[The role of lipid metabolism and antioxidant system changes in the development of retinal vein occlusion].

PURPOSE: To compare changes in lipid metabolism and antioxidant status in patients with retinal vein occlusion (RVO) with that in patients with a history of ischemic stroke and in patients with no clinical manifestations of atherosclerosis. MATERIAL AND METHODS: A total of 111 patients were enrolled in the study. Group 1 included 80 patients with RVO and grade 2-3 stage II-III essential hypertension, group 2-11 patients with grade 3 stage III essential hypertension, high cardiovascular risk and a history of ischemic stroke. The control group included 20 patients with no clinical manifestations of atherosclerosis. All patients underwent a standard ophthalmic examination, fluorescent retinal angiography, lipid metabolism and redox system assessment. RESULTS: The levels of low-density lipoproteins (LDL) and cholinesterase were higher in study groups than in controls regardless the type of RVO. A statistically proven increase in oxidized LDL (oxLDL) was found in patients with complicated hypertension and ischemic RVO. A direct correlation was determined between the level of anti-oxLDL IgG and lipid peroxidation activity (LP) (R = 0.376; p = 0.136) as well as the levels of glutathione peroxidase (GPx) (R = 0.529; p = 0.029) and GPx per gram of hemoglobin (R = 0.543; p = 0.024) in patients with branch RVO. Redox system assessment showed a decrease of thiols and an increase of LP metabolites. CONCLUSION: The results demonstrated that retinal vein occlusions develop under disorders of lipid metabolism similar to those in patients with a history of ischemic stroke. The correlation between the level of anti-oxLDL IgG and LP points to the redox system involvement in the intricate pathogenesis of RVO.

[Morphological manifestations of systemic atherosclerosis found in fundus (experimental study)].

Results of angiography and morphology of 32 eyes (16 chinchilla rabbits) with experimental atherosclerosis are presented. N.N. Anichkov and S.S. Khalatova experimental hypercholesterolemia model (1912) was used. The animals were divided into the following groups: initial and advanced atherosclerosis, control group, follow-up 3 and 6 months. After 3 months progressive reduction of perfused retinal vessels and early degenerative changes of neurons and photoreceptors were found. In 6 months these changes became more significant and generalized. Due to ongoing small vessel reduction blood flow went to the major vessels and changed its distribution followed by ischemia of adjacent retina. No changes in choriocapillary layer and retinal pigment epithelium were found in any of groups studied.

[Ocular changes in systemic atherosclerosis].

Up-to-date aspects of ocular changes in systemic atherosclerosis are reviewed. At the present time despite of wide use of current methods of ocular blood circulation and retina examination there are no papers that allow to estimate dynamics of impairment of visual functions from different viewpoints (clinical, functional, blood flow, morphological etc.) in initial isolated ocular atherosclerosis. Etiology, pathogenesis and ideas about potential effect of systemic atherosclerosis on the eye are discussed. Features of blood flow in optic nerve head compared to retinal vessels are described. According to the last data correlation between the degree of reduction of a-wave of scotopic electroretinogram and deterioration of haemodynamic parameters exists.