Macular sensitivity and fixation patterns in patients with autosomal dominant optic atrophy

The objective of this study was to test macular sensitivity, fixation stability and fixation location using microperimetry in patients with autosomal dominant optic atrophy (ADOA) and mutation-free relatives.

This was a cross-sectional study of 43 patients with exon 28 (2826 delT) mutation in OPA1 (age 11.7-71.5 years, best-corrected visual acuity (BCVA) 20/24-20/13). The patients and 49 mutation-free first-degree relatives (BCVA 20/25-20/10) underwent ophthalmic examination including macular microperimetry out to 12° eccentricity with registration of fixation stability and fixation location.

The average (± standard deviation) sensitivity was significantly reduced in ADOA patients compared with controls, 14.9 (± 4.4) dB versus 19.7 (± 0.4) dB (p < 0.0001). In a retinotopic projection, the largest relative sensitivity deficits in ADOA were seen in the nasal macula (13.6 (± 5.7) dB versus 19.7 (± 0.7) dB) and in the central macula (14.2 (± 5.1) dB versus 19.9 (± 0.3) dB). The average sensitivity decreased with decreasing BCVA in ADOA (p < 0.0001). Stable fixation was found in 58% of ADOA patients versus 86% of controls, and relatively unstable fixation was observed in 35% of ADOA patients versus 14% of controls. Unstable fixation was found only in ADOA, where its prevalence was 7%.

ADOA was associated with unstable fixation and subnormal microperimetric sensitivity, especially in the central and nasal macula where the ganglion cell deficit is most pronounced.

The study was supported by Øjenfonden, Øjenforeningen, and Synoptikfonden.

NCT01522638.