Foveal avascular zone diameter and sickle cell disease.

Patients with sickle cell disease can have a distinct retinopathy in which the posterior pole shows abnormalities, including perifoveolar vascular abnormalities. The foveal avascular zone (FAZ) was examined using fluorescein angiography in patients with sickle cell disease and in healthy normal controls. The longest FAZ diameters of 38 patients (51 eyes) with sickle cell disease were compared with those of the 48 patients (60 eyes) in the control group. The average of the longest FAZ diameter in the patients with sickle cell disease was 1.00 mm compared with 0.61 mm for the controls. This difference was statistically significant (P less than .00001). Within the sickle cell group, there were no significant differences in the FAZ diameters with respect to degree of retinopathy, type of sickle hemoglobinopathy, or visual acuity. Thus, an enlarged FAZ diameter in patients with sickle cell disease is confirmed.