Purpose: To describe the transition to digital imaging and assess any impact on ocular disease classification.
Methods: Film and digital images, acquired by certified photographers, were evaluated independently according to standard procedures for the following: image quality, presence of cytomegalovirus retinitis lesions, and their extent and proximity from disk and macula. Intergrader agreement within the digital medium was also assessed.
Results: Among the 15 eyes with cytomegalovirus retinitis, the mean difference between film and digital images for linear distance of lesion edge to disk was 0.02 disk diameters, for distance to center of macula was -0.04 disk diameters, and area covered by cytomegalovirus retinitis was 0.95 disk area. There was no statistically significant difference in distance and area measurements between media. Intergrader agreement in measurements of digital images was excellent for distance and area estimated.
Conclusion: Our results suggest that digital grading of cytomegalovirus retinitis in Longitudinal Studies of the Ocular Complications of AIDS is comparable with that from film regarding disease classification, measurements, and reproducibility. These findings provide support for continuity of grading data, despite the necessary transition in imaging media.