Development of a multi-field fundus photographing system using a non-mydriatic camera for diabetic retinopathy

A new fundus photographing system was developed for diabetic subjects with or without simple diabetic retinopathy using a non-mydriatic fundus camera. Eight internal fixation targets were incorporated in a non-mydriatic fundu s camera (TRC-NW5S; TOPCON, Tokyo, Japan), interfaced with a 3CCD color cam era. Nine 45 degrees fundus photographs were taken in 22 healthy volunteers and 16 diabetic subjects, and stored as digital images. Fundus images were reconstituted as collages on the monitor and printed out. The combined ang le reached 94 degrees in collage, and the average times required for photog raphing with and without mydriasis were 3 min 26 s and 4 min 36 s, respecti vely. The concordance of fundus images between the first and second photogr aphs of healthy volunteers with and without mydriasis was 95.4% (n = 22). T he quality of the photographs, graded on a five-point scale (5, full) by th ree doctors, was 4.3 +/- 0.6 in the volunteers without mydriasis, 4.7 +/- 0 .4 in the diabetics without mydriasis, and 4.8 +/- 0.3 in the volunteers wi th mydriasis. In retinas with diabetic retinopathy, the system was able to depict microaneurysms, hemorrhages, hard exudates and soft exudates. This n ew system was satisfactory for the screening and follow-up of diabetic reti nopathy. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.