Screening for diabetic retinopathy using digital colour photography and oral fluorescein angiography

Purpose: To evaluate digital colour photography and oral fluorescein angiography (OFA) for diabetic retinopathy screening. 
Methods: Thirty-seven patients were selected from either a diabetic retinopathy screening or a medical retina clinic. Three 45° colour digital images and a single macula 45° OFA image were taken from each eye. Standard seven- field stereo photography with ETDRS grading was used as a gold standard for data comparison. The images were assessed by two graders and the results of each method compared using the McNemar test. 
Results: Five eyes had no diabetic retinopathy, 50 had background diabetic retinopathy, 3 had pre-proliferative diabetic retinopathy, 11 had proliferative disease and 3 had quiescent post- treatment disease. Clinically significant macular oedema was present in 25 eyes and absent in 48. For grading diabetic retinopathy digital colour photography produced a sensitivity of 0.87 (specificity 0.83); OFA produced a sensitivity of 0.87 (specificity 0.80) (p = 0.1). For the detection of diabetic maculopathy, the sensitivity of digital colour photography was 0.48 (specificity of 0.95) and for OFA was 0.87 (specificity 0.87) (p < 0.01). 
Conclusion: This pilot study has shown that both digital colour photography and OFA compare well with conventional methods for diabetic retinopathy screening. The results encourage the further evaluation of OFA in the screening for diabetic maculopathy.