Abstract
Purpose :
Using OCT, we were able to measure eccentric fixation in children with residual amblyopia (Jin et al, 2020). We found that the OCT fixation shift is significantly higher in amblyopic eyes than in fellow eyes, especially in strabismic amblyopia. However, we do not know whether eccentric fixation is stable over time. Here we report long-term follow-up of the OCT fixation shift in children with amblyopia.
Methods :
Children with amblyopia (N=24) and normal controls (N=9) were studied. At their first visit (baseline), they ranged from 4 to 16 (8.5±3.1) years old; amblyopia was classified into anisometropic amblyopia subgroup (N=9) and strabismic amblyopia subgroup (N=15). All had baseline and follow-up visits and the follow-up duration from baseline was 2.7±1.8 years (5 months to 6 years). Spectral-domain OCT was used to estimate fixation shift. We asked the participant to focus on the internal dot target of the OCT. OCT fixation shift, i.e. the distance between the fovea and the fixation point, was measured, adjusted for axial length, and converted into visual degrees. Fixation shifts in the amblyopic eye, the fellow eye, and the right eye of the Control Group were compared by ANOVA. Baseline and follow-up results in the strabismic group were compared with the paired t-test. We also compared fixation shift change with visual acuity change between two visits for anisometropic versus strabismic amblyopia.
Results :
At the baseline visit, the mean fixation shift was 0.05±0.10° for control eyes, 1.50±1.87° for amblyopic eyes, and 0.28 ± 0.51° for fellow eyes. At the follow-up visit, changes of fixation shift from baseline were -0.02±0.06° (CI 95%:-0.10, 0) for control eyes, 0.37±1.48° (CI 95%: -0.62, 2.68) for amblyopic eyes, and 0.10 ± 0.42° (CI 95%: -0.25, 0.90) for fellow non-amblyopic eyes.(F=0.62, P=0.54). Furthermore, in the strabismic subgroup, the difference between baseline and follow-up fixation shift was 0.64±1.21° (CI 95%: -0.62, 3.92), which did not change significantly (T=1.37, P=0.19). The visual acuity change and the fixation shift change were not significantly correlated (R=0.24, P=0.39).
Conclusions :
Eccentric fixation, assessed by OCT fixation shift, is relatively stable during long-term follow-up of children with unilateral amblyopia.
This is a 2021 ARVO Annual Meeting abstract.