Microperimetry in Foveal Sparing Atrophic Late-Onset Retinal Degeneration

PURPOSE: To understand the baseline and longitudinal microperimetry (MP) characteristics in foveal sparing atrophic Late-Onset Retinal Degeneration (L-ORD).

METHOD: Prospective, cross-sectional, longitudinal study in which patients from the retina clinics of two academic teaching hospitals were included. Mesopic microperimetry was performed using a Nidek MP-1 micro-perimeter. Mean total, foveal, inner ring, and outer ring sensitivities were analyzed.

RESULTS: A total of 20 eyes from 10 patients had baseline data. The subset of 10 eyes from 5 patients had follow-up data. The mean baseline macular sensitivity was 10.02 dB (+/- 5.26) with findings showing symmetry between both eyes. In the follow-up cohort, there was a significant loss of outer ring (0.83 dB per year, p= 0.0001), inner ring (0.67 dB per year, p=0.034), and foveal sensitivity (0.92dB loss per year, p= 0.015), while the mean sensitivity decreased significantly (0.66 dB per year, p = 0.0008) at 4-year follow-up. The drop in mean sensitivity was associated with significant increases in the number of deep scotoma points (6.20, p=0.037) and a decrease in the number of normal points (-6.30, p=0.022).

CONCLUSION: Microperimetry is a useful tool for macular function follow-up to measure disease progression in L-ORD.