Diabetic retinopathy screening using single-field digital fundus photography at a district level in Costa Rica: a pilot study.

To report on our initial experience screening for diabetic retinopathy (DR) using digital fundus photography and standarized criteria. Cross-sectional prospective study of all 1327 diabetic patients referred to the Ophthalmology Department of the Clorito Picado Clinic in San José, Costa Rica between April 2008 and March 2009. Patients were screened with a single-field 45-degree digital color retinal image centered on the fovea. The main outcome measures were prevalence of DR, waiting time for a fundus photograph appointment and the number of patients that needed to be evaluated by an ophthalmologist. In this population of 1327 patients, 85% did not have any retinopathy. The prevalence of DR was 15%. Mild non-proliferative DR (NPDR) was seen in 5.8% (70/1215), moderate NPDR in 3.9% (47/1215), severe NPDR in 4.7% (57/1215) and proliferative DR in 0.6% (8/1215). Macular edema was present in 2.6% (32) patients. 13.8% of patients required pupillary dilation for an adequate image to be taken and 8.8% of the images were unreadable. The average waiting time for a fundus photograph appointment was 49.1 days. A total of 13.8% (183/1327) patients were referred to the ophthalmologist. Of these referrals, 61.2% (112/183) were because of unreadable images and 38.8% (71/183) were referred for further ophthalmic treatment. Digital fundus photographic screening for DR appears to be a viable option for the improvement of screening for DR in Costa Rica.