Clinical Course and Outcome of Infantile Exotropia

Purpose: To evaluate the clinical course and surgical outcome of infantile exotropia with large and constant angle, as defined by the onset of exotropia before 6 months. Methods: We reviewed the records of 11 patients who were diagnosed with infantile exotropia and received surgery between July 1987 and December 2003. Age at onset and surgery, visual acuity, refractive error, preand post-operative angle of strabismus, and binocular sensory status after surgery were evaluated for each patient. Results: The mean age at onset, diagnosis, and first surgery was 2.3 months (range, birth to 5 months), 14.9 months (range, 4 to 33 months), and 36.3 months (range, 11 to 45 months), respectively. The mean size of preoperative exodeviation was 57.3 prism diopters (PD) (range, 40 to 100 PD). Six patients (54.5%) required reoperation to correct residual or recurred exotropia, oblique dysfunction, and/or DVD. Two (18.2%) of the six required a third operation. Sensory tests including Lang test were performed in seven patients but all failed in Lang test and showed no fusion even with successful surgical treatment. Conclusions: Infantile exotropia should be observed for a long period and needs proper reoperation because it may be frequently associated with residual or recurred exotropia, oblique dysfunction, and/or DVD after initial operation. However, improvement of binocular function can rarely be expected even with successful surgical alignment.