Factors influencing sensory outcome following surgical correction of infantile esotropia.

INTRODUCTION: The aims of this study are to compare the binocular function following 7mm vs. standard (3.5 to 6.5mm) bilateral medial rectus recessions, and to determine whether timing of surgery or duration of misalignment prior to surgery impact on binocular function. Methods : Participants were 85 children with infantile esotropia: all had deviations of 50(Δ) or more and were followed for a minimum of four years. At a mean age of 7 years binocular function was assessed with the Randot(©)©Preschool stereo test, the Titmus(©) fly, and the Worth 4 dot test. Results : There were 37 children in the 7mm recession group and 48 in the standard recession group. There was no difference in binocular sensory outcome for either stereopsis (P = 0.3) or fusion between the two types of surgery. For all children the duration of misalignment prior to initial surgery (P < 0.01) and age at alignment (P = 0.04) were associated with stereopsis. Duration of alignment following first surgery, however, was not associated with stereopsis (P = 0.5). DISCUSSION: In this study 7mm bilateral medial rectus recessions did not result in improved binocular sensory outcome compared to standard recessions. The most important factor associated with good binocular sensory outcome was a short duration of misalignment prior to surgery.