Factors of Surgical Success with Unilateral Recession and Resection in Intermittent Exotropia

ABSTRACT

PURPOSE: To investigate the factors associated with surgical success in cases of unilateral medial rectus resection and lateral rectus recession in the intermittent exotropia. METHODS: Ninety-eight patients with basic-type intermittent exotropia were included in this study. They underwent unilateral recession of the lateral rectus and resection of the medial rectus muscle and were followed postoperatively for at least one year. Surgical results were analyzed to assess the association with preoperative factors, including the angle of deviation, difference of deviation between near and far, stereoacuity at far using B-VAT(R), and Worth 4 dot test (W4DT) at near, and postoperative factors, including the position at near and far at one week, stereoacuity at far using B-VAT(R) at one year, and W4DT at near and far. Surgical success was defined as esotropia within 5 prism diopters (PD) at near and far or within 10PD at near and far at one year postoperatively. RESULTS: Patients with a preoperative difference of deviation between near and far within 5PD had a better surgical outcome than patients with 6~10PD (p=0.03). There was a statistically significant relationship between position at one week postoperatively (especially esotropia or orthotropia at near and far) and success ratio (p0.05). CONCLUSIONS: The difference of preoperative deviation between near and far within 5PD and within 5PD esotropia and orthotropia at near and far at one week postoperatively were significantly associated with a good surgical outcome and could be good prognostic indicators.