Purpose: To evaluate the prevalence of anterior type diabetic retinopathy (DR) using ultra-widefield fluorescein angiography and to identify the factors associated with anterior type DR incidence.
Methods: A retrospective case review was used in this study. Patients with non-proliferative diabetic retinopathy (NPDR) underwent examination by ultra-widefield fluorescein angiography, and were classified into anterior, posterior, or diffuse DR groups. Anterior DR was defined if diabetic retinal changes were noted only at the location anterior to the imaginary circle bordered by the Early Treatment Diabetic Retinopathy Study seven-standard fields. Correlations between demographic data, as well as systemic and ocular factors, and the incidence of NPDR types were evaluated.
Results: Among the 234 eyes of 234 patients with NPDR, 25 eyes (10.7%) demonstrated anterior DR. Anterior DR was observed in 10 eyes (30.3%) of patients having mild NPDR, three eyes (4.8%) of moderate NPDR patients, and in 12 eyes (7.1%) of severe NPDR patients (p < 0.001). The incidence of anterior DR positively correlated with lower hemoglobin A1c levels and with greater high-density lipoprotein levels following multiple logistic regression analysis (p < 0.001). The mean hemoglobin A1c level was 7.03 ± 0.99% in anterior DR, 7.99 ± 1.74% in posterior DR, and 7.94 ± 1.39% in diffuse DR patients (p = 0.003). The mean high-density lipoprotein level was 51.2 ± 12.5 mg/dL in anterior, 49.7 ± 15.2 mg/dL in posterior, and 45.2 ± 13.1 mg/dL in diffuse DR patients (p = 0.010).
Conclusions: Diabetic retinal changes confined to an anterior location were more frequently noted in earlier stages of NPDR. The incidence of DR sparing posterior retinal involvement was related to favorable blood sugar and lipid profiles.
Keywords: Diabetic retinopathy; Fluorescein angiography.