The pressure of the fluids in the eye.
The therapy of the same disease in a patient, with the same agent or procedure repeated after initial treatment, or with an additional or alternate measure or follow-up. It does not include therapy which requires more than one administration of a therapeutic agent or regimen. Retreatment is often used with reference to a different modality when the original one was inadequate, harmful, or unsuccessful.
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.
A glucocorticoid given, as the free alcohol or in esterified form, orally, intramuscularly, by local injection, by inhalation, or applied topically in the management of various disorders in which corticosteroids are indicated. (From Martindale, The Extra Pharmacopoeia, 30th ed, p739)
Hemorrhage into the VITREOUS BODY.
Veins which drain the liver.
A group of CORTICOSTEROIDS that affect carbohydrate metabolism (GLUCONEOGENESIS, liver glycogen deposition, elevation of BLOOD SUGAR), inhibit ADRENOCORTICOTROPIC HORMONE secretion, and possess pronounced anti-inflammatory activity. They also play a role in fat and protein metabolism, maintenance of arterial blood pressure, alteration of the connective tissue response to injury, reduction in the number of circulating lymphocytes, and functioning of the central nervous system.
A hypoperfusion of the BLOOD through an organ or tissue caused by a PATHOLOGIC CONSTRICTION or obstruction of its BLOOD VESSELS, or an absence of BLOOD CIRCULATION.
The vein formed by the union of the anterior and posterior tibial veins; it courses through the popliteal space and becomes the femoral vein.
The internal resistance of the BLOOD to shear forces. The in vitro measure of whole blood viscosity is of limited clinical utility because it bears little relationship to the actual viscosity within the circulation, but an increase in the viscosity of circulating blood can contribute to morbidity in patients suffering from disorders such as SICKLE CELL ANEMIA and POLYCYTHEMIA.
The condition of an anatomical structure's being constricted beyond normal dimensions.
A bright bluish pink compound that has been used as a dye, biological stain, and diagnostic aid.
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)
Agents and endogenous substances that antagonize or inhibit the development of new blood vessels.
The use of photothermal effects of LASERS to coagulate, incise, vaporize, resect, dissect, or resurface tissue.
Recording of electric potentials in the retina after stimulation by light.
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).
An electrochemical technique for measuring the current that flows in solution as a function of an applied voltage. The observed polarographic wave, resulting from the electrochemical response, depends on the way voltage is applied (linear sweep or differential pulse) and the type of electrode used. Usually a mercury drop electrode is used.
A low-molecular-weight fragment of heparin, prepared by nitrous acid depolymerization of porcine mucosal heparin. The mean molecular weight is 4000-6000 daltons. It is used therapeutically as an antithrombotic agent. (From Merck Index, 11th ed)
The continuation of the axillary vein which follows the subclavian artery and then joins the internal jugular vein to form the brachiocephalic vein.
Vein formed by the union (at the hilus of the spleen) of several small veins from the stomach, pancreas, spleen and mesentery.
Diseases, dysfunctions, or disorders of or located in the iris.
Artery originating from the internal carotid artery and distributing to the eye, orbit and adjacent facial structures.
An autosomal dominant disorder showing decreased levels of plasma protein S antigen or activity, associated with venous thrombosis and pulmonary embolism. PROTEIN S is a vitamin K-dependent plasma protein that inhibits blood clotting by serving as a cofactor for activated PROTEIN C (also a vitamin K-dependent protein), and the clinical manifestations of its deficiency are virtually identical to those of protein C deficiency. Treatment with heparin for acute thrombotic processes is usually followed by maintenance administration of coumarin drugs for the prevention of recurrent thrombosis. (From Harrison's Principles of Internal Medicine, 12th ed, p1511; Wintrobe's Clinical Hematology, 9th ed, p1523)
Surgery performed on the eye or any of its parts.
Veins draining the cerebrum.
The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve.
The thin, highly vascular membrane covering most of the posterior of the eye between the RETINA and SCLERA.
Antibodies from non-human species whose protein sequences have been modified to make them nearly identical with human antibodies. If the constant region and part of the variable region are replaced, they are called humanized. If only the constant region is modified they are called chimeric. INN names for humanized antibodies end in -zumab.
Reduction of blood viscosity usually by the addition of cell free solutions. Used clinically (1) in states of impaired microcirculation, (2) for replacement of intraoperative blood loss without homologous blood transfusion, and (3) in cardiopulmonary bypass and hypothermia.
A surgical operation for the relief of pressure in a body compartment or on a body part. (From Dorland, 28th ed)
Method of making images on a sensitized surface by exposure to light or other radiant energy.
Intraocular hemorrhage from the vessels of various tissues of the eye.
The original member of the family of endothelial cell growth factors referred to as VASCULAR ENDOTHELIAL GROWTH FACTORS. Vascular endothelial growth factor-A was originally isolated from tumor cells and referred to as "tumor angiogenesis factor" and "vascular permeability factor". Although expressed at high levels in certain tumor-derived cells it is produced by a wide variety of cell types. In addition to stimulating vascular growth and vascular permeability it may play a role in stimulating VASODILATION via NITRIC OXIDE-dependent pathways. Alternative splicing of the mRNA for vascular endothelial growth factor A results in several isoforms of the protein being produced.
A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
A vein which arises from the right ascending lumbar vein or the vena cava, enters the thorax through the aortic orifice in the diaphragm, and terminates in the superior vena cava.
The minute vessels that connect the arterioles and venules.
Large veins on either side of the root of the neck formed by the junction of the internal jugular and subclavian veins. They drain blood from the head, neck, and upper extremities, and unite to form the superior vena cava.
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)
A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma.
The flow of BLOOD through or around an organ or region of the body.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
The clear, watery fluid which fills the anterior and posterior chambers of the eye. It has a refractive index lower than the crystalline lens, which it surrounds, and is involved in the metabolism of the cornea and the crystalline lens. (Cline et al., Dictionary of Visual Science, 4th ed, p319)
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)
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
The venous trunk of the upper limb; a continuation of the basilar and brachial veins running from the lower border of the teres major muscle to the outer border of the first rib where it becomes the subclavian vein.

Chronic retinal vein occlusion in glaucoma. (1/210)

Asymptomatic chronic retinal vein occlusion that occurs in chronic simple glaucoma is described. The condition is characterized by marked elevation of retinal vein pressure with collateral vessels and vein loops at the optic disc in cases of central vein occlusion, or retinal veno-venous anastomoses along a horizontal line temporal and nasal to the disc in hemisphere vein occlusion. No patient had visible arterial changes, capillary closure, fluorescein leakage, or haemorrhages. The vein occlusion was not limited to "end stage" glaucoma. The role of increased intraocular pressure and glaucomatous enlargement of the optic cup with retinal vein distortion in the pathogenesis of the condition was stressed. Follow-up of these patients revealed persistence of the retinal vein occlusion shown by elevated retinal vein pressures. This would reduce effective perfusion of the inner retina and optic disc and may affect the long-term visual prognosis.  (+info)

Microvasculature of the rat optic nerve head. (2/210)

PURPOSE: To describe the arterial blood supply, capillary bed, and venous drainage of the rat optic nerve head. METHODS: Ocular microvascular castings from 6 Wistar rats were prepared by injection of epoxy resin through the common carotid arteries. After polymerization, tissues were digested with 6 M KOH, and the castings washed, dried, and coated for scanning electron microscopy. RESULTS: Immediately posterior to the globe, the ophthalmic artery trifurcates into the central retinal artery and two posterior ciliary arteries. The central retinal artery directly provides capillaries to the nerve fiber layer and only contributes to capillary beds in the neck of the nerve head. The remainder is supplied by branches of the posterior ciliary arteries that are analogous to the primate circle of Zinn-Haller. Arterioles arising from these branches supply the capillaries of the transitional, or laminar, region of the optic nerve head. These capillaries are continuous with those of the neck and retrobulbar optic nerve head. All optic nerve head capillaries drain into the central retinal vein and veins of the optic nerve sheath. A flat choroidal sinus communicates with the central retinal vein, the choriocapillaris, and with large veins of the optic nerve sheath. CONCLUSIONS: The microvasculature of the rat optic nerve head bears several similarities to that of the primate, with a centripetal blood supply from posterior ciliary arteries and drainage into the central retinal and optic nerve sheath veins. Association of nerve sheath veins with the choroid represents an important difference from the primate.  (+info)

Optic nerve and peripapillary choroidal microvasculature of the rat eye. (3/210)

PURPOSE: To investigate the three-dimensional microvascular anatomy of the optic nerve and peripapillary choroid in the rat eye. METHODS: Gross vascular anatomy of the posterior eye segment of Wistar rats was studied in serial microsections with a light microscope. The optic nerve and peripapillary choroidal vessels were sequentially microdissected, using methylmethacrylate corrosion microvascular castings, and were examined with a scanning electron microscope to determine the three-dimensional relationships of the vessels. RESULTS: The posterior ciliary artery traveled along the inferior side of the optic nerve sheath, directly entered the optic nerve head, and divided into three branches: the central retinal artery and medial and lateral long posterior ciliary arteries, which provided several short branches to the choroid. The optic nerve head vasculature was consistently nourished by a recurrent arteriole from the central retinal artery and an arteriole from the choroidal artery at the peripapillary choroid. The central retinal vein flowed into a venous anastomosis along the optic disc border of the peripapillary choroid. Capillaries within the optic nerve drained into the central retinal vein, the marginal venous anastomosis of the peripapillary choroid, and the pial veins, all of which flowed into the posterior ciliary veins along the optic nerve sheath. CONCLUSIONS: The findings illustrate vascular anatomic differences in optic nerve and peripapillary choroidal microcirculation between rat and human. In rats, the peripapillary choroid plays a significant role in both blood supply and venous drainage of the optic nerve head. The central retinal artery also contributes to the optic nerve head circulation.  (+info)

Polymerase chain reaction for detection of Mycobacterium tuberculosis in epiretinal membrane in Eales' disease. (4/210)

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)

Laser treatment and the mechanism of edema reduction in branch retinal vein occlusion. (5/210)

PURPOSE: To test a hypothesis on the physiological mechanism of the disappearance of macular edema after laser treatment. The hypothesis is based on the effect grid laser treatment has on retinal oxygenation and hemodynamics. It predicts that laser-induced reduction of macular edema is associated with shortening and narrowing of retinal vessels in patients with branch retinal vein occlusion (BRVO). METHODS: The study included 12 subjects, treated with argon laser photocoagulation for BRVO and macular edema. Fundus photographs taken at the time of diagnosis and again after laser treatment, were digitized, and diameter and segment length of retinal vessels was measured using NIH-Image program. RESULTS: Macular edema disappeared or was dramatically reduced in all cases after laser treatment. The diameter of occluded venules constricted to 0.81+/-0.02 (mean +/- SD, P = 0.019) of the prelaser diameter and adjacent arterioles constricted to 0.78+/-0.01 (P = 0.008). The laser treatment also led to shortening of the affected vessels. The final segment length of the occluded venules was 0.95+/-0.17 (P = 0.005) of the length before treatment. The corresponding value for the adjacent arterioles is 0.95+/-0.14 (P = 0.008). Control arterioles and venules in the same fundus did not change in either length or width. CONCLUSIONS: These results do not reject the authors' hypothesis that the disappearance of macular edema in BRVO can be explained by the effect the laser photocoagulation has on retinal oxygenation. Increased oxygenation causes vessel constriction and shortening and lower intravascular pressure, which reduces edema formation according to Starling's law.  (+info)

Experimental preretinal neovascularization by laser-induced thrombosis in albino rats. (6/210)

The primary objective of this study was to develop a simple experimental model of angiogenesis by photodynamic thrombosis of the retinal veins in Sprague-Dawley rats. After a tail vein injection of rose bengal (40 mg/kg), all major retinal veins adjacent to the optic nerve head were photocoagulated with an argon green laser. The eyes were examined regularly for the following eight weeks. A grading system was devised using fluorescein angiograms and ADPase staining to describe the progression of the new vessels. Nine out of ten eyes showed development of the preretinal new vessels by day 14. Seven weeks after laser coagulation, 2 of 5 eyes developed localized tractional retinal detachment. Regression of the neovascularization was not noted in any of the animals during the follow-up period. The authors were able to establish an experimental model for preretinal neovascularization by vein occlusion. This model may be applied in study of the pathogenesis and treatment of retinal neovascularization.  (+info)

Bilateral simultaneous retinal vein occlusion. (7/210)

Central retinal vein occlusion (CVO) is a common retinal vascular disorder with potentially blinding complications. However, a simultaneous bilateral affection is not a common entity. One such patient is described here.  (+info)

Colour Doppler imaging of the orbital vasculature in Graves' disease with computed tomographic correlation. (8/210)

AIMS: To evaluate alterations in orbital blood flow parameters and their correlations with extraocular muscle enlargement, proptosis, and intraocular pressure in patients with Graves' disease. METHODS: In this multicentre study blood flow parameters in the ophthalmic artery, superior ophthalmic vein, central retinal artery and vein were determined by colour Doppler imaging in 111 patients with Graves' disease in two groups (A and B) and 46 normal control subjects. Group A consisted of 42 patients with Graves' disease without ophthalmopathy; group B of 69 patients with Graves' disease with ophthalmopathy as detected by orbital computed tomographic scanning. RESULTS: Peak systolic and end diastolic velocities in the ophthalmic artery, peak systolic velocity in the central retinal artery, and maximal and minimal velocities in the central retinal vein in patients in group B were statistically significantly higher than those in group A and the normal controls, whereas maximal and minimal velocities in the superior ophthalmic vein in patients in group B were statistically significantly lower than those in group A and the control subjects. Peak systolic and end diastolic velocities in the ophthalmic artery, peak systolic velocity in the central retinal artery, and maximal and minimal velocities in the central retinal vein also correlated with the sum of all extraocular muscle diameters in group B (r > or =0.31, p< or =0.021). Blood flow parameters had no consistent correlation with proptosis or intraocular pressure (p>0.05). No statistically significant difference was found in resistivity indices between the groups (p>0.05). Reversed blood flow was noted in nine (13%) superior ophthalmic veins in group B. CONCLUSION: Orbital blood flow velocities are altered in patients with Graves' ophthalmopathy and may be detected by colour Doppler imaging. Some of these changes also correlate with the enlargement of extraocular muscles. The increased blood flow velocities in arteries may be secondary to orbital inflammation.  (+info)

Objective: To describe a new computer-assisted method to measure retinal vascular caliber over an extended area of the fundus. Methods: Retinal photographs taken from participants of the Singapore Malay Eye Study (n = 3280) were used for this study. Retinal vascular caliber was measured and summarized as central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) using a new semi-automated computer-based program. Measurements were made at the Standard zone (from 0.5 to 1.0 disk diameter) and an Extended zone (from 0.5 to 2.0 disk diameter). Results: Reliability of retinal vascular caliber measurement was high for the new Extended zone (intraclass correlation coefficients >0.90). Associations of CRAE with blood pressure were identical between the Extended and Standard zones (linear regression coefficient -2.53 vs. -2.61, z-test between the two measurements, p = 0.394). Associations of CRAE and CRVE with other cardiovascular risk factors were similar between measurements ...
Purpose: To determine the diagnostic ability of retinal vessel diameter (RVD) measurements and the factors related to retinal vascular diameters in patients with open-angle glaucoma (OAG). Methods: This retrospective observational study included 145 patients with OAG (63 with high-tension and 82 with low-tension glaucoma) and 60 healthy controls. The central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were measured using the IVAN software version 1.3. Receiver operating characteristic (ROC) curves were obtained for the average retinal nerve fiber layer (RNFL) thickness and RVD indices including CRAE, CRVE, and CRAE/CRVE ratio. Areas under the ROC curves (AUCs), 95% confidence intervals (CIs), and sensitivities at a fixed specificity (,90% and ,80%) were calculated. Factors related to CRAE were analyzed by simple and multiple linear regression analyses. Results: Among the RVD indices, the CRAE had the largest AUC for discriminating glaucomatous changes ...
Eleven patients with a central retinal vein obstruction and 18 with tributary vein obstruction were examined. The intraocular pressure of both eyes of each subject was measured while he was in the sitting position and again after he had been lying down for 15 minutes. Tonography was then carried out on both eyes. No correlation was found between the value of the coefficient of outflow and the magnitude of the rise in intraocular pressure occurring in any eye on the adoption of the supine position, and no correlation between the relative values of the coefficients of outflow in any pair of eyes and the occurrence of the obstruction in one eye rather than the other. ...
In accordance with an embodiment of the present technique, there is provided methods and systems for detecting the presence of venous pulsation by adjusting the sensitivity of a detection algorithm based on a sensor characteristic and/or notifying a caregiver of the presence of venous pulsation by ceasing display of physiological parameters. An exemplary embodiment includes receiving one or more signals from a sensor, the one or more signals corresponding to absorption of light in a patients tissue; calculating one or more physiological parameters of the patient based on the one or more signals; displaying the patients physiological parameters; enabling detection of venous pulsation with variable sensitivity based on a location of the sensor; and suspending or terminating the display of the one or more of the patients physiological parameters when venous pulsation is detected.
Our study data may have several potential research and clinical implications. First, the importance of studying topological variations of the retinal vasculature has gained increasing recognition. 57 58 59 Despite numerous studies of the retinal vascular caliber in adults, the reference data for this important vascular feature remains unclear as different population-based studies have shown different values. This may be related to reliability issues with the various algorithms used to calculate the retinal vascular caliber, the various prevalences of refractive errors in different populations, and most important, the inability to completely control for confounding effect from systemic (e.g., blood pressure, medication, diabetes, smoking) and ocular (e.g., glaucoma, diabetic retinopathy) disease processes in the adult populations. Our study represents the first attempt to provide reference data for the retinal vascular calibers in healthy school-aged children, which may be helpful in future ...
In this population-based study of persons free of clinical cardiovascular disease, we show that wider retinal venular caliber is associated with reduced brachial FMD, independent of traditional cardiovascular risk factors. Our study suggests that retinal venular caliber may reflect underlying systemic endothelial dysfunction, and that this may provide a novel explanation of why retinal venular caliber predicts incident stroke and other cardiovascular events.. To our best knowledge, there has only been one published study with which to compare our findings. An analysis from the Hoorn study of 256 persons 60 to 85 years of age (of 631 eligible, with 6 missing retinal photographs and 52 missing FMD) showed that after controlling for age, sex, glucose tolerance, baseline diameter, and increase in peak systolic velocity, wider venules were associated with reduced brachial FMD,17 although this was not statistically significant.. Our study findings may provide additional insights into previously ...
Objective: To evaluate the relationship between retinal vascular caliber and cardiovascular disease in non-alcoholic fatty liver disease (NAFLD) patients without diabetes and hypertension. Methods: Intention to treat study of individuals who underwent cardiac computed tomography (CT) during a two year period. Coronary artery disease (CAD) was defined as stenosis of >50% in at least one major coronary artery. Liver and spleen density were measured by abdominal (CT); intima-media thickness (IMT) by Doppler ultrasound; retinal artery and vein diameter by colored-retinal angiography; and metabolic syndrome by ATP III guidelines. Serum biomarkers of insulin resistance, inflammation, and oxidant-antioxidant status were assessed. Results: Compared with 22 gender and age matched controls, the 29 NAFLD patients showed higher prevalence of coronary plaques (70% vs. 30%, p < 0.001), higher prevalence of coronary stenosis (30% vs. 15%, p < 0.001), lower retinal arteriole-to-venule ratio (AVR) (0.66 ± 0
Adult participants are recruited in Cape Town and Worcester (South Africa). Participants are enrolled in the HIV-negative control group, the HIV-positive ART naïve group and the HIV-positive ART group. Baseline examination and a follow-up examination after 18 months are done. The examination consists of a health questionnaire, anthropometric measurements, cardiovascular measurements (flow-mediated dilatation, intima media thickness and retinal analysis), blood and urine chemistry. Here, we report the widths of retinal blood vessels, represented as the central retinal arteriolar/venular equivalent (CRAE/CRVE), and the arteriovenous ratio (AVR ...
Pigmented paravenous chorioretinal atrophy (PPCRA) [MIM:172870]: Unusual retinal degeneration characterized by accumulation of pigmentation along retinal veins. PPCRA is dominantly inherited, but exhibited variable expressivity. Males are more likely to exhibit a severe phenotype, whereas females may remain virtually asymptomatic even in later years. The PPCRA phenotype is associated with a mutation in CRB1 gene which is likely to affect the structure of the CRB1 protein. {ECO:0000269,PubMed:15623792}. Note=The disease is caused by mutations affecting the gene represented in this entry ...
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Our findings are consistent with those from a recent cohort study based on healthcare claims databases from the United States. The study reported an increased incidence rate (incidence rate ratio 1.72, 95% confidence interval 1.27 to 2.34) of cerebrovascular disease and a higher comorbidity index in patients with retinal vein occlusion compared with the general population.19 It also reported that the event rates for myocardial infarction were similar in patients with retinal vein occlusion and controls. The conclusion persisted after a subgroup analysis was performed for people with branch retinal vein occlusion and central retinal vein occlusion.. Studies from Taiwan found that retinal vein occlusion was not independently associated with an increased risk of acute myocardial infarction, and an association between incident stroke and retinal vein occlusion was found only in the subgroup of patients aged 60-69.21 22 Other follow-up studies with fewer observations have found less consistent ...
Central Retinal Vein Occlusion (CRVO) is caused by a blood clot in the vein that drains the blood from the retina of the eye. People suffering from the disease in Floral Park may want to read on and get more information about its symptoms, prevention and treatment.
DEXAMETHASONE AND RANIBIZUMAB AS TREATMENT FOR CENTRAL RETINAL VEIN OCCLUSION: A quality assessment of the efficacy of Dexamethasone and Ranibizumab following a central retinal vein occlusion at the department of Ophthalmology, Örebro University Hospital ...
When a peripheral retinal vein is occluded, this is called a branch retinal vein occlusion (BRVO). In a BRVO, swelling (edema) and hemorrhage are usually limited to one part of the retina. When the main vein draining the eye is occluded, this is called a central retinal vein occlusion (CRVO). In a CRVO, edema and hemorrhage can involve the entire retina resulting in more severe vision loss.. The retinal blood supply consists of arteries and veins. Arteries supply blood to the retina and veins drain blood from the retina. Occlusions, or blockages, in a retinal vein can occur for various reasons. The most common reason for a retinal vascular occlusion is atherosclerosis, or hardening of the arteries, that occurs with increasing age, high blood pressure, or high cholesterol.. When a retinal vein is blocked, blood has difficulty draining the eye. This leads to back pressure on the vessels and spillage of blood and fluid into the retinal tissue. If blood and fluid (macular edema) build up in the ...
The central retinal vein is the venous equivalent of the central retinal artery and, like that blood vessel, it can suffer from occlusion (central retinal vein occlusion, also CRVO[1]), similar to that seen in ocular ischemic syndrome. Since the central retinal artery and vein are the sole source of blood supply and drainage for the retina, such occlusion can lead to severe damage to the retina and blindness, due to ischemia (restriction in blood supply) and edema (swelling).[2] It can also cause glaucoma. Nonischemic CRVO is the milder form of the disease. It may progress to the more severe ischemic type.[3] ...
Another name for Retinal Vein Occlusion is Central Retinal Vein Occlusion. Symptoms of central retinal vein occlusion include: * Vision change: - Sudden ...
Critical appraisal of the clinical utility of the dexamethasone intravitreal implant (Ozurdex®) for the treatment of macular edema related to branch retinal vein occlusion or central retinal vein occlusion Annie Chan, Loh-Shan Leung, Mark S BlumenkranzDepartment of Ophthalmology, Stanford University School of Medicine, Stanford, CA, USAAbstract: Macular edema is a common cause of visual loss in patients with retinal vein occlusions. Ozurdex®, a dexamethasone intravitreal implant, has been shown in randomized controlled trials to reduce macular edema and improve visual acuity in patients with either branch retinal vein occlusions or central retinal vein occlusions. It was approved in the United States in 2009. Since then, new therapeutic agents and clinical data have emerged. The purpose of this review is to critically evaluate the clinical utility of Ozurdex® in the current treatment strategy of macular edema related to retinal vein occlusion.Keywords: macular edema, branch retinal vein
Central retinal vein occlusion (CRVO) is a common retinal vascular disorder. Clinically, CRVO presents with variable visual loss; the fundus may show retinal hemorrhages, dilated tortuous retinal veins, cotton-wool spots, macular edema, and optic disc edema.
Central retinal vein occlusions occur when a thrombotic obstruction occurs in the central vein of the retina and is essentially a blockage of the portion of the circulation that drains the retina of blood. The result is a sudden complete retinal hemorrhage (bleeding) throughout the four quadrants of the retina, as well as optic nerve disc edema (swelling) and dilated, tortuous retinal veins. The major symptom you as patient will experience is a sudden complete loss of vision in one or both eyes.. Reasons for developing CRVO may involve abnormal blood flow or blood constituents (blood plasma, erythrocytes, leukocytes, and thrombocytes), atherosclerosis and vessel anomalies. Properties of blood and the vein itself act in concert to cause thrombus formation, which impedes venous blood flow from the retina.. Other associated risk factors include systemic diseases like Hypertension, Glaucoma, Diabetes mellitus, Cardiovascular disease, Anemia, Carotid artery obstruction, Hyperviscosity syndromes, ...
Before Its News). Retinal Vein Occlusion-Pipeline Insights, 2016″, report provides in depth insights on the pipeline drugs and their development activities around the Retinal Vein Occlusion. The Report covers the product profiles in various stages of development including Discovery, Pre-clinical, IND, Phase I, Phase II, Phase III and Preregistration. Report covers the product clinical trials information and other development activities including technology, licensing, collaborations, acquisitions, fundings, patent and USFDA & EMA designations details. Report also provides detailed information on the discontinued and dormant drugs that have gone inactive over the years for Retinal Vein Occlusion. Report also assesses the Retinal Vein Occlusion therapeutics by Monotherapy, Combination products, Molecule type and Route of Administration.. For more information about this report: Table of Contents. - Retinal Vein Occlusion ...
Branch retinal vein occlusion is a more common type of retinal vascular occlusion. Treatment options are usually very successful in regaining vision. The post Branch Retinal Vein Occlusion , BRVO appeared first on Retina Specialist , Fairfax, Virginia , Retinal Diseases.. Full Story →. ...
Central retinal vein occlusion (CRVO) is the most common disease of the retinal vessels. It refers to a blockage of the vein draining the retinal tissue at the back of the eye. Occurring mostly in the elderly or middle-aged, it causes a subacute loss of vision.
PURPOSE: To evaluate the long-term safety and efficacy of intravitreal bevacizumab injections (Avastin, Genentech Inc., San Francisco, CA) for the treatment of macular edema secondary to central retinal vein occlusions.. METHODS: A retrospective review was performed of eyes treated from May 2005 to August 2006 with follow-up through February 2007. The dose of bevacizumab was 1.25 mg (0.05 mL). Retreatment was performed at monthly or longer intervals at the discretion of the treating physician.. RESULTS: Fifty-seven eyes received intravitreal bevacizumab at baseline. Visual acuity improved by a mean of 14 letters (N = 53; P , 0.001) at 1 month, 13 letters at 3 months (N = 53; P , 0.001), 9 letters at 6 months (N = 30; P = 0.001), 9 letters at 12 months (N = 17; P = 0.004). The mean optical coherence tomography thickness decreased by 299 microm at 1 month (N = 53; P , 0.001), 144 microm at 3 months, (N = 53; P , 0.001), 127 microm at 6 months (N = 30; P = 0.011), and 276 microm at 12 months (N = ...
Tuberculosis remains a major international public health concern, with the global incidence rate increasing approximately 0.4% per year, but much faster in sub-Saharan Africa and Eastern Europe;1 the effect that HIV has on incidence is also highly significant.2 Within the UK the incidence of tuberculosis varies considerably between regions and ethnic groups, with rates increasing significantly among recent immigrants.3. This case describes a patient who presented with central retinal vein occlusion (CRVO) who was subsequently diagnosed with tuberculosis ...
Monthly eye injections of Avastin (bevacizumab) are as effective as the more expensive drug Eylea (aflibercept) for the treatment of central retinal vein occlusion (CRVO), according to a clinical trial funded by the National ...
The Report Central Retinal Vein Occlusion Global Clinical Trials Review, H2, 2016 provides information on pricing, market analysis, shares, forecast, and...
Purpose: To investigate aqueous humor nitric oxide (NO) levels in patients with branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) and to compare these with age-matched controls. Methods: Eight consecutive patients with BRVO and 16 patients with CRVO were included in this study. Aqueous humor specimens were ...
The central retinal vein (retinal vein) is a short vein that runs through the optic nerve, leaves the optic nerve 10 mm from the eyeball and drains blood from the capillaries of the retina into either superior ophthalmic vein or into the cavernous sinus directly. The anatomy of the veins of the orbit of the eye varies between individuals, and in some the central retinal vein drains into the superior ophthalmic vein, and in some it drains directly into the cavernous sinus.[1][2] ...
When a retinal vein is blocked, it cannot drain blood from the retina. This leads to hemorrhages (bleeding) and leakage of fluid from the blocked blood vessels. There are two types of retinal vein occlusion: Central retinal vein occlusion (CRVO) is the blockage of the main retinal vein. Branch retinal vein occlusion (BRVO) is the blockage of one of the smaller branch veins.. Nerve cells need a constant supply of blood to deliver oxygen and nutrients and blood vessels provide this supply. Most people understand what happens in a stroke: a small blood clot blocks the flow of blood through one of the arteries in the brain, and the area that is not getting blood becomes damaged. This same type of damage can happen anywhere in the body, not just the brain.. ...
PURPOSE: To evaluate the feasibility, safety, and efficacy of local thrombolytic agents directly injected into occluded retinal veins in an experimental animal model.DESIGN: Experimental animal study.METHODS: This experimental study was performed in two phases. in phase 1, 15 enucleated porcine eyes and 8 in vivo canine eyes were used for the development of the instrumentation and surgical technique required for retinal vein cannulation with prolonged intravascular infusion. in phase 2 of this study, experimental branch retinal vein occlusion was photo,chemically created using an intravenous injection of rose bengal followed by diode laser photo coagulation in eight eyes of eight dogs. Four eyes were treated by retinal vein cannulation and an injection of tissue Plasminogen activator (t-PA) using a specifically designed microcatheter, while the remaining four eyes were untreated (control group). the total amount of t-PA injected intravenously ranged from 400 to 1000 mug, infused over a period ...
Twelve-month outcomes in patients with retinal vein occlusion treated with low-frequency intravitreal ranibizumab Yoshihito Sakanishi, Ami Lee, Ayumi Usui-Ouchi, Rei Ito, Nobuyuki Ebihara Department of Ophthalmology, Juntendo University Urayasu Hospital, Urayasu City, Chiba, Japan Purpose: The purpose of this study was to determine the clinical efficacy of low-frequency intravitreal ranibizumab to treat macular edema due to retinal vein occlusion (RVO).Patients and methods: This was a retrospective examination of cases that received intravitreal ranibizumab for untreated RVO over a period of 12 months. Instead of the conventional three monthly injections, injections were given once during the introductory period. If the recurrence of macular edema was diagnosed during the monthly visit, additional injections were given as needed. There were 21 eyes of 21 patients with branch RVO (BRVO) and ten eyes of ten patients with central RVO (CRVO). The parameters examined included the number of injections
This study will investigate tenecteplase compared to placebo on intravenous thrombus and retinal blood flow in patients with branch retinal vein occlusion.
The primary symptom of retinal vein occlusion is a blurring or loss of vision thats usually sudden in onset and generally in only one eye. If it isnt treated, the blurring or loss of vision usually gets worse in hours or days. Sometimes, youll see dark spots or floaters, which are tiny clumps of cells or material floating in your eye. In severe cases, a blocked vein will build up pressure and cause pain in your eye.. Its important to see your doctor right away if you have these symptoms because a retinal vein occlusion can lead to other health problems.. ...
Retinal Vein Occlusion - Pipeline Review, H2 2017Global Markets Directs latest Pharmaceutical and Healthcare disease pipeline guide Retinal Vein Occlusion - Pipeline Review, H2 2017, provides an overview of the
A total of 53 patients with central retinal vein occlusion (CRVO) were distributed to Group 1: Central retinal vein occlusion treated with ranibizumab (43 patients) and Group 2: central retinal vein occlusion treated with aflibercept (10 patients). The diagnosis evaluation of the CRVO begins with an anamnesis review and a complete ophthalmologic examination. Cooperation with a practitioner is required in order to assure the best compensation of risk factors to adjust therapy; the factors being: hypertension, diabetes mellitus, hyperlipidemia; and in the group of patients under 50 was also performed examination of hypercoagulable state, particularly factor V Leiden and activated Protein C resistance. The ophthalmologic examination during the treatment period included the best corrected visual acuity, slit-lamp examination and fundoscopy, colour fundus photography, central retinal thickness (CRT) was measured with optical coherence tomography and fluorescein angiography. We were able to use the ...
Veins return oxygen-depleted blood back to the heart. The retina has one major artery and one major vein. The vein is called the central retinal vein.
Veins return oxygen-depleted blood back to the heart. The retina has one major artery and one major vein. The vein is called the central retinal vein.
Branch Retinal Vein Occlusion (BRVO) occurs when a small artery, hardened by age and/or high blood pressure compresses or squashes a retinal vein where they cross over. It usually affects only one eye. Vision may be blurred, distorted or obscured by intraocular bleeding.. Learn more ...
The Retina Center of New Jersey has Extensive Experience with Retina Clinical Research in many Clinical Areas Including Branch Retinal Vein Occlusion (BRVO) Research and Clinical Trials
Risk factors of branch retinal vein occlusion (BRVO) a study at tertiary care centre -IP Indexing is an indexing portal for citation of database covering scientific and scholarly Journals from all over the world. Our aim and objective to enhance visibility of your reputed articles and journals for use of researchers an
Chorioretinal venous anastomosis{ref47}{ref48}{ref49}{ref50}{ref51} is performed by creating an anastomosis to bypass the site of venous occlusion in the optic disc. In this procedure, retinal veins a... more
Chorioretinal venous anastomosis{ref47}{ref48}{ref49}{ref50}{ref51} is performed by creating an anastomosis to bypass the site of venous occlusion in the optic disc. In this procedure, retinal veins a... more
[86 Pages Report] Check for Discount on Retinal Vein Occlusion - Pipeline Review, H1 2016 report by Global Markets Direct. Global Markets Directs, Retinal Vein Occlusion - Pipeline...
An occlusion, or blockage, of a retinal vein is a common cause for vision loss. When the central vein becomes blocked, blood flow out of the eye is reduced. This leads to bleeding and swelling of the retina, a condition known as macular edema. Given the success of both Lucentis and Avastin in treating retinal fluid accumulation in wet macular degeneration, California Retina researchers set out to determine if these two drugs could be effective treatments for patients suffering from central retinal vein occlusions. California Retina Research Foundation began the studies in 2005 and results were presented at the Association for Research in Vision and Ophthalmologys annual meeting. Using the data from this small clinical trial, Genentech and investigators around the country initiated large scale national clinical trials to further evaluate the treatment of retinal swelling or macular edema associated with branch and central retinal vein occlusions using Lucentis. These trials were conducted at ...
Macular Oedema and Neovascular Glaucoma are the two main complications of Retinal Vein Occlusion. Laser Photocoagulation is offered in Bankstown NSW, Sydney.
Retinal vein occlusion (RVO) is a common vascular disorder of the retina and one of the most common causes of vision loss worldwide. Specifically, it is the second most common cause of blindness from retinal vascular disease after diabetic retinopathy.
Retinal vein occlusion is a condition where vein in the retinal circulation has become blocked. Dr Tim Isaacs offers eye treatments in Perth and Subiaco.
Retinal laser photocoagulation is an in-office procedure used to treat a number of retinal conditions, including retinal tears, diabetic retinopathy, macular edema and retinal vein occlusion. It is most frequently used to. read more ...
Retinal vein occlusion (RVO) is a disease that is often associated with a variety of systemic disorders including arterial hypertension, diabetes mellitus, dyslipidemia and systemic vasculitis. There
Retinal Vein Occlusion - An Eye Circulation Problem The retina is like a fine film that lines the back of your eye and it is the part of the eye that gives
Coastal Eye Institute is an eye center and eye doctor specializing in retinal vein occlusion and retina repairs. We have offices in Sarasota, Bradenton, Manatee, Lakewood Ranch, Ellenton, Parrish and Sun City Center.
Sudden loss of vision? Retinal vein occlusion may be the cause if you have high blood pressure. See our retinal specialist for a comprehensive examination.
Retinal Vein Occlusion information including symptoms, diagnosis, misdiagnosis, treatment, causes, patient stories, videos, forums, prevention, and prognosis.
Retinal Vein Occlusion Risk Factors Last postbymtbargeman « Fri Jul 18, 2008 6:22 pm ... Risk Factors for Retinal Veinal Occlusion Last postbymtbargeman « Fri Jul 18, 2008 6:19 pm ... Retinal Vasculitis Last postbyMike Bartolatz « Thu Mar 16, 2006 1:30 pm ...
central vein sign and iron in lesion as biomarkers Last post by frodo « Wed Sep 15, 2021 11:02 am Posted in Chronic ... Diagnosis via retinal inspection improved Last post by frodo « Mon May 31, 2021 3:27 am Posted in MS Etiology and Pathogenesis ... retinal thinning, cortical lesions, meningeal inflammation, lesions and brain atrophy are linked Last post by frodo « Fri Jun ... Association of retinal atrophy with cortical lesions and leptomeningeal enhancement in multiple sclerosis on 7T MRI Abstract. ...

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