Comparison of Conventional Hang-Back Technique With Modified (Anchored) Hang-Back in Medial Rectus Recession: A Retrospective Study

TL;DR

This study compares two surgical techniques for treating eye misalignment and finds similar success rates but different complication risks.

Contribution

A direct comparison of conventional and modified hang-back techniques in medial rectus recession for esotropia.

Findings

Both techniques had similar surgical success rates at final follow-up.

Modified HBT had a higher rate of consecutive exotropia development.

Reoperation rates were low and not significantly different between the two groups.

Abstract

Purpose: To assess the efficacy of the modified hang-back technique (HBT) in comparison to conventional HBT. In this study, we have compared the two techniques in treating esotropia in terms of surgical success, development of consecutive exotropia, and the need for reoperation.

Method: A retrospective medical record review of all patients who underwent bilateral medial rectus recession (BMR) between January 2016 and December 2020, with modified HBT or conventional HBT at our institution by four strabismologists. Angles of deviation were measured preoperatively, at one week, at 6-12 weeks, and at final follow-up postoperatively. We evaluated surgical success (alignment within 10 prism diopters [PD] of orthotropia) and complications such as the development of consecutive exotropia and the need for reoperation.

Results: The record review identified 103 patients who underwent BMR: 83 in modified HBT vs. 20 in conventional HBT. The overall success rate at final follow-up was similar between the two groups: the success rate in the conventional HBT group was 83.3% (median interquartile range [IQR]) follow-up months 11.0 (6.0-12.8) compared to 72.6% (median IQR) follow-up months 12.0 (12.0-20.0) in the modified HBT group (p=0.435). The rate of consecutive exotropia development was higher in modified HBT (4.83%) vs. 0% in conventional HBT. Reoperation was required for two patients in the modified HBT group (2.4%), both for overcorrection, compared to one patient in the conventional HBT group (5%) for undercorrection (p=0.536).

Conclusion: Conventional HBT is a comparable method to the modified HBT in bilateral medial rectus recession for treating esotropia with similar surgical outcomes.