Prospective evaluation of digital non-stereo color fundus photography as a screening tool in age-related macular degeneration

Abstract

Purpose: To evaluate mydriatic, non-stereo digital color fundus photographs as a screening tool for identifying and classifying exudative age-related macular degeneration (AMD).

Design: Prospective case series.

Methods: Digital color fundus photographs were obtained from patients seen in the AMD screening clinic over a 9-month period at the Ivey Eye Institute in London, Ontario. Photographs for eligible patients were separated by eye, cataloged, blinded, and randomly labeled before interpretation by an experienced vitreoretinal surgeon. Exact agreement, sensitivity, specificity, positive predictive value, and negative predictive value of the fundus photographs in diagnosing, classifying, and managing cases of suspected exudative AMD were then calculated against gold standard clinical examination and fluorescein angiography.

Results: A total of 223 images were used from 118 eligible patients. Exact agreement between photographic evaluation and gold standard ranged from 89.2% (presence of pigment epithelial detachment (PED)) to 82.5% (evidence of retinal pigment epithelium geographic atrophy). Sensitivities ranged from 89.2% (presence of choroidal neovascular membrane (CNVM)) to 40.0% (presence of PED). Specificities ranged from 94.1% (presence of PED) to 86.8% (presence of retinal pigment epithelium geographic atrophy). Positive predictive value ranged from 86.1% (presence of CNVM) to 40.0% (presence of PED). Negative predictive value ranged from 94.1% (presence of PED) to 88.9% (presence of CNVM). As a screening tool for high-risk dry changes and active exudative changes, overall sensitivity specificity, positive predictive value, and negative predictive value were 82.1%, 79.1%, 70.4%, and 88.0%, respectively.

Conclusions: Digital, non-stereo color fundus photographs are highly sensitive and have high negative predictive value as a screening tool. Very few treatable lesions are missed using telemedicine in age-related macular degeneration.