Purchase this article with an account.
L. Tarita-Nistor, E. G. Gonzalez, M. H. Brent, M. J. Steinbach; Fixation Stability and Binocular Viewing in Patients With AMD and Large Interocular Acuity Differences. Invest. Ophthalmol. Vis. Sci. 2010;51(13):2536.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Monocular fixation stability of patients with age-related macular degeneration (AMD) is impaired and worsens with increased eccentricity. Many of these patients have one eye more affected than the other. We examined fixation stability of patients with large interocular acuity differences, and its influence on their binocular visual performance.
Monocular and binocular acuities of 10 patients with AMD were measured with the ETDRS. Fixation stability of the better and worse-seeing eye was recorded in three viewing conditions: 1) Monocular viewing (MP-1 microperimeter). 2) Monocular viewing with binocular recording (EyeLink eyetracker): better-seeing eye viewing while worse eye was covered by a filter, but its fixation recorded. 3) Binocular viewing with binocular recording (EyeLink eyetracker). Fixation stability was quantified by calculating bivariate contour ellipse area (BCEA).
For the better-seeing eye, acuity correlated with BCEA in the three viewing conditions (Spearman’s r(8) = .56, .67, and .72, p < .05). For the worse-seeing eye, acuity did not correlate with BCEA in any condition. Binocular acuity correlated with the BCEA of the better-seeing eye in all conditions (Spearman’s r(8) = .62, .69, and .64, p < .05), but with the BCEA of the worse-seeing eye only in the binocular condition (Spearman’s r(8) =.63, p < .05).Fixation stability of the better-seeing eye remained constant in all three viewing conditions. BCEA of the worse-seeing eye was more than double that of the better-seeing eye in the two monocular conditions (155%, and 108% respectively), but only 31% larger in the binocular condition.
Fixational ocular motor control and visual acuity are driven by the better-seeing eye when patients with AMD and large interocular acuity differences perform the tasks binocularly.
This PDF is available to Subscribers Only