A Comparative Study of Surgical Outcomes between the Adjustable Suture Technique and Conventional Technique in Strabismus Surgery

Abstract

Objective: To compare the success rate between adjustable suture technique and conventional technique in rectus muscle surgery. Materials and Methods: The present study was a retrospective review of patients aged 10 and above underwent rectus muscle surgery between 2010 and 2018. Patients were classified into two groups according to the surgical techniques, the adjustable group and the conventional group. Preoperative and postoperative orthoptic evaluation including angle of deviation, sensory outcomes, and reoperation rate were collected. The primary outcome was surgical success rate at two years postoperatively, with success defined as ocular alignment within 10 prism diopters (PD) for horizontal rectus muscle surgery or within 5 PD for vertical rectus muscle surgery. The secondary outcome was reoperation rate and binocular functions improvement two years post-operation. Results: One hundred fifteen cases in the adjustable group and 90 in the conventional group were identified. Patients in the adjustable group had a higher success rate achieving the target angle after six months, one year, and two years post-operation compared to the conventional group at 77.4% versus 70% (p=0.23), 73.9% versus 65.6% (p=0.19), and 72.2% versus 60% (p=0.066), respectively, but there was no statistically significant difference. Sensory improvement was seen in 43.4% of patients in the conventional group and 42.6% in the adjustable group (p=0.54). Median stereopsis improvement was seen in both groups at 80 to 45 seconds of arc in the adjustable group and 100 to 60 seconds of arc in the conventional group (p=0.67). The reoperation rate was 18.9% in the conventional group and 19.1% in the adjustable group (p=0.97). Conclusion: The adjustable suture technique presented a superior success rate compared to conventional technique though there was no statistically significant difference. A longer follow-up period and larger sample size might be needed to demonstrate statistically significant difference between the two techniques. No significant difference in binocular functions, sensory improvement, or reoperation rate was seen in the present study. Keywords: Strabismus surgery; Adjustable suture; Conventional suture; Surgical outcome