Results of Monocular Surgery Under Peribulbar Anesthesia for Large-Angle Horizontal Strabismus

Abstract

OBJECTIVE: To evaluate the results of monocular surgery under peribulbar anesthesia for large-angle horizontal strabismus. INTRODUCTION: Monocular surgery may preserve some muscles if a repeat operation is required, may help to avoid the exposure of the dominant eye to the inherent risks of a surgical procedure and may reduce surgical time. METHODS: We evaluated ninety-two consecutive patients who underwent monocular surgery under peribulbar anesthesia for large-angle horizontal strabismus (angle of 40 prism diopters or greater). Patients were divided into group 1- esotropia and group 2 -exotropia. The postoperative follow-up was at 6 months, when the residual deviation was evaluated. In cases of residual deviations of over 15 PD (prism diopter), a second procedure was indicated. RESULTS: In all patients with preoperative deviations up to 60 PD, residual deviations were under 15 PD. Some patients with preoperative deviations of 65 PD (two in group 1 and four in group 2) and all patients with deviations over 65 PD had residual deviations over 15 PD. The 13 patients who underwent a second procedure experienced successful outcomes. Our ROC curve analysis showed that the cutoff point for obtaining a successful surgical result was 62.5 PD. No patient presented with a major limitation in respect of ocular movement. CONCLUSIONS: Monocular surgery under peribulbar anesthesia can be an alternative for horizontal large-angle strabismus given deviations of up to 60 PD. Monocular surgery did not result in successful outcomes for deviations of over 65 PD

Outcomes of 3 or 4 Horizontal Muscles Surgery in Large-Angle Exotropia

“…8,9 This study included patients with large-angle exotropia of 50 PD or more who underwent 3 or 4 horizontal rectus muscles surgery. The success rates of this study were 69% at the last follow-up and 75% at the follow-up at 2 years, which were comparable with rates of 62% to 83% in other studies.…”

“…6,7 Monocular surgery is an alternative procedure to avoid surgery in the dominant eye. 8,9 Exotropia tends to recur after strabismus surgery. Initial overcorrections of 0 to 10 PD, 9 4 to 14 PD, 10 or 10 to 20 PD 11 have been recommended to compensate for the postoperative exotropic drift.…”

“…Moreover, the success rate was reported to correlate with preoperative angle of deviation, visual acuity, and age. 7,8,12,13 The primary objective of this study was to evaluate motor and sensory outcomes of 3 or 4 horizontal muscles surgery for largeangle exotropia with a secondary aim to evaluate the influencing factors of the success rate and the relationship between initial postoperative deviation and final motor outcomes.…”

Surgical Outcome of Unilateral Lateral Rectus Recession and Medial Rectus Resection in Large-Angle Exotropia

“…Although, it has been recommended by most authors not to exceed 7 mm medial rectus resection and 8 mm lateral rectus recession in order to avoid ocular movement limitations, 4,20,21 in our study we have done lateral rectus recession of 8 -10 mm and medial rectus resection of 7 -9 mm. None of the patients in our study had significant postoperative restriction of ocular motility.…”

“…But for exotropia of > 60 PD, monocular surgery was not so effective. 4 Therefore, this study was done to evaluate the outcome of single-stage unilateral two muscle surgery for large-angle exotropia (> 60 PD).…”