Non-Mydriatic Panoramic Fundus Imaging Using a Non-Contact Scanning Laser-Based System

Abstract

A non-contact scanning laser-based retinal imaging system produces a 200 degrees wide-field panoramic image of the fundus through the novel use of a large elliptical mirror. The authors investigated whether accurate diagnoses could be made from these images alone. Images were obtained from both eyes of arbitrarily selected patients and were retrospectively reviewed by retinal specialists. Each physician made a diagnosis, suggested the follow-up interval, and determined whether any intervention was needed based solely on image review. Diabetic retinopathy was categorized as background retinopathy only, preproliferative retinopathy, maculopathy, and proliferative retinopathy. The results of the image review were then compared with the results of clinical examination, and the sensitivity and specificity of the review were calculated. The correct overall diagnosis was made by the two specialists in 87% and 77% of cases, respectively; the specificity and sensitivity each averaged 76%. Follow-up interval recommendations from image review matched those made on clinical examination in 86% of cases. Diabetic retinopathy was correctly identified as a general diagnosis with a sensitivity of 94% and the follow-up recommendations corresponded to the clinical recommendations in 82%. Sixty-two percent of the images were judged to be of good quality or better, with only 6.4% deemed unreadable. Iris color did not influence image quality. The non-contact scanning laser-based retinal imaging system provides images of sufficient resolution and clarity to make accurate general diagnoses in a high percentage of cases. Its use as a screening device for specific diseases is feasible and merits further study.