Postoperative outcomes in children with intermittent exotropia from a population-based cohort

Purpose: To describe the long-term surgical outcomes in a population-based cohort of children with intermittent exotropia. Methods: The medical records of all children (<19 years) who were diagnosed with intermittent exotropia as residents of Olmsted County Minnesota, from January 1, 1975, through December 31, 1994, and managed with surgery were retrospectively reviewed. Results: Of 184 patients with intermittent exotropia, 61 (33%) underwent surgery at a mean age of 7.6 years (range, 3.2 to 23 years). Twelve of the 61 children (19.7%) underwent a second surgery (10 for recurrent exotropia and 2 for consecutive esotropia), and no patient received 3 or more surgeries during a mean follow-up of 10 years from the first surgery. The final postoperative measurements were recorded in 56 of 61 patients (92%) at a mean of 7.4 years (range, 0 to 18 years) after the first surgery: 31 of the 56 (55%) were within 9^Δ of orthotropia at distance and 25 of 55 (45%) had better than 60 seconds of stereopsis. The Kaplan-Meier rate of developing ≥10^Δ of misalignment after the first surgery was 54% by 5 years, 76% by 10 years, and 86% by 15 years. Conclusions: In this population-based study of surgery in children with intermittent exotropia, although only 1 in 5 received a second surgery, after a mean follow-up of 8 years, approximately half were successfully aligned and 45% had high-grade stereopsis.