PRISM ADAPTATION FOR ESOTROPIA WITH A DISTANCE-NEAR DISPARITY

A series of 64 patients who had surgery for esotropia with a distance-near disparity of at least 10 prism diopters was reviewed. Thirty-three patients were prism adapted for their distance deviation (PA distance). Thirty-one patients were prism adapted for near deviation (PA near). Both groups were divided into responders and nonresponders. In the PA distance group, 22 (67%) patients were responders. All responders had surgery for their prism-adapted angle. Postoperatively, 19 (86%) responders had fusion. Thirteen (68%) required bifocals to maintain fusion. In the PA near group, 21 (68%) patients were responders. All responders had surgery for their prism-adapted angle. Ninety-four percent of responders had fusion postoperatively. None needed bifocals for fusion postoperatively and none were overcorrected. The results show that those patients who were prism adapted for their near angle, responded with fusion, and had surgery for their full amount of esotropia at prism response obtained better postoperative fusion, without the need for a bifocal at near and without overcorrection at distance.