Enhancing surgery for acquired esotropia.

In acquired esotropia, operating only on the non-accommodative angle often results in undercorrection. To decrease the frequency of this outcome, we enhanced surgery in a preliminary study by operating for a target angle equal to half the sum of the distant non-accommodative angle (minimum 12 prism diopters) plus the distant angle measured without correction. The mean augmentation in 12 patients undergoing bimedial rectus recession was 0.8 +/- 0.2 mm, and in eight patients who had a previous bimedial rectus recession and were undergoing a bilateral rectus resection it was 1.7 +/- 0.8 mm. With a mean follow-up of 26 +/- 20 months, 13 patients were within 10 prism diopters of orthotropia and four were undercorrected. Three overcorrected patients were orthophoric after reducing the hyperopic correction. All 17 patients old enough to cooperate had stereopsis or a positive Worth four-dot test at some point postoperatively.