Assessment of diabetic retinopathy using two-field 60° fundus photography. A comparison between red-free, black-and-white prints and colour transparencies

Abstract

To assess the severity of diabetic retinopathy and maculopathy by comparing two different photographic methods; two-field 60 degrees photography using red-free, black-and-white prints and colour transparencies. Two ophthalmologists independently graded the photographs of 74 patients using grading scales for retinopathy and maculopathy designed for 60 degrees photography. A set of nine 60 degrees red-free, black-and-white standard photographs were chosen to represent the severity of principal diabetic retinopathy and maculopathy abnormalities. The inter-observer agreement for five pooled retinopathy severity levels was 88% (kappa 0.83, weighted kappa 0.96) and 81% (kappa 0.73, weighted kappa 0.89) using red-free, black-and-white prints and colour transparencies respectively. The corresponding figures for six pooled maculopathy levels were 96% (kappa 0.84, weighted kappa 0.97) and 93% (kappa 0.67, weighted kappa 0.86). The analyses revealed that red-free, black-and-white prints disclosed a higher severity level of retinopathy in 83% (Grader 1) and 76% (Grader 2) in those eyes for which the grading was discordant. High-quality monochrome, red-free, wide-angle fundus photographs may be useful for the detection of early and advanced diabetic retinopathy.