Targeted High-Density Microperimetry Testing of Nascent Geographic Atrophy in Age-Related Macular Degeneration.

Purpose: To examine the effectiveness of a targeted high-density microperimetry testing strategy for detecting visual sensitivity abnormalities in eyes with nascent geographic atrophy (nGA) when compared with standard central microperimetry testing.

Design: Observational study.

Participants: Three-hundred and twenty-one eyes from 176 individuals with nonneovascular age-related macular degeneration (AMD).

Methods: Thirty-five eyes from 33 participants underwent targeted high-density microperimetry testing of atrophic lesions (either nGA or geographic atrophy [GA]) within a 1.75° radius (or approximately 1000 μm diameter) region. Another cohort of 286 eyes from 143 participants with bilateral large drusen at baseline underwent standard microperimetry testing of the central 6 radius region at 6-monthly intervals for up to 36 months and thus included eyes that developed nGA and GA over the follow-up. All eyes underwent 2 tests at each visit to evaluate intrasession measurement repeatability.

Main Outcome Measures: Magnitude of visual sensitivity abnormalities based on mean sensitivity (MS), pointwise sensitivity standard deviation (PSD), and the number of test locations with a threshold of ≤ 10 decibels (dB; or deep defects) in eyes with nGA, compared between eyes that underwent targeted high-density microperimetry testing and standard central microperimetry testing.

Results: The magnitude of visual sensitivity abnormalities based on MS, PSD and the number of deep defects were all significantly greater in eyes with nGA using targeted, high-density microperimetry testing compared with eyes with nGA using standard central microperimetry testing (all < 0.001) and were all significantly less than eyes with GA using targeted, high-density microperimetry testing (all ≤ 0.004). The intrasession coefficient of repeatability, where 95% of the test-retest differences are expected to occur, for MS in eyes with atrophic changes was 0.9 dB with the targeted, high-density microperimetry testing, and 1.8 dB with standard central microperimetry testing.

Conclusions: Targeted, high-density microperimetry testing enabled the detection of a significantly greater magnitude of visual sensitivity abnormalities in eyes with nGA than standard microperimetry testing.

Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.