Retinal vascular pattern in familial exudative vitreoretinopathy.

We evaluated the retinal vascular pattern in 133 eyes (77 cases) with familial exudative vitreoretinopathy (FEVR). A wide variety of retinal vascular abnormalities were observed in the extreme fundus periphery, particularly in the temporal retinal sector. They included: presence of an avascular zone in the extreme periphery, vasodilation and arteriovenous anastomosis in the peripheral vascularized retina, v-shaped avascular zone along the temporal meridian, and neovascularization. A grading system into five types was proposed with these features as parameters. Macular ectopia, falciform retinal fold and vitreoretinal adhesion appeared to be secondary to retinal vascular abnormalities. The presence of sporadic FEVR is postulated.