재발된 간헐외사시로 재수술한 환자의 임상분석

The Clinical Analysis after Reoperation for Recurrent Intermittent Exotropia

Purpose: To analyze the clinical course and relationships between the factors and surgical outcomes after reoperation for recurrent intermittent exotropia. Methods: Surgical results were retrospectively investigated in 38 patients who had undergone reoperation at least 3 months after surgical correction. Recurrence was defined as an exodeviation of more than 10 prism diopters at the primary position. We investigated the recurrence rate according to the follow-up duration with survival analysis, and analyzed the relationships between the factors and surgical outcome. Results: The mean survival period was 22.7±20.2 months (range, 3 to 72 months). As the follow-up duration increased, the recurrence rate progressively increased. The hazard ratio for recurrence of a unilateral medial rectus resection as a reoperation was significantly higher than that for a unilateral lateral rectus recession and medial rectus resection (recession and resection)(p=0.021). After using unilateral recession and resection as the primary surgery, the hazard ratio for recurrence of unilateral recession and resection as a reoperation was not significantly different from that for unilateral lateral rectus recession (p=0.480). After a bilateral lateral rectus recession, the hazard ratio for recurrence of unilateral medial rectus resection was not significantly different from that for bilateral medial rectus resection (p=0.076). Conclusions: The surgical options for recurrent intermittent exotropia are contralateral recession and resection or contralateral lateral rectus recession. The procedure chosen depends on the operator`s preference after performing unilateral recession and resection as the primary surgery. After a bilateral lateral rectus recession, the hazard ratio for recurrence of unilateral medial rectus resection was not significantly higher than that for a bilateral medial rectus resection, but even so, a bilateral medial rectus resection may be more effective than unilateral medial rectus resection for recurrent intermittent exotropia.