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At least 1,747 records · Page 97Linked to original sources
PubMed1990

Age-related retinal changes--comparison between albino and pigmented rats.

To characterize aging as a factor responsible for structural changes the retinae of 47 Wistar-derived albino rats and 50 pigmented rats of the Norway and BDE (Han) strains between the ages of 1 and maximal 36 month were examined by light and electronmicroscopy and analysed for changes in cell densities. In all 3 rat strains there was an overall decline in nuclear densities of outer layer nuclei by 38 - 50% and inner layer nuclei by 27 - 33% between the ages of 1 and 27 months. Over the same age-range the ganglion cell loss was comparable to the decline in the inner nuclear layer. Neuronal cell death occurred at all ages and was more pronounced in albino rats. Moreover, in albino rats, cones were more resistant than rods to destruction by age and ambient light. Age-related ultrastructural changes in the retinal pigment epithelial cells (RPE) were in both pigmented strains: (1) a substantial accumulation of lipofuscin, (2) an apparent thickening of the basement membrane and (3) absent or greatly enlarged pleomorphic basal infoldings. In up to 27-month old BDE (Han) and 36-month old Norway rats besides mature stage IV-melanosomes also stage III-melanosomes can be observed. Characteristic of RPE-cells in old rats of these two strains were also compound granules and compound melanosomes. In peripheral RPE-cells of albino rats premelanosomes can be sporadically detected up to 31 months of age. Age-related changes in retinal vessels were found in the superficial and deep capillary network. The only finding was a 2-3 fold increase in thickness of the capillary basement membrane.

Aging↗
PubMed1981

[Anthocyanosides in the treatment of retinopathies (author's transl)].

Thirty-one patients with various types of retinopathy were investigated with regard to the effect of anthocyanosides on the retinal vessels. Especially in patients with diabetic retinopathy, a positive influence on the permeability and tendency to hemorrhage was observed. The importance of internal treatment of the primary disease is pointed out.

Adult↗
PubMed1979

Simulataneous occlusion of the central retinal artery and vein.

Combined CRAO/CRVO in our patients occurred with rapid visual loss, usually over a few hours, associated with evidence of inflammation and/or cellular infiltration of the retrobulbar portion of the optic nerve. The ophthalmoscopic appearance was characteristic, with papilledema and hemorrhages of various types in the posterior pole. The retina also showed ischemic changes, with a milky-white color and cherry-red macula. Fluorescein angiography, when possible, showed no retinal vascular flow, and normal choroidal flow. After six to eight weeks, optic atrophy was evident and the retinal vessels were markedly narrowed or obliterated. The macula showed typical cystic changes. Neovascularization often developed, leading to neovascular glaucoma as the end result.

Adult↗
PubMed1982

[Clinical and experimental results in the treatment of massive periretinal proliferation (MPP), a retinal detachment with a most unfavorable prognosis].

Today eyes with massive periretinal proliferation which are often seen after uncured retinal detachments or after perforating injuries can be cured at least in 25 to 35% of the cases, even with modern surgical techniques. This is due to proliferation of cells, which enter through different pathways--retinal tears, perforating wounds of sclera and chorioidea, damaged retina or retinal vessels--into the vitreous and form membranes, which prevent the retina to attach. In the vitreous gel these cells of different origin can transform into fibroblast-like or myofibroblast-like cells. They also behave in the same way like fibroblasts or myofibroblasts and cause a kind of excessive wound healing and scar formation in the vitreous cavity. With the use of modern vitreous techniques we could cure nearly 43% of 14 patients with MPP after uncured retinal detachments or after perforating injuries. Because mechanical removal of intravitreal and periretinal membranes alone turned out to be unsuccessful in nearly 60%, methods of medical therapy to suppress this cell-activity seemed to be rather needed. By animal experiment we tried to produce retinal detachments by transplantation of homologue fibroblasts into the vitreous cavity of rabbit eyes, and observed traction detachments in 55% of the eyes. Histologic examination showed a rapid change of loose, round fibroblasts into elongated cells with long nuclei, which formed strands and caused vasoproliferation, especially where the strand reached the rabbit retina. By means of autoradiography the peak of cell activity turned out to be in the 3rd week after cell-transplantation and further examinations of the optic disc showed, that the vascular endothelium cell might be one source of the proliferation. There was no difference between the number of eyes which developed retinal detachment in the aphakic eyes and in the lentectomized and vitrectomized eyes, but we observed the clinical appearance of MPP earlier and more pronounced in the lentectomized and vitrectomized eyes. In the last experiment we tried to inhibit intraocular proliferation with intravitreal dexamethasone alcohol. This leaded to a significant reduce of the number of experimental detachments and vasoproliferations.

Adolescent↗
PubMed1977

The ocular manifestations of Behçet's disease.

Of 32 patients with Behçet's disease, 21 had uveitis. The uveitis was seldom the initial manifestation of systemic disease, but once established, it tended to become chronic and bilateral, involving the anterior and posterior segments. Hypopyon was a relatively uncommon occurrence in this series. All patients with uveal inflammation had obvious cellular reactions within the vitreous body. Other posterior segment manifestations of the disease included localized retinal edema, macular edema, disc edema, retinal pigmentary changes, and accumulation of exudative material in the deep retina. One patient developed a necrotizing retinitis with deep retinal exudation and subsequent retinal detachment. Occlusions of retinal vessels were common. Neuro-ophthalmologic manifestations of Behçet's disease included cranial nerve palsies, a homonymous hemianopic field defect, and papillitis.

Adolescent↗
PubMedDate not supplied

[Therapy of fundus oculi vascular pathology by solcoseryl].

Long (for more than 17 years) therapy of 2331 patients (3122 eyes) with vascular conditions of the fundus oculi by a retinotropic drug solcoseryl showed its high efficacy as a monotherapy and in complex with other traditional and symptomatic treatments. Solcoseryl improved the visual function and hemodynamics of retinal vessels, promoted a more stable and longer stabilization of the treatment results, and accelerated the rehabilitation of patients.

Actihaemyl↗
PubMed1990

Müller cell changes precede vascularization of the pigment epithelium in the dystrophic rat retina.

In the Royal College of Surgeons rat with inherited retinal dystrophy, photoreceptor cell degeneration is accompanied by retinal pigment epithelial (RPE) cell alterations and Müller cell changes such as increased expression of glial fibrillary acidic protein (GFAP). Vascular changes such as vascularization of the RPE, vascular proliferation, and formation of vitreoretinal membranes (VRMs) are observed later. To study the relationship of Müller cell changes to the vascular alterations in the dystrophic retina, we used immunoperoxidase techniques and antibodies against GFAP and vimentin. Our study showed that during photoreceptor degeneration, Müller cells expressed small amounts of GFAP. As degeneration progressed, GFAP expression increased and morphological alterations occurred in Müller cells. Müller cell apical processes extended and proliferated in the subretinal space and contacted the apical surface of duplicated RPE cells. Later, GFAP reactive fibers surrounded retinal vessels apposed to the RPE. As the vessels became enmeshed within the RPE, the GFAP-positive perivascular processes disappeared. Eventually, the RPE-associated vessels became displaced into the inner retina where VRMs were sometimes observed. Immunoblots showed increased GFAP in dystrophic as compared with control retinas. Studies of vimentin distribution in the dystrophic retina showed results similar to the GFAP study. Moreover, the vimentin study suggested increased number of Müller cell processes in the dystrophic as compared with control retinas. The close temporal and anatomical relationships among Müller cell, RPE, and vascular changes in the dystrophic rat suggest a role for Müller cells in retinal neovascularization and proliferative retinopathy.

Animals↗
PubMedDate not supplied

[Retinal vascular lesions in systemic lupus erythematosus and secondary antiphospholipid syndrome].

The study was undertaken to determine a possible association of retinal vascular lesion in systemic lupus erythematosus (SLE) with the antiphospholipid syndrome (APS). A hundred and ninety-four patients (160 females and 34 males, whose mean age was 30.7+/-8.9 years) with verified SLE were examined. Group I comprised 67 patients with retinal vascular lesions (Subgroup la (n = 13) with retinal vascular occlusions and Subgroup 1b (n = 54) without occlusions). Group 2 included 127 patients without retinal vascular lesions. APS was detected in 86 patients. Retinal vascular occlusions more frequently occurred in patients with APS (13.9%) than in those without APS (0.9%) (p = 0.0009) and more frequently in patients with APS and thrombocytopenia (24.3%) than in those with APS without thrombocytopenia (6.1%) (p = 0.0359). Extraocular thromboses were more frequently encountered in Subgroup 1a (69.2%) than in Subgroup 1b (33.3%) (p = 0.0399) and in Group 2 (22.8%), (p = 0.0010). Cerebral circulatory disorder (CCD) was observed in 30.7% in Subgroup la, in 14.8% in Subgroup 1b, and in 7.9% in Group 2 (p = 0.0268). Transient ischemic attack (TIA) occurred in 46.2% in Subgroup la, in 24.1% in Subgroup 2a, and in 14.9% in Group 2 (p = 0.0129). Thrombocytopenia was identified in 69.2% in Subgroup 1a, in 22.2% in Subgroup 2a (p = 0.0021), and in 12.6% in Group 2 (p < 0.0000). The frequency of elevated IgG of anticadiolipin (aCL) in Subgroup 1a (80%) exceeded that in Subgroup 1b (37.9%) (p = 0.0309) and Group 2 (30.7%) (p = 0.0096). Another isotype of aCL (IgM 80%) was observed in patients with retinal vascular occlusions, but the differences in this index were insignificant in the groups and subgroups. The association of pathological changes in retinal vessels in the presence of lupus anticoagulant (LA) was particularly noticeable (91.7 and 52% in Subgroup la and Subgroup 1b, respectively (p = 0.0191) and 47.1% in Group 2 (p = 0.0088). There was an association of amaurosis fugax with eyeground occlusions (p < 0.004), CCD and TIA (p < 0.0002), APS (p < 0.0003), and essential hypertension (p < 0.05). Thus, occlusive lesions in the fundus of the eye are a common manifestation of thrombogenesis in SLE in the presence of APS. The frequency of concomitance of retinal vascular occlusions with cerebral circulatory disorders should be referred to as severe manifestations of SLE. Amaurosis fugas is a manifestation of retinal vascular lesion and associated with the presence of APS and elevated blood pressure in patients with SLE. There is an association of an occlusive process in the fundus of the eye with different symptoms of APS and primarily with IgG of aCL, LA, and thrombocytopenia.

Adult↗
PubMed1999

Morphological variations of the peripapillary circle of Zinn-Haller by flat section.

AIMS: To evaluate the morphometric and morphological variations of the circle of Zinn-Haller (CZH) in the human eye. METHODS: 42 human enucleated eyes were used in this study. After transverse flat thick sections were cut through the optic nerve and adjacent sclera, tissue sections were stained with haematoxylin and eosin or examined immediately by wet preparation under a light microscope. The average vessel diameter of the arterial circle and the average distance between the optic nerve head (ONH) and the arterial circle were determined. Various branching patterns of the CZH were also evaluated. RESULTS: The vessel diameter of the arterial circle was 123 (SD 75) microm (range 20-230 microm). The distance of the CZH from the ONH margin was 403 (352) microm (0-1050 microm). The CZH gave off branches to the optic nerve and to the peripapillary choroid (PPC) with various branching patterns especially at the entry point of paraoptic short posterior ciliary artery. CONCLUSIONS: The CZH exists within a variable distance from the ONH and its average diameter is similar to that of the central retinal vessels though it shows marked variation even in the same circle. The CZH also shows variable configurations in branching patterns. These variations may act as contributing factors that are responsible for the individual susceptibility of the anterior optic nerve and the PPC to circulatory disturbances.

Adult↗
PubMed1993

Isolation and culture of retinal microglia.

In the Royal College of Surgeons rat, the migration of phagocytic cells into the subretinal space accompanies photoreceptor cell death during the early stages of retinal dystrophy. These are followed closely by cellular alterations in the retinal pigment epithelium, Müller cells, and outer retinal vessels. We have identified the phagocytic cells as microglia and hypothesized that they may be involved in the above cellular changes. Thus, we developed procedures for their isolation and growth. Our study shows that retina-derived microglia (1) are positive for microglial markers Griffonia simplicifolia isolectin B4, Mac-1 alpha, phosphotyrosine, and vimentin; (2) are highly phagocytic; and (3) respond to macrophage colony stimulating factor by proliferating. This culture system would provide a valuable tool in studying mechanisms of cellular alterations in retinal disease.

Animals↗
PubMed1993

[Results of laser coagulation of retinal branch vein occlusions].

BACKGROUND: The benefit of laser treatment in patients with branch retinal vein occlusion (BRVO) is established in the literature. We investigated the relationship of morphological and fluorescein angiographic findings with the results of laser treatment. PATIENTS AND METHODS: Of 211 examined patients with BRVO argon-laser coagulation was performed in 121 (57%). Laser treatment was done in all patients with preretinal neovascularization and in patients with macular edema 3 months or more after the onset of occlusion with visual acuity < or = 20/40. Follow up examinations were performed in 3 months intervals with the last examination 11.7 months on average after treatment. Statistical analysis was done by Wilcoxon-test. RESULTS: Mean visual acuity before laser coagulation was 20/60, after laser treatment 20/50. Visual acuity in all patients improved significantly after laser treatment (p = 0.0001). A significant improvement occurred when treatment was performed within 3 to 4 months after onset (p < 0.0001), in patients with macular edema in the ischemic (p = 0.0005) and non ischemic type (p = 0.036), in patients without preretinal neovascularization (p < 0.0001) and without vitreous hemorrhage (p = 0.0001), in patients between 51 and 60 years (p = 0.0001) and between 41 and 50 years of age (p = 0.0086), in vein occlusions with intraretinal hemorrhages ++ (p = 0.0001), with hard exsudates + (p = 0.0047) in vein occlusions of the temporal superior (p = 0.0016) and the temporal inferior branch (p = 0.028) and in patients with diffuse dye leakage + (p = 0.0036) and ++ (p = 0.007). No significant visual improvement was found in patients with ischemic maculopathy, hard exsudates ++, preretinal neovascularization and vitreous hemorrhage, diffuse intraretinal dye leakage , dye leakage ++ and from retinal vessels and in patients < or = 40 and > 60 years of age. CONCLUSIONS: Laser treatment in BRVO according to the criteria of the study is beneficial and results in significant visual improvement.

Adult↗
PubMed1993

Photochemically-induced lesion of the rat retina: a quantitative model for the evaluation of ischemia-induced retinal damage.

The effects of ischemia-induced retinal damage were quantitatively evaluated in rats with the aim of obtaining a suitable model to study the pathogenesis of the loss of retinal neurons after ischemic episodes. Anaesthetized rats were injected with 80 mg/kg i.v. of the fluorescein rose bengal dye and one eye was exposed to cold light for different periods (from 5 to 30 min). The animals were sacrificed at different times (1 and 4 hr; 2 and 7 days) after the lesion and the photochemically-induced damage was evaluated. The damaged retinae appeared thicker, numerous neurons of the inner nuclear layers showed swelling of the perinuclear cytoplasm and the retinal vessels were enlarged. The activity of choline acetyltransferase (ChAT) and glutamic acid decarboxylase (GAD), two marker enzymes of the GABAergic and cholinergic neurons, significantly decreased, indicating a degeneration of GABAergic and cholinergic amacrine cells.

Animals↗
PubMed1995

Neuronal ceroid lipofuscinosis in the Polish Owczarek Nizinny (PON) dog. A retinal study.

Visual dysfunction and neurological symptoms were found in Polish Owczarek Nizinny (PON) dogs. Two dogs were examined, one at 2 years of age and the other one at 4 years. The oldest dog was totally blind. The 2-year-old dog developed mental disturbances and the 4-year-old dog became severely ataxic. Ophthalmoscopical findings were retinal hyper-reflectivity, attenuation of the retinal vessels and the presence of greyish to brown spots in the fundus. Electrophysiological and ultrastructural studies were performed in the 2-year-old dog. Scotopic ERG responses were absent, whereas 30 Hz cone flicker responses were recordable, although with an amplitude reduced to about 30% of the normal level. A slow negative potential replaced the c-wave, indicating a dysfunction of the RPE. Intracellular inclusions with a granular appearance or containing membranous fingerprint-like or curvilinear profiles, resembling ceroid, were found in different retinal cells. The RPE cells in the central areas were charged with autofluorescent material having similar structure, Photoreceptor degeneration was most severe in the central areas, corresponding to the RPE changes. It appears than the PON dog may provide a new animal model for neuronal ceroid lipofuscinosis.

Animals↗
PubMed1993

Clinicopathology of a case with retinopathy of pancreatitis.

Bilateral retinopathy of pancreatitis developed in a 36-year-old male patient during recurrent acute necrotizing pancreatitis. The retinopathy remained clinically unchanged between the detection and the death 6 days later. Characteristics of the retinal lesions were histologically similar to cotton-wool spots of other origin, but all the retinal vessels including vessels around and in the cotton-wool spots were intact and contained plasma and red blood cells. Absence of vascular occlusion and endothelial damage suggests that in acute pancreatitis vascular embolisation in the retina is not necessary to the development of cotton-wool patches.

Acute Disease↗
PubMed1993

Aldose reductase inhibition fails to prevent retinopathy in diabetic and galactosemic dogs.

To investigate a possible role of excessive polyol production in the pathogenesis of diabetic retinopathy, 16 ALX-induced diabetic dogs and 20 experimentally galactosemic dogs were randomly assigned to 5 yr of treatment with either sorbinil, an aldose reductase inhibitor, or a placebo. The severity of hyperglycemia in sorbinil-treated and placebo groups was monitored throughout the 5-yr study by assay of glycosuria and nonenzymatically glycated plasma protein and HbA1 needed in an effort to avoid confounding possible group differences in hyperglycemia severity with possible drug effects. Inhibition of polyol production by sorbinil was monitored in erythrocytes throughout the study and also in retina and other tissue obtained at autopsy. Trypsin digests of retinal vessels were compared after 60 mo of diabetes and after 42 and 60 mo of galactosemia. In diabetic dogs, development of retinopathy was not significantly influenced by a sorbinil dose (20 mg.kg-1 x day-1) sufficient to prevent elevation of sorbitol levels in retina and other tissue. Likewise, in dogs made experimentally galactosemic for 42-60 mo, administration of sorbinil (60-80 mg.kg-1 x day-1) had no significant effect on the development of retinopathy notwithstanding prevention of 93-96% of the polyol elevation in retina and other tissue. Retinal capillary basement membrane was significantly thicker than normal in diabetic and in galactosemic dogs and was not significantly influenced by administration of sorbinil in either dog model. Thus, no evidence was found that the development of retinopathy is critically dependent on excessive polyol production or accumulation.

Aldehyde Reductase↗
PubMed2002

[A case report of unusual retinal findings in a patient with Zieve syndrome].

BACKGROUND: The Zieve syndrome is characterized by hemolytic anemia in conjunction with secondary hyperlipidemia in patients suffering from alcohol-related toxic liver damage. So far no retinal changes have been reported due to the Zieve syndrome. CASE REPORT: A 44-year-old diabetic attended a routine control by an ophthalmologist. It was known that he had steatohepatitis due to an abuse of ethanol for years and 1 month previously he had suffered from nausea and vomiting. The visual acuity was found to be good on both sides (1.0/0.8). In the fundus white-colored retinal vessels and peripapillary cotton wool exsudates with isolated hemorrhages were found. An extremely lipemic serum and a severe anemia were present. The patient was referred to the internal department for further investigation and because of the anemia the patient received two blood transfusions. The elevated cholesterol and triglyceride levels in the serum could be substantially reduced by treatment with a cholesterin synthetase inhibitor and a fibrate. The follow-up examination 3 weeks later revealed a regular blood flow and a regression of cotton wool exsudates and 1 month later no pathological retinal findings were detected. CONCLUSIONS: The retinal changes were caused by the combination of severe anemia and hyperlipidemia and these findings played a leading role for deciding further diagnostic procedures. After treatment of the metabolic disorder the retinal changes were completely reversible without functional restrictions.

Adult↗