Convergence Insufficiency After Bilateral Medial Rectus Recession For Age-Related Distance Esotropia?

Purpose: This study evaluated postoperative exophoria and symptoms of convergence insufficiency following bilateral medial rectus (MR) muscle recession performed for correction of age-related distance esotropia (ARDE). Design: Retrospective case series. Methods: Data were reviewed for patients with ARDE without neurological diseases who underwent bilateral MR recession between September 2014 and October 2024. Results: Included were 110 patients of mean age 74±9 (standard deviation) years. Preoperative esotropia was 13±8∆ at distance and 4±6∆ at near. Pre-operative convergence fusional amplitude was 27±12∆. Bilateral MR recession was combined with vertical rectus surgeries in 28 (25%) patients. At the final follow-up after a mean of 14 months, 8 (7%) patients exhibited exophoria at distance. Exophoria was present at near in 48 (44%) patients, including 8 in whom exophoria exceeded 10∆. However, none of these exophoric patients reported symptomatic diplopia or difficulty with near tasks at any time. At final follow-up ARDE recurred in 22 patients (20%). Mean initial postoperative near deviation did not differ between groups (-2.0∆ vs. -2.4∆, P = 0.77). However, at final follow-up, the non-recurrence group had significantly more exophoria than the recurrence group (-2.5∆ vs. -0.1∆, P = 0.02). Survival analysis demonstrated approximately 15% recurrence rate of ARDE 2.5 years after surgery, increasing at 5 years postoperatively to 40%. Conclusion: Bilateral MR recession for ARDE is unlikely to cause convergence insufficiency, but long-term postoperative exophoria after this procedure may protect against late recurrence of ARDE.