Superior Rectus Transposition With Medial Rectus Recession Versus Medial Rectus Recession in Esotropic Duane Retraction Syndrome

Superior Rectus Transposition in the Management of Duane Retraction Syndrome: Current Insights

Various surgical approaches have been described for the management of Duane retraction syndrome (DRS), a type of congenital cranial dysinnervation disorder (CCDD), the goals of which include correcting the primary position deviation and abnormal head posture (AHP), minimizing globe retraction and overshoots and improving the ocular rotations. Vertical rectus transposition (VRT) is one such technique, found more effective in improving abduction and thereby expanding the field of binocular vision, as compared to horizontal muscle surgery. VRT, however, is associated with the risk of inducing vertical deviations and also poses a risk for development of anterior segment ischemia. To overcome these concerns, transposition of only the superior rectus to the lateral rectus was proposed and evaluated to reveal improvement in alignment, AHP and motility comparable to VRT but with lesser surgical time and fewer post-operative complications. With promising results in the management of DRS, superior rectus transposition (SRT) has been extensively studied and has evolved over the last decade with several modifications to further increase the efficiency and reduce the risk of post-operative complications. This article focusses on the pre-operative considerations while planning SRT in DRS, various approaches and surgical techniques described, and the outcomes and complications of SRT in DRS. The role of SRT in the management of other CCDDs may be explored with further studies.

Strabismus Surgery Outcomes and Their Determinants in Patients with Chronic Sixth Nerve Palsy

PURPOSE

Patients with chronic sixth nerve palsy (CSNP) comprise a heterogeneous population, and the optimal surgical solution remains uncertain. Here, we present the success rate and factors associated with the success of strabismus surgeries for CSNP.

METHODS

This was a retrospective cohort study of patients with strabismus due to CSNP operated on between 2015 and 2019 in a tertiary eye hospital in central Saudi Arabia. Surgical success was defined as a horizontal deviation of ≤10 prism diopters (PDs) assessed at least 12 months after surgery. Differences between groups with respect to the primary outcome were assessed.

RESULTS

Fifty-five patients were analyzed with a median follow-up of 24 (range 12-48) months. Superior rectus and inferior rectus transposition (34.5%) and medial rectus recession with lateral rectus resection (32.7%) were the main surgeries performed. The overall success rate was 67.3% (95% confidence interval 54.9-79.7). Bilateral CSNP (P = 0.05), a higher preoperative angle of deviation (P = 0.002), or a greater degree of preoperative limitation of abduction (P = 0.012), but not the type of surgery (P = 0.09), were more likely to result in an under-corrected outcome of >10 PD. The preoperative deviation angle showed a trend toward being associated with a poor outcome after surgery (P = 0.06). Six patients with high-angle deviation before surgery required second surgery.

CONCLUSION

While the surgical procedure does not impact outcomes, the severity of preoperative horizontal deviation might impact surgical success and the need for reoperation. Patients with severe CSNP should be counseled appropriately about the chances of surgical success and the potential need for further interventions.