The effect of amblyopia therapy on ocular vestibular evoked myogenic potentials.

Clinical relevance: The development of vestibular-ocular reflex (VOR) is dependent on the visual input from both eyes. The ocular vestibular evoked myogenic potential (oVEMP) test provides an objective assessment of contralateral utricular function and associated VOR pathways.

Background: This study investigated the effects of amblyopia therapy on oVEMP responses in children with unilateral amblyopia.

Methods: Thirty patients with unilateral amblyopia (14 males and 16 females) with a mean age of 9.17 ± 2.02 years (range: 5-15 years) were examined. All participants received optimal optical correction and daily occlusion therapy (2 to 4 hours/day) for 6 months. Unilateral and bilateral stimulation of the oVEMP test was performed at baseline and 6 months after amblyopia therapy. A subgroup analysis, compared the effect of amblyopia therapy on oVEMP responses among participants with anisometropic, strabismic, and mixed amblyopia.

Results: Following six months of therapy, best-corrected visual acuity improved significantly in amblyopic eyes (p < 0.001). Significant reductions in N1 and P1 latencies were observed in the amblyopic, non-amblyopic, and bilateral stimulation conditions at six months (all, p < 0.05). However, no significant changes were found in N1-P1 complex amplitude across conditions (all, p > 0.05). A linear mixed-effects model showed that neither amblyopia type nor age significantly predicted changes in oVEMP responses following treatment (all, p > 0.05).

Conclusion: Over the 6-month follow-up, oVEMP latencies improved in both amblyopic and non-amblyopic eyes.These findings suggest a potential association between amblyopia treatment and enhanced vestibular-ocular timing. However, future controlled studies are necessary to confirm these observations and determine their clinical significance.