BINOCULAR FIELD EXPANSION IN ADULTS AFTER SURGERY FOR ESOTROPIA

Objectives: To determine how frequently adults with longstanding esotropia will experience an expansion of their binocular visual field after surgical correction of their strabismus and to determine if the postoperative expansion of binocular fields in esotropic adults correlates with the type of esotropia (infantile vs acquired), duration of the deviation, visual acuity in the deviating eye, or a history of satisfactory alignment in early childhood. Design: Preoperative and postoperative binocular visual fields were measured in a consecutive series of 37 adults undergoing surgery for esotropia. The fields were obtained and graded by masked observers. Results: Before surgery, all patients had a constricted binocular field on the side of the deviating eye. In 35 of the 37 patients, the visual fields met predetermined criteria for accuracy and were included in data analysis. After surgery, 34 of those 35 patients experienced an expansion of their binocular field consistent with the degree to which the eye was surgically straightened. There was no correlation with binocular field expansion after surgery and the type of esotropia (infantile vs acquired), duration of the deviation, visual acuity in the deviating eye, or a history of satisfactory alignment in early childhood. Conclusions: Binocular field expansion occurs in the vast majority of esotropic patients after strabismus surgery if the surgery is successful in correcting esotropia. The developmental gains that are reported in infants undergoing surgery for infantile esotropia may be due to an expansion of their binocular field after surgery.