Abstract
Purpose:
To test macular sensitivity, fixation stability and fixation location using microperimetry in patients with autosomal dominant optic atrophy (ADOA) and their mutation-free first degree relatives.
Methods:
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) 20/724 - 20/13) and 49 mutation-free family members (BCVA 20/25 - 20/10) underwent ophthalmic examination including macular 12° eccentricity microperimetry. Stable fixation was defined as 75% or more fixation points being within 2° from the center of the fovea, predominantly central fixation as 50% of fixation points within 2°, while poorer fixation was labelled relatively unstable and predominantly eccentric fixation.
Results:
Average sensitivity was significantly reduced in ADOA patients compared to controls, 14.9±4.4 dB versus 19.7±0.42 dB (p<0.0001). In a retinotopic projection, the largest relative sensitivity deficits in ADOA were seen in the nasal (13.0±6.8 dB versus 19.9±0.38 dB), inferonasal (12.8±6.4 dB versus 19.8±0.43 dB) and central (13.2±5.5 dB versus 19.8±0.43 dB) fields of the macula. Average sensitivity decreased with decreasing BCVA in ADOA (r=0.74, p<0.0001). Stable fixation was found in 58% (25/43) of ADOA patients and 86% (42/49) of controls, relatively unstable fixation in 35% (15/43) of ADOA patients and 14% (7/49) of controls, whereas unstable fixation was found only in ADOA, where the prevalence was 7% (3/43).
Conclusions:
ADOA was associated with unstable fixation and subnormal microperimetric sensitivity, especially in the central and nasal half of the macula where the ganglion cell layer thickness is the lowest in ADOA.
Keywords: 613 neuro-ophthalmology: optic nerve •
758 visual fields