Objective To investigate the pathological spectrum of hypertensive retinopathy. Methods Systemic hypertension was produced experimentally in SD rats by partially constricting the right renal artery and removing the left kidney.The eyes obtained from hypertensive animals at 2 weeks,1,2,4months were examined by means of light microscopy,immunohistochemical staining,electron microscopy and histochemical electron microscopy and compared with the control group. Results 1.From 2 months after surgery,thickening of retinal capillary basement membrane(RBM)became apparent.2.From then on,RBM showed an increased staining reaction for type Ⅳcollagen and laminin,while staining reaction of RBM for fibronectin in hypertensive rats was negative at any stages.The number of anionic sites within the RBM was gradually reduced following the development of hypertension and it was definitely decreased at 4 months. 3.A few deteriorated endothelial cells were lifted focally from the RBM with subendothelial swelling in retinal vessels at 2 weeks,and the pericytes exhibited edema and deterioration at 4 months. Conclusions Detachment of the endothelial cells from the RBM,thickening of the RBM companied with the reduction of anionic sites and deterioration of pericytes may be responsible for hypertensive retinopathy. (Chin J Ocul Fundus Dis, 1999, 15: 163-166)
At present, intravitreal injections of anti-VEGF agents is the main method for the treatment of macular edema secondary to retinal vein occlusion (RVO), which can significantly inhibit neovascularization, release macular edema and improve the vision of patients. However, VEGF is a survival factor of vascular endothelial cells, whether it can lead to the progress of retinal ischemia and it has an effect on retinal capillaries deserves our clinical attention. Most scholars currently think that the anti-VEGF agents will not aggravate the occlusion of retinal capillaries in the treatment of macular edema secondary to RVO from the aspects of the changes of perifoveal capillary arcade, the quantification of foveal avascular zone area, retinal nonperfusion area and retinal vascular density of the superficial and deep capillary plexus In addition, the changes of these indicators may be related to the number of times patients need treatment, visual prognosis and so on. In the future, with the gradual popularization of OCT angiography and the prolongation of the number and time of anti VEGF drug treatment, we look forward to the study of larger samples and longer follow-up time to further analyze the influence of the retinal capillary after anti-VEGF therapy in patients with macular edema associated with RVO.