Comparison of Improvement Rates between Distance and Near Visual Acuity in Children with Unilateral Amblyopia

Abstract

Purpose: To compare the improvement rates of distance visual acuity (VA) with that of near VA in amblyopic eyes of children with unilateral amblyopia.

Methods: The medical records of children with unilateral amblyopia successfully treated with patching were reviewed. During subsequent visits for amblyopia treatment, subjects had best-corrected VA measured at 4 meters and 1/3 meters every 2 months. Duration of treatment to achieve equal VA between both eyes and improvement rates were compared between distance and near, and analyzed according to the cause and severity of amblyopia, or age.

Results: A total of 76 children with amblyopia due to anisometropia and/or strabismus started amblyopia treatment at a mean age of 5.8 years and were followed up during a mean period of 16.4 months. Baseline VA was better at near than at distance in 52 children (68.4%), and better at distance than at near in 4 (5.3%). The mean duration of treatment was 5.4 months at distance and 3.9 months at near. However, the improvement rate considering the amount of improvement of VA was faster at distance; 0.11 log MAR/month at distance, and 0.08 log MAR/month at near (p = 0.016). The improvement rate differences between distance and near did not differ based on the cause of amblyopia, or age, whereas in mild amblyopia the improvement rate of distance VA was significantly faster than near. Additionally, children with better initial near VA tended to have a faster improvement rate of distance VA.

Conclusions: Although baseline VA was better at near than at distance in more patients, the improvement rate was faster at distance than at near. Children with better initial near VA appeared to have a faster improvement rate of distance VA.