Augmented surgical amounts for intermittent exotropia to prevent recurrence

PURPOSE: The purpose was to evaluate the results of bilateral lateral rectus (BLR) recession which is based on augmented surgical amounts of classical surgical table of Parks’ for basic and pseudo-divergence excess type intermittent exotropia [X(T)]. MATERIALS AND METHODS: Patients with X(T) operated by the same surgeon and followed-up for at least 6 months were included. Patients with prior surgery, neurobehavioral and musculoskeletal conditions, strabismus different from that mentioned above X(T) were excluded. All the patients received BLR only. The amount of the recession was increased by the amount needed to correct 5 prism diopters (PD) more X(T) than what was measured. After the operation, 1(st) week, 2(nd) and 6 months measurements were recorded. The patients were grouped according to their 1(st) week (3–7 days) postoperative examination as: >10 PD esotropia (Group 1), ≤10 PD esotropia (Group 2), exotropia (Group 3), and orthotropic (Group 4), respectively. Final surgical outcomes were classified as “good” (≤10 PD exotropia and ≤5 PD esotropia), “recurrence” (>10 PD exotropia) and “overcorrected” (>5 esotropia). RESULTS: Thirty-seven patients were included. The mean age was 6.78 ± 2.87 years (range: 2–12 years). Mean preoperative deviation was 29.72 ± 8.07 PD (range: 15–45 PD) at distance and 20.94 ± 11.65 PD (range: 10–45 PD) at near (P < 0.0001). There were 21 (56.8%) patients in Group 1, 9 (24.3%) patients in Group 2, 1 (2.7%) patient in Group 3 and 6 (16.2%) patients in Group 4. Initial esotropia was achieved in 30 (30/37) of the patients. Twenty-eight of them had good results at the end of the 6 months. Overall “motor surgical” success rate was found to be 89.2% (33/37 patients), with 1 (2.7%) overcorrection and 3 (8.1%) recurrences at the end of the 6 months. CONCLUSION: This study demonstrated that early overcorrection of 10–20 PD after X(T) surgery can achieve acceptable motor outcomes in the first 6 months postoperative period.