Evaluating the Reliability of a Microperimetry-Based Method for Assessing Visual Function in the Junctional Zone of Geographic Atrophy Lesions.

PURPOSE

To assess the repeatability of a microperimetry methodology for quantifying visual function changes in the junctional zone of eyes with geographic atrophy (GA) in the clinical trial context.

METHODS

A post hoc analysis of the OAKS phase III trial was conducted, which enrolled patients with GA secondary to age-related macular degeneration. Microperimetry using a standard 10-2 fovea centered grid was performed at baseline and follow-up visits. GA regions were traced on fundus autofluorescence (FAF) images. Two graders independently registered baseline microperimetry images with baseline FAF images in a sampling of 30 eyes from the OAKS study. Agreement between the two graders' assessments of mean sensitivity and the number of scotomatous points within a ±250 m GA junctional zone was assessed.

RESULTS

The intraclass correlation (ICC) and coefficient of repeatability (CoR) for the mean junctional zone sensitivity were 0.994 and 0.349 dB, respectively. The ICC and CoR for the total number of scotomatous points within the junctional zone were 0.997 and 0.218, respectively.

CONCLUSIONS

The repeatability of the methodology and its compatibility with standard MP acquisitions appear to make it well-suited for identifying and analyzing retinal sensitivity within high-risk areas of the retina.