Histopathology of focally photocoagulated preretinal new vessels

The histopathologic effects of focal xenon arc and argon laser photocoagulation on three patches of preretinal new vessels were studied in a patient with proliferative diabetic retinopathy. Both treatment modalities achieved total obliteration of the vessels. However, the adjacent retina and choroid were severely damaged, and preretinal membranes were seen over all three patches. Local tissue destruction is minimized when preretinal neovascularization is treated indirectly by scatter photocoagulation. Currently, scatter photocoagulation is our treatment of choice.