Graded unilateral supramaximal medial rectus recession for moderate angle esotropia.

Background and purpose: Recession of a single medial rectus muscle may be appropriate for certain cases of esotropia. However, the procedure has not been widely accepted nor widely studied, and most reports have dealt with conventional recessions (3.5-6 mm) for small angle esotropia. We reviewed our patients who underwent unilateral supramaximal (6-8 mm) medial rectus recession for both small and medium angle esotropia.

Design: Observational case series.

Methods: The records of 56 consecutive patients, undergoing single eye muscle surgery for esotropia, ranging in age from 1 to 11 years were selected and analyzed. All patients had a constant esotropia, despite full cycloplegic refractive correction, measuring 15-40 prism diopters (mean=25.82) at distance and 18-45 prism diopters (mean=30.71) at near. Each patient underwent a graded unilateral medial rectus recession of 6-8 mm.

Results: 48/56 (86%) patients achieved "successful" binocular motor alignment (defined as 0-8 prism diopters residual esotropia at the most recent postoperative visit with a minimum of 5 months and an average of 32 months postoperative followup). The average unilateral medial rectus recession performed was 7.4 mm. Five patients (9%) were overcorrected, (defined as any amount of consecutive exodeviation).

Conclusion: Unilateral supramaximal medial rectus recession appears to be a safe and effective treatment for medium angle non-accommodative esotropia, and has advantages for both patient and surgeon.