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Cancer-associated retinopathy with presumed vasculitis.

PURPOSE: To treat a 63-year-old woman who experienced fairly rapid vision loss in association with small-cell carcinoma of the lung. METHODS: She underwent a full ophthalmologic examination, including fluorescein angiography and an immunologic study by Western blot analysis. RESULTS: Fluorescein angiography demonstrated diffuse staining of the retinal vessels. She had 62-kd antiretinal antibody in her serum. Cancer-associated retinopathy was diagnosed. CONCLUSION: The staining seen on the angiogram appears to indicate vasculitis, which would cause the characteristic attenuation of retinal vessels in this disease.

Anti-Inflammatory Agents↗

Two cases of unilateral retinal neovascularization in Turner syndrome.

PURPOSE: To report two cases of unilateral retinal neovascularization in Turner syndrome. METHOD: We examined two female infants, born at 34 weeks' and 33 weeks' gestation, who had received oxygen for 9 days and 3 days, respectively, after birth. Both infants had the 45,XO karyotype of Turner syndrome. RESULTS: In each patient, the fundus of one eye showed an avascular area, neovascularization, and multiple branchings with anastomosis of retinal vessels in the temporal periphery. Fellow eyes showed no abnormalities in the fundi. Both infants were treated with argon laser photocoagulation to the avascular area and the neovascularization in the temporal periphery. The neovascularization regressed completely after retinal photocoagulation. CONCLUSION: Abnormalities of retinal vessels may be one of the ocular findings associated with Turner syndrome.

Female↗

Effects of buphenine (nylidrin) on the perfused mammalian eye.

Buphenine (nylidrin), a beta-adrenergic agonist, is used therapeutically for its vasodilating effect on the peripheral circulation and possibly on the cerebral circulation as well. In spite of its ophthalmic usage in degenerative retinal disease and glaucoma, buphenine's ocular effects and their mechanisms are not sufficiently established. Consequently, we studied the action of 4.5-120 microM buphenine in isolated, arterially perfused cat eyes, and then used light-evoked electrical signals, perfusion flow rates and the diameters of the retinal vessels as parameters for the drug's effect. Our findings showed that buphenine induced a marked, dose-related, reversible increase in the amplitude of the electroretinogram (ERG) b-wave, a decrease in the c-wave, but no significant changes in the standing potential and light peak of the DC-ERG. The compound action potential of the optic nerve revealed dose-dependent and reversible changes in configuration. However, the flow of perfusate was not affected by the drug, and the diameter of retinal vessels did not change significantly. Our studies suggest that the interaction of buphenine with retinal adrenergic receptors is not related to the vasculature present but to elements involved in information processing. It is likely that these receptors are linked to neurons, since the beta-agonist affected the ERG b-waves as well as the compound action potential of the optic nerve.

Adrenergic beta-Antagonists↗

[Therapy of arterial vascular occlusions of retinal and optic nerve (author's transl)].

The authors report on 136 cases of arterial occlusion (80 patients suffering from occlusion of the retinal vessels and 56 patients with vascular occlusion in the optic nerve) who were treated with the vasoactive xanthic substance Pentoxifylline (Trental). A part from its positive effect on the vascular circulation, Trental also helps to improve microcirculation in the retinal and optic nerve tissue damaged by hypoxia. After a 2-week infusion therapy with additional digitalisation, treatment was continued for another 3-6 months with oral administration of Trental 400. In 50 cases therapy was combined with the systemic administration of corticosteroids. Under the mentioned therapy a definitely improved visual acuity (at least 3 lines on the eye charts) was achieved in 56% of the cases with occlusion of the retinal vessels and in 51% of the cases with vascular occlusion in the optic nerve, i.e., in 54% of the total number of patients. Whether or not the additional administration of corticosteroids helped to this effect was not proved.

Administration, Oral↗

[Risk factors for age-related macular degeneration].

PURPOSE: To present the results of examinations of the risk factors for age-related macular degeneration (AMD) carried out in the last 3 years. MATERIAL AND METHODS: Our clinical material comprised 119 patients, 69 women and 50 men, aged 43-85, mean age 70 years. Using classification according to the worse eye, there were 20 patients with drusen, 27 with atrophic changes and 72 with exudative form and AMD. The following risk factors were evaluated: age, sex, body mass index, history of general medical conditions, cigarette smoking, sun exposure, family history of AMD and ocular conditions such as iris color, lens opacities, hyperopia, gerontoxon and changes in retinal vessels. RESULTS: The significant relationships were found between the development of AMD and the age of patients, as well as between the advanced forms of AMD and the history of cardiovascular diseases and sclerotic changes in retinal vessels, 87% of examined patients have light iris and 52% body mass index above 26. CONCLUSIONS: The studies confirmed the role of age in the development of AMD and indicated cardiovascular disturbances, increased body mass index and light iris as the possible risk factors for AMD that are most worth further studying. The special attention should be also paid to drusen as the risk factor of AMD.

Adult↗

Endothelin-1 impairs retrograde axonal transport and leads to axonal injury in rat optic nerve.

The purpose of this study was to examine the effects of endothelin-1 (ET-1) on retrograde axonal transport in the rat optic nerve. Vehicle or ET-1 (0.2, 1, or 5 pmol/eye) were injected into the vitreous body in Sprague-Dawley rats. Retinal vessels were observed, using a fundus camera, before, and at 10 min, 3 days and 7 days after a single intravitreous injection. Two days after the injection, a neuronal tracer, fluoro gold, was administered via the superior colliculi to retrogradely label active retinal ganglion cells (RGCs). Five days after the tracer administration, retrogradely labeled RGCs were evaluated in the flat-mounted retina, and cross sections from each optic nerve were graded for injury by four independent, masked observers. ET-1 at 5 pmol/eye caused a significant constriction of retinal vessels (versus the vehicle-treated group) at 10 min after the injection. Intravitreous injection of ET-1 caused a dose-related decrease in the number of retrogradely labeled RGCs. Injection of 5 pmol/eye ET-1 led to a statistically significant decrease in the number of retrogradely labeled RGCs (versus the vehicle-treated group). ET-1 at 1 and 5 pmol/eye caused histological optic nerve damage (evaluated using a graded scale). The histological optic nerve damage correlated with the number of retrogradely labeled RGCs. In conclusion, a single intravitreous injection of ET-1 impaired retrograde axonal transport in the rat optic nerve and this impairment correlated with the histological optic nerve damage.

Animals↗

Localization of blood-retinal barrier breakdown in human pathologic specimens by immunohistochemical staining for albumin.

Human pathologic specimens from eyes with several different disease processes were immunohistochemically stained with antisera directed against rat or human serum albumin. In 33 eyes with no known ocular disease and no pathologic abnormalities, positivity was seen in the choroid and within retinal vessels, but not within the retina, except in one case in which focal staining in an area of outer retina was noted. In eyes with a history of ocular disease and/or pathologic findings, extravascular albumin staining was seen in areas of the retina generally corresponding to pathologic abnormalities. Albumin in the inner retina appeared to emanate from retinal vessels, but often collected along the internal limiting membrane. Staining in the outer retina was frequently demonstrated along the external limiting membrane, but in some cases, was also seen between the photoreceptor outer segments and within the retinal pigment epithelium. Eyes with primary retinovascular disease showed staining more commonly in the inner retina (77%) than the outer retina (38%) as would be predicted on theoretical grounds, whereas eyes with other disease processes showed no difference in frequency of staining between inner and outer retina. These data suggest that immunohistochemical staining of extravascular albumin is a useful technique for localizing breakdown of the blood-retinal barrier and is applicable to several disease processes.

Blood-Retinal Barrier↗

Macroglial and retinal changes in hypercholesterolemic rabbits after normalization of cholesterol levels.

This study evaluates hypercholesterolemic rabbits, examining the retinal changes in Müller cells and astrocytes as well as their variations after a period of normal blood-cholesterol values induced by a standard diet. New Zealand rabbits were divided into three groups: G0, fed a standard diet; G1A, fed a 0.5% cholesterol-enriched diet for 8 months; and G1B, fed as G1A followed by standard diet for 6 months. Eyes were processed for transmission electron microscopy and immunohistochemistry (GFAP). While G1B resembled G0 more than did G1A, they shared alterations with G1A: a) as in G1A, Müller cells were GFAP+, filled spaces left by axonal degeneration, formed glial scars and their nuclei were displaced to the nerve-fibre layer. The area occupied by the astrocytes associated with the nerve-fibre bundles (AANFB) and by perivascular astrocytes (PVA) in G1A and G1B was significantly lower than in controls. However, no significant differences in PVA were found between G1A and G1B. In G1B, type I PVA was absent and replaced by hypertrophic type II cells; b) Bruch's membrane (BM) was thinner in G1B than in G1A; c) the retinal pigment epithelium (RPE) cytoplasm contained fewer lipids in G1B than in G1A; d) in G1A and G1B choriocapillaris and retinal vessel showed alterations with respect to G0; e) cell death and axonal degeneration in the retina were similar in G1A and G1B. The substitution of a hyperlipemic diet by a standard one normalizes blood-lipid levels. However, the persistence of damage at retinal vessels and BM-RPE could trigger chronic ischemia.

Animals↗

Improvement of reproducibility of macular volume measurements using the Heidelberg retinal tomograph.

AIMS: To develop a more reproducible method of macular volumetric analysis in order to facilitate serial monitoring of changes in retinal oedema with time. METHODS: The Heidelberg retinal tomography (HRT) machine was used to scan the macula of 20 normal subjects and 40 diabetics with macular oedema. The volume above reference plane (VARP) within a 2 mm diameter and 3 mm diameter circle was measured twice in each eye. The position of the circle to be measured was carefully defined relative to major retinal vessels. As a modification to the previously published technique, fluctuation of the height of the contour line relative to the focal plane of the eye is compensated for by an adjustment of the reference plane. The position of the circle was controlled relative to major retinal vessels using an acetate. The reproducibility of VARP measurement was assessed by three variables-the standard error of the difference on two isolated VARP measurements, the standard error of the difference between the average of three readings on two different occasions, as well as the coefficient of variation (COV). RESULTS: Both the 2 mm and 3 mm circles showed good reproducibility in VARP measurements. In normal subjects, the COV of VARP for 2 mm circles and 3 mm circles were 13% and 12% respectively. In patients with macular oedema, the COV of VARP for 2 mm circles and 3 mm circles were 9% and 11% respectively. CONCLUSION: The modification of VARP measurements between scans of the same eye has improved the COV from 31% to 9% in eyes with diabetic macular oedema.

Diabetic Retinopathy↗

Alteration of the blood-retina barriers in cases of viral retinitis.

This paper presents three cases of serologically documented viral retinitis, and the great value of fluorescein angiography in outlining the structural abnormalities and the site of the lesions. Of our series in the case of influenza retinitis, the fluoroangiographic findings showed dye leakage from retinal vessels in the posterior pole. The dye leakage did not appear completely in the sites of macular edema. This edema was similar to the clinical appearance of cotton-wool spots and was arranged in a star-like pattern. One of the cases of cytomegalovirus retinitis (Case 3), a previously healthy adult with dysfunction of the cellular immune system, seems to be a further example of an inflammation in the inner retina presenting cotton-wool spots at the early stage. Case 2, a previously healthy adult, fulfilled the criteria for Vogt-Koyanagi-Harada syndrome. The patient had serologically documented cytomegalovirus infection with dysfunction of the cellular immune system. The fluorescein angiographic examination showed alteration both in the inner and outer blood-retina barriers as it is characteristic in cases of Harada syndrome. The cytomegalovirus infection might be assumed to play a role in the clinical picture as well as in the etiology of this disease.

Adult↗

[Pseudoangiitis in bilateral ocular ischemia].

BACKGROUND: The term 'frosted branch angiitis' was initially used to describe an idiopathic form of vasculitis in association with panuveitis. It has since also been used to describe the angiographic phenomenon of diffuse leakage along retinal vessels against the background of other ocular and systemic diseases. METHODS: We describe a 57-year-old male patient with acute bilateral reduction of visual acuity, headaches and absence of any pulse at the temporal arteries. Fluorescence angiography showed bilateral diffuse leakage along all the retinal vessels, which resembled frosted branches. Laboratory parameters and histology were not indicative of vasculitis. Imaging showed complete occlusion of both common carotid arteries and a hypoplastic vertebral artery on the left. CONCLUSIONS: Ocular ischemia may imitate primarily inflammatory conditions in its angiographic appearance.

Angiography↗

Inhibitory effect of bucillamine on the increased leukocyte entrapment in the retinal microcirculation of diabetic rats.

PURPOSE: To evaluate quantitatively the effects of bucillamine on the entrapment of leukocytes in the retinal microcirculation of diabetic rats. METHODS: 13 male Brown Norway rats were injected with streptozotocin (STZ). After the animals developed diabetes, they were divided into two groups. Group 1 (n=7) received fresh drinking water without bucillamine, and group 2 (n=6) received fresh drinking water supplemented with bucillamine (200 mg/kg per day). Rats that were not injected with STZ and received water without bucillamine served as controls (n=6). Four weeks after the injection of STZ, the leukocytes in the retina were observed by acridine orange digital fluorography. The number of leukocytes trapped in the retinal vessels was compared among the three groups. RESULTS: In the untreated diabetic rats, the number of trapped leukocytes was significantly higher than in control rats or bucillamine-treated diabetic rats (P<0.05). CONCLUSIONS: We demonstrated an inhibitory effect of bucillamine on leukocyte entrapment in the retinal vessels of diabetic rats. Bucillamine may have therapeutic efficacy in preventing the development of diabetic retinopathy.

Animals↗

Ocular blood flow velocities in patients with proliferative diabetic retinopathy and healthy volunteers: a prospective study.

BACKGROUND: Diabetes affects the vascular ocular circulation. Colour Doppler imaging allows for simultaneous two dimensional anatomical imaging and Doppler evaluation of blood flow velocity; with this technique ocular blood flow velocity can be evaluated in normal and diabetic patients. METHODS: A prospective study compared blood flow velocity in ocular vessels (ophthalmic artery, posterior ciliary arteries, central retinal vessels, and vortex veins) of 25 patients with proliferative diabetic retinopathy and 30 age matched normal subjects using a colour Doppler imaging unit (Toshiba Sonolayer SSA-270 A with a 5.0 MHz PLF-503 ST phased array scanning head). RESULTS: The diabetic patients had lower blood velocities than the volunteers. There were significant differences in ophthalmic artery; systolic (p < 0.01), diastolic (p < 0.001), mean velocity (p < 0.05), and central retinal artery; systolic (p < 0.001), diastolic (p < 0.001), mean velocity (p < 0.05). No significant correlations were found between age and blood velocities. CONCLUSION: Ocular blood flow velocity was decreased in diabetic patients with proliferative diabetic retinopathy.

Adult↗

Talc emboli and macular ischemia in intravenous drug abuse.

A patient with decreased visual acuity had small, glistening white particles that were scattered over both posterior poles. Monochromatic fundus photography revealed ghost vessels and intraluminal particulate matter in small retinal vessels. Fluorescein angiography demonstrated nonperfusion of small arterioles and macular capillaries. The patient admitted to multiple intravenous injections of crushed methylphenidate (Ritalin) hydrochloride tablets, which contain talc 18 months prior to examination. To our knowledge, visual loss and irreversible macular ischemia from talc emboli have not been previously documented.

Adult↗

Redefining papillorenal syndrome: an underdiagnosed cause of ocular and renal morbidity.

PURPOSE: To report ocular and renal findings specific to the inheritable entity called papillorenal (also known as renal-coloboma) syndrome and relate these to a common cause. DESIGN: Observational case series and genetic study. PARTICIPANTS: Two unrelated probands presenting with absent central retinal vessels and 11 available family members. TESTING: Doppler ultrasonographic imaging of the optic nerves and kidneys, fluorescein angiography, and genetic testing for PAX2 mutations were performed. In selected cases, indocyanine green angiography, scanning laser ophthalmoscope perimetry, Retinal Thickness Analyzer measurements, visual evoked potentials, and magnetic resonance imaging were also performed. MAIN OUTCOME MEASURES: Better defined characteristics of the papillorenal syndrome. RESULTS: Numerous cilioretinal vessels were present with rudimentary or absent central retinal vessels. Superonasal visual field defects, typical for papillorenal syndrome, corresponded to inferotemporal areas of anomalous retinal and choroidal perfusion and hypoplastic retina. Renal hypoplasia was discovered in two affected members of one family (with previously unsuspected renal failure in one case), and recurrent pyelonephritis was discovered in four affected members of the other family. No PAX2 mutations were detected. CONCLUSIONS: In the papillorenal syndrome, the hereditary absence of central retinal vessels may be missed, leading to confusion with isolated coloboma, low-tension glaucoma, and morning glory anomaly. Greater awareness of this syndrome will avoid unneeded glaucoma therapy, allow earlier recognition of renal diseases, and allow genetic counseling. We propose that the papillorenal syndrome is a primary dysgenesis that causes vascular abnormalities predominantly affecting the eye, kidney, and urinary tract, leading to hypoplasia of these structures. The absence of defects in the PAX2 gene in these families suggests that mutations in other genes may also be responsible for this syndrome.

Adult↗

Intermittent pressure augmentation during retrograde cerebral perfusion under moderate hypothermia provides adequate neuroprotection: an experimental study.

OBJECTIVE: For cerebral protection during aortic surgery, we introduced a novel retrograde cerebral perfusion method with intermittent pressure augmentation. We then assessed whether this novel method provides benefits similar to those provided by antegrade selective cerebral perfusion. METHODS: Eighteen dogs were randomly divided into 3 groups: the RCP-INT group, intermittent-retrograde cerebral perfusion at 15 mm Hg with intermittent pressure augmentation to 45 mm Hg (n = 6); the ASCP group, antegrade selective cerebral perfusion at a flow rate of 10 mL x kg(-1) x min(-1) (n = 6); and the sham group, no circulatory arrest (n = 6). Cooling (26 degrees C) with cardiopulmonary bypass and 60 minutes of circulatory arrest were performed in the RCP-INT and ASCP groups. The levels of tau protein in the cerebrospinal fluid and the diameters of the retinal vessels were measured. The neurologic deficit scores and the histopathologic damage scores of the brains were determined. RESULTS: The total postoperative tau protein levels (calculated as the area under the curve) did not differ significantly between the RCP-INT and ASCP groups (203 +/- 87 pg x mL(-1) x h vs 154 +/- 69 pg x mL(-1) x h, P = .95). The retinal vessels were effectively dilated at an augmented pressure of 45 mm Hg in the RCP-INT group. The total neurologic deficit score (0 = normal, 500 = brain death) and histopathologic damage score (0 = normal, 40 = worst) were not significantly different between the RCP-INT and ASCP groups (neurologic deficit score: 75 +/- 21 vs 70 +/- 21, P = .98; histopathologic damage score: 13.5 +/- 1.5 vs 14.2 +/- 1.3, P = .84). CONCLUSIONS: Intermittent augmented pressure dilated the cerebral vessels, allowing adequate blood supply without injuring the brain. This retrograde cerebral perfusion method provides adequate neuroprotection during moderate hypothermia.

Animals↗

Oxygen-induced retinopathy in newborn rats: effects of prolonged normobaric and hyperbaric oxygen supplementation.

An experimental study was conducted to verify the effects of prolonged normobaric and hyperbaric oxygen supplementation on retinal vessels in newborn animals. Nine litters of newborn Wistar rats were used in the following way. Two litters were used as controls. Two other litters received normobaric oxygen supplementation (FiO2 80%) for five days after birth. These rats were then removed and kept for five more days in room air. Retinopathy with marked peripheral retinal neovascularization was seen in these litters. Three other litters were exposed to the same treatment for ten days after birth, removed from oxygen, and kept for 15 more days in room air. Severe retinopathy with extraretinal proliferation and, in some cases, retinal detachment developed in these animals. Two other litters received hyperbaric (1.80 atm) oxygen supplementation (FiO2 80%) for ten days after birth and were then kept for 15 days in normobaric room air. These animals showed no evidence of peripheral retinopathy. It is possible that moderate hyperbarism exerts, in the newborn rat, a protective action against the toxic effects of oxygen supplementation on immature retinal vessels.

Animals↗