Decrease of diffusion of glycosylated albumin in retinal microcirculation by peptide fraction from bovine factor VIII.

The diffusion of the glycosylated albumin in the retinal vascular system has been studied in male New Zealand rabbits, using fluorangiographic techniques. A first group of animals was treated for 15 days with the peptide fraction from bovine Factor VIII (Vueffe); a second group, used as control group, was treated with physiological solution. At the end of treatment, glycosylated albumin was made fluorescent and then injected into the marginal vein of the rabbit. The direct observation and the photometric measurements performed on the digitized photograms with an image processing system showed a considerable reduction in retinic capillary diffusion of glycosylated albumin in the animals treated with the peptide fraction. The substance used in the study might therefore be of importance in the treatment of systemic disease with retinic vascular damage.

Idiopathic subretinal neovascularization.

Idiopathic subretinal neovascularization is a potentially blinding condition and often strikes patients in their prime of life. It appears to be seen in more females, at an earlier age than males. Treatment is possible by photoablation of the subretinal new vessel by Argon or Yag laser. There is a clinical impression that Argon laser is more effective than the Yag laser for this purpose.

Differential regulation of protein kinase C and (Na,K)-adenosine triphosphatase activities by elevated glucose levels in retinal capillary endothelial cells.

Elevated cellular sorbitol levels resulting from conversion of increased glucose by aldose reductase might deplete cellular myoinositol content, which could then lower inositol phosphates (InsPs) and diacylglycerol levels, key regulators of protein kinase C (PKC). Secondary to altered PKC activity, other cellular enzymes such as (Na,K)-ATPase could be affected. To test this hypothesis we examined the association between PKC activity, (Na,K)-ATPase activity, and sorbitol, myoinositol, and InsP levels in cultured bovine retinal capillary endothelial cells, a cell type prominently involved in diabetic retinopathy. Elevating glucose concentration in culture media from 100 to 400 mg/dl led to a 100% increase in sorbitol levels, which could be inhibited completely by sorbinil, an aldose reductase inhibitor. In contrast, no changes were observed in myoinositol or InsP levels. Subfractionated PKC activities showed a 100% increase in the membranous pool with a parallel decrease in the cytosolic fraction. Adding sorbinil did not affect PKC activity, whereas the PKC agonist, phorbol myristate acetate (PMA), stimulated translocation of PKC. Ouabain-inhibitable (Na,K)-ATPase activity was decreased 70% by elevated glucose levels. This decrease could be prevented by adding either PMA or sorbinil. Thus, in retinal capillary endothelial cells elevated glucose concentration can affect PKC and (Na,K)-ATPase activities, probably via different mechanisms.

Efficacy of panretinal photocoagulation in central retinal vein occlusion.

This retrospective study reviews the efficacy of panretinal photocoagulation in the prevention and management of ocular neovascularization in 55 cases of central retinal vein occlusion. Differentiation of occlusions into ischemic and nonischemic forms is of critical importance, with aggressive laser treatment being warranted in the ischemic variety. The presence of ocular neovascularization may not necessarily imply a grim prognosis.

Pseudotumor cerebri and macular disease.

The most common indications for treatment of patients with pseudotumor cerebri are the presence of severe intractable headaches and evidence of optic neuropathy. The role of the ophthalmologist in following patients with pseudotumor cerebri has been to document optic nerve dysfunction in terms of visual field abnormalities or loss of visual acuity. Macular changes have been described in association with papilledema. A case of pseudotumor cerebri and associated macular disease is reviewed to call attention to the need for the ophthalmologist to differentiate between visual loss secondary to optic neuropathy from that of macular disease. The case illustrates how quickly macular disease can develop. The management of patients with pseudotumor cerebri is discussed.

Pigmentary retinal dystrophy associated with pigmentary glaucoma.

Two young brothers were bilaterally affected by pigmentary glaucoma and extensive symmetrical changes of the retinal pigment epithelium (RPE). Fundus changes consisted in widespread salt-and-pepper RPE mottling and pigment clumping, sparing only the peripapillary and foveal areas. During the course of 4 years, one of the two patients suffered multiple, recurrent, exudative and hemorrhagic detachments of the RPE that involved the midperiphery and posterior pole. No exudative lesions appeared in the brother. The medical history and systemic laboratory tests were noncontributory in both patients. The ERG was normal and the EOG subnormal. Dark adaptation was delayed and showed an elevation of the scotopic threshold. These cases seem to support the hypothesis that the RPE is also involved in the pigmentary dispersion syndrome. An inherited defect could affect the pigment epithelium in both the anterior and posterior segments of the eye. The multifocal subretinal exudative pattern that occurred in one of our patients has not been previously observed in hereditary disorders of the RPE.

Red krypton and blue-green argon laser diabetic panretinal photocoagulation.

Eyes with three or four diabetic retinopathy risk factors received laser panretinal photocoagulation with random selection of either blue-green argon (42 eyes) or red krypton (40 eyes) laser to determine if one laser was superior to the other. After 6 months, visual acuity preservation or improvement was obtained in 33 (79%) argon- and 34 (84%) krypton-treated eyes. Peripheral IV-4e visual field constriction of 7% occurred with argon and 10% with krypton. Vitreous hemorrhaging after treatment occurred in 1 argon- and in 6 krypton-treated eyes. Complete disc neovascular regression was obtained in 27 (67%) of 40 argon- and 19 (56%) of 34 krypton-treated eyes, with partial regression occurring in 8 (20%) argon- and 8 (24%) krypton-treated eyes. The two treatments produced essentially equal results.

Retinal and choroidal ischemic syndrome, digestive tract and renal small vessel hyalinosis, intracerebral calcifications and phenotypic abnormalities: a new family syndrome.

A new family syndrome is described that affected three of seven siblings and another patient who had been abandoned at birth but came from the same area of France. All four patients were young women with a very peculiar phenotype, poikiloderma and greying of the hair, and idiopathic non-arteriosclerotic cerebral calcifications. Pathological studies demonstrated small-vessel hyalinosis due to basal membrane thickening, mainly in the digestive tract, kidneys and calcified areas of the brain. The clinical and biological expressions of these vascular changes varied. Peripheral retinal ischemic syndrome and chorioretinal scars were found in the ocular fundi of three patients. Malabsorption and protein-losing enteropathy was the main problem in all four, and was the cause of one patient's death. A subarachnoid hemorrhage due to a right sylvian aneurysm also occurred in two of the three sisters and was lethal for one. Nephropathy with renal failure and systemic hypertension is the major problem of the two surviving patients.

Sarcoidosis and peripheral neovascularization.

Twenty-eight patients with sarcoidosis were examined. Four of the patients had a history of uveitis. Retinal periphlebitis was noted in one case, and peripheral retinal neovascularization was found in two non-sickle cell black patients. Vitreous hemorrhage developed in one of the patients with neovascularization, prior to laser treatment and this patient eventually required vitreous surgery. The other patient was treated with prophylactic laser. Peripheral retinal neovascularization may be a noteworthy finding that will be found in larger numbers with attention to the retinal periphery in cases of sarcoidosis.

Microangiopathy with encephalopathy, hearing loss and retinal arteriolar occlusions: two new cases.

Two young women developed encephalopathy, hearing loss and retinal arteriolar occlusions. Their behaviour became immature and cognitive functions were severely impaired. One of the patients underwent brain biopsy, which showed several microinfarcts in both white and grey matter and microangiopathic changes, with thickened arteriolar segments staining intensely for laminin and fibronectin. These findings support the concept of a new type of microangiopathy involving the brain, inner ear and retina.

Monocular ischemia--the influence of carotid atherosclerosis versus primary ocular disease on prognosis.

The etiology of monocular ischemia influences the clinical manifestation and long-term neurologic and visual prognosis. During a 10-year period, 140 patients with monocular visual symptoms were evaluated and assigned to a carotid bifurcation occlusive disease group (group I) or a primary ocular disease group (group II) on the basis of angiographic findings and ophthalmologic evaluation. Patients with symptoms secondary to emboli from the carotid bifurcation tended to have a shorter duration of blindness and a lower incidence of permanent blindness initially and during follow-up. The presence of Hollenhorst plaques or retinal artery occlusion did not have any discriminatory diagnostic value since the incidence was similar in both patient groups. Since both primary eye disease and carotid bifurcation occlusive disease can be initially seen as monocular ischemia, carotid angiography and ophthalmologic consultation are necessary to select those patients who will benefit from carotid endarterectomy.

Uveítis y neovascularización papilar / Uveitis and papilar neovascularization

Se presentan dos pacientes portadores de uveítIs complicada con neovascularización papilar. El primer caso presenta signos de oclusión vascular retinal, que no se encuentran en el segundo, indicando que la inflamación intraocular es capaz de inducir neovascularización en ausencia de isquemia retinal. La evaluación clínica de estos pacientes debe incluir un examen ocular y sistémico completo, en busca de una condición patológica asociada. La angiofluoresceinografía es mandatoria, para evaluar el estado de la circulación retinal. La regresión de la neovascularización puede obtenerse con un adecuado control de la inflamación en muchos de estos casos. La fotocoagulación de la retina isquémica debe agregarse cuando sea necesario

Facioscapulohumeral dystrophy associated with sensorineural hearing loss, tortuosity of retinal arterioles, and an early onset and rapid progression of respiratory failure.

Two sibling cases of facioscapulohumeral dystrophy (FSHD) are described. One was characterized by sensorineural hearing loss, marked tortuosity of retinal arterioles, an early onset and progression of severe restrictive-type pulmonary dysfunction, and cor pulmonale. The other had a mild course of FSHD without involvement of any other organ than muscles at the time of diagnosis. Recently, a new nosological entity of FSHD, with sensorineural hearing loss and tortuosity of retinal arterioles, was advocated. Our cases, especially the first case, seem to belong to this newly recognized entity of FSHD. Moreover, it is noteworthy that our first case exhibited rapid aggravation of severe restrictive-type respiratory failure and cor pulmonale, leading to death, which was never seen in any other reported cases.

Contribuiçäo ao estudo da autorregulaçäo vascular da retina no glaucoma crônico / Retinal vascular auto-regulation in chronic glaucoma

Foram realizadas medidas pré e pós operatórias dos diâmetros de ramos arteriais e venosos da retina (nasais superior e inferior e temporais superior e inferior) de nove pacientes portadores de glaucoma crônico, que tiveram suas pressöes oculares reduzidas a níveis clinicamente satisfatórios através da trabeculectomia. Em sete pacientes, observou-se decréscimo significante do calibre de todos os vasos estudados, näo havendo diferença estrutural significante entre os ramos arteriais e os venosos pelo método estatístico utilizado. Em dois pacientes, cuja única característica que os diferenciava dos demais era a idade mais avançada, as reduçöes do calibre vascular foram mínimas. A diminuiçäo do calibre dos vasos da retina, em pacientes com glaucoma crônico, após o abaixamento da pressäo ocular provocada pela cirurgia, sugere a permanência da autorregulaçäo vascular retínica, mesmo depois de um regime de hipertensäo ocular de longa duraçäo

Further observations on cerebral or retinal ischemia in patients with right-left intracardiac shunts.

Between October 1983 and November 1986, 20 patients suspected of having a paradoxical cerebral or retinal embolism were identified. Cerebral infarction was the most common presentation. Six patients had a patent foramen ovale demonstrated by cardiac catheterization or surgery. Three patients had a newly discovered atrial septal defect, and one had an atrial septal defect that had previously been treated surgically. Results of the cardiac physical examination, chest roentgenography, and electrocardiography were unremarkable in 12 patients. Eighteen patients had a right-to-left shunt demonstrated by contrast echocardiography. Nine of these patients underwent cardiac catheterization; seven had abnormal catheterization study results: four had a patent foramen ovale and three had an atrial septal defect. Sixteen patients received medical therapy only while four underwent surgery. All patients survived the initial insult. There were no deaths or ischemic recurrences on follow-up ranging from one month to three years. We believe that contrast echocardiography can provide important diagnostic information, even in situations in which cardiac involvement is not suspected. Additional studies are needed before the optimal treatment of presumptive paradoxical cerebral embolism can be determined.

Blindness as a complication of rhinoplasty.

Blindness following elective cosmetic surgery can be a devastating complication, for the patient as well as the surgeon. A case of unilateral blindness secondary to central retinal artery occlusion following an open septorhinoplasty is presented. Possible causes of blindness following rhinoplasty and steps to prevent this complication are addressed.

Visualization of a developing vasculature.

The events involved in vasculogenesis still remain obscure. One difficulty has been the techniques employed to visualize angioblasts, i.e., vascular precursors, during the genesis of blood vessels. The retina provides a unique model for studying these events since it is not completely vascularized in some mammals at birth. Using a previously published magnesium-dependent ATPase technique to visualize the developing retinal vasculature and its precursors, and embedding this tissue in JB-4 methacrylate for serial sectioning, has permitted examination of the retinal vasculogenic processes in dual perspective. The technique has permitted observation of the stages in angioblast differentiation and the apparent importance of glycosaminoglycan-rich cell-free spaces in this process. Perhaps the most important observation is that initial vessel formation occurs by coalescence of angioblasts after differentiation in situ.

Structural characterization of neovascularization in adenovirus-12-induced retinal tumor.

In order to elucidate a relationship between newly formed micro-blood vessels in retinal tumor and blood-retina barrier, we studied light and electron microscopic and immunohistochemical findings of newly-formed micro-blood vessels in human adenovirus 12-induced retinoblastoma-like tumors in rats. In contrast to other experimentally induced tumors of the central nervous system, there was no evidence of formation of Weibel-Palade bodies and endothelial gaps in this experimental model of retinoblastoma, but factor VIII related antigen was evidently demonstrated. Increased pinocytotic vesicles suggested that the vast majority of these blood vessels did not retain the normal physiological barrier functions. The basement membrane of the micro-blood vessels was poorly developed. The morphological characteristics of the micro-blood vessels of this retinoblastoma-like tumor were compared with those of human retinoblastoma and other experimentally induced tumors of the central nervous system.