[Morphological study on the intraocular proliferative membrane of proliferative diabetic retinopathy and...

The membranes from 42 eyes with PDR and 8 eyes with PVR were removed during vitreous surgery. In 12 of those with PDR and 3 of the cases with PVR, the reproliferated membranes formed beneath silicone oil (SO) were removed and were histologically and immunohistochemically examined, using morphometrical quantitative analysis. In each case, area coefficient, fibrous content and the number of new vessels, and thick basement membranes, increased wall cells and multilayer basement membranes of new vessels were studied. In both PDR and PVR, the number of cells per unit area tended to be increased with the period of time after SO was injected, while the percentage of fibrous components did not change. The Percentage of occurrence of each type of new vessels was almost the same in both primary and reproliferative PDR membranes. In the primary proliferative PDR membranes, endothelial cell proliferation was found predominantly, while glial hyperplasia was predominant in the primary proliferated PVR membranes and the reproliferated membranes under SO of PDR and PVR.