Retinal revascularization following laser photocoagulation treatment for choroidal neovascular membranes

P. J. Caskey and J. C. Folk
Department of Ophthalmology, University of Iowa Hospitals and Clinics, Iowa City.

Retinal revascularization developed within the treatment scar in 7% of patients who had laser photocoagulation treatment for a choroidal neovascular membrane. This revascularization could be mistaken for recurrent choroidal neovascularization because it initially proliferated into a glomerularlike structure and showed dye leakage on angiography. Unlike choroidal neovascularization, these vessels, however, filled entirely from the retinal circulation and stereoscopic angiograms showed them to be located in the inner retina. In the 20 patients who were followed up, the retinal revascularization first appeared approximately four weeks after treatment and persisted for an average of ten weeks. It was associated with dense laser scarring, retinal capillary obliteration, and internal limiting membrane wrinkling, suggesting that heavy initial laser treatment was a predisposing factor for its development. It is important to differentiate retinal revascularization, which has an excellent prognosis and does not require re-treatment, from recurrent choroidal neovascularization, which usually must be treated promptly to avoid loss in visual acuity.