Manual Versus Semi-Automated Measurement of Geographic Atrophy Area in Eyes With Age-Related Macular Degeneration.

Abstract

PurposeTo investigate the agreement between and correlation of manual and semi-automated area measurements of geographic atrophy (GA) in eyes with age-related macular degeneration (AMD) using Heidelberg Eye Explorer and ImageJ software.MethodsFundus autofluorescence (FAF) images of eyes with GA secondary to AMD were analyzed. Two graders measured the atrophic area using Heidelberg Eye Explorer manual and semi-automated (RegionFinder) software, as well as ImageJ manual and semi-automated (Color Threshold) software.ResultsFifty-four FAF images were analyzed. The mean (SD) areas were 10.55 (11.4) mm2 and 9.6 (9.8) mm2 using the Heidelberg manual and semi-automated tools, respectively. The mean (SD) areas were 11.04 (12.25) mm2 and 9.75 (10.3) mm2 using ImageJ manual and semi-automated tools, respectively. Compared with the semi-automated Heidelberg RegionFinder (gold standard) area measurements, Bland–Altman plots showed mean differences of 0.96 mm2, 1.4 mm2, and 0.16 mm2 with manual Heidelberg, manual ImageJ, and semi-automated ImageJ measurements, respectively. Homogeneous GA lesions showed less disparity in area measurements across modalities compared with non-homogeneous lesions.ConclusionsImageJ appears to be a reliable tool for GA area measurements when proprietary OCT software is unavailable. Manual measurements with Heidelberg Eye Explorer and ImageJ were comparable, as were semi-automated measurements with Heidelberg RegionFinder and ImageJ Color Threshold.Translational RelevanceNovel GA measurement techniques using open-source software appear to be comparable to established techniques using proprietary platform-specific software, which may permit more widespread analysis of GA progression from multiple platforms and databases.