Hemoglobin SC disease and iris atrophy

Atrophic iris lesions as well as the typical retinal lesions were found in the eyes of two patients with sickle cell hemoglobin C disease. In the first patient, atrophic areas were present in both irides. The second patient was monocular, but iris atrophy was observed in the enucleated specimen as well as in the intact eye. Iris angiography showed leakage from stromal neovascularization. In one iris, a vascular formation suggesting a sea-fan configuration was seen. Although one patient was diabetic, no ophthalmoscopic or angioraphic evidence of diabetic retinopathy was found. The atrophic lesions appear to represent ischemic necrosis secondary to sickling at the level of the iris vessels. Neovascularization may occur secondarily as a response to iris ischemia, and may thus be analogous to the neovascularization that characterizes proliferative sickle retinopathy.