Abstract
Abstract
Epiretinal Membranes in PVR and Subretinal Membranes in AMD - Are They Anything More than Hyper-Regeneration at a Wrong Place?
Vidinova C., Vidinov K. Medical University, Vitreoretinal Clinic, Department of Ophthalmology, Sofia, Bulgaria
Purpose: To compare the ultrastructural characteristics of the epiretinal membranes in PVR patients with those in the subretinal membranes of people with AMD. To follow the changes in the cells and the extracellular matrix in the two types of membranes. Method: We used epiretinal membranes taken during vitrectomy of 34 patients with PVR and subretinal membranes taken also during intravitreal surgery of 11 patients with ARMD associated with massive subretinal haemorrhage. The materials were used for transmission and scanning electron microscopy and for histochemical investigation with Safranin O. Results: RPE and Fibroblast like cells were preliminary observed in the epiretinal membranes of the PVR patients. The cells were usually connected to each other with tight intercellular junctions- (zonule occludens). Some of the RPE cells showed altered characteristics limited number of pigment granules, changed shape, clustering of mitochondrial complexes around the cell nucleus. In the extracellular matrix collagen fibres type I collagen and a great number of proteoglycan complexes were observed. The subretinal membranes in ARMD patients consisted mainly of fibroblasts and isolated or grouped RPE cells. Numerous capillaries of subretinal blood vessels were also found. The RPE cells showed marks of degeneration: picnotic nuclei, distorte
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