Why bilateral medial rectus recession fails? Factors associated with early repeated surgery

To explore the risk factors for failure of bilateral medial rectus muscle recession (BMR) for esotropia.

We reviewed 171 consecutive patients with esotropia who underwent bilateral medial rectus muscle recession as a primary procedure from January 2009 to December 2011. Patients with infantile, partially accommodative and acquired esotropia were included. We compared patients who required more than one surgery to patients who only had one operation.

A total of 171 patients (89 males, 52%, mean age 5.1 ± 6.0 years, range 0.4-51 years) fulfilled the inclusion criteria and comprised the study population. Mean follow-up period was 17.4 ± 15.5 months (range 1-65 months). A second strabismus surgery was performed in 17 (9.9%) cases within a mean time of 11.7 ± 9.2 months (range 0.4-27.7 months) from the initial surgery. Univariate analysis demonstrated that in patients younger than 1 year the odds ratio (OR) of failure was 4.00 (95% CI 1.12-14.35, p = 0.033) and for patients older than 7 years the OR of surgical failure was 3.27 (95% CI 1.10-9.76, p = 0.033). In addition, patients with esotropia > 60 prism diopters (PD) had a trend towards needing further surgery (OR = 3.91, 95% CI 0.93-16.44, p = 0.063). A multivariate model of regression revealed that age and angle of esotropia > 60 PD remained significant risk factors for requiring additional surgeries.

In our cohort of patients who underwent BMR for esotropia, a large angle of esotropia and age were associated with failure of surgery and need for reoperation.