Circularity of the foveal avascular zone and its correlation with parafoveal vessel density, in subjects with and without diabetes.

Purpose: To characterize the distribution of the foveal avascular zone circularity and its correlation with parafoveal vessel density, in subjects with and without diabetes.

Methods: Observational, descriptive, cross-sectional, and prospective study; subjects without diabetes (Group 1), with diabetes without retinopathy (Group 2), or with diabetic retinopathy (Group 3) were included. Means of foveal avascular zone circularity and parafoveal vessel density were compared between groups (Kruskal-Wallis) and their correlation was calculated with Spearman's Rho test.

Results: Seventy-seven eyes; central vessel density mean was higher in Group 1 than in Group 2 and higher in Group 2 than in Group 3; inner and complete vessel density means were also higher in Group 2 than in Group 3. The mean of the foveal avascular zone circularity did not differ between groups, and in Group 3 it had a positive correlation with central (0.45), inner (0.56), and complete (0.53) vessel densities.

Conclusions: Circularity does not differ between subjects with diabetes, with and without retinopathy, and has only a low correlation with parafoveal vessel density in people with diabetic retinopathy, which does not allow anticipating a reduction of vessel density in this disease.