Using a special embedding method, autopsied eyes with proliferative diabetic retinopathy were studied. In areas with no posterior vitreous detachment, small proliferations may arise multifocally and grow within the vitreous cortex. The fibrous material of the vitreous cortex is densely interconnected with and obviously incorporated into the newly formed proliferated tissue, a process which causes coarse traction lines on the vitreous cortex lamellae. The clinical consequences of these findings are discussed.