Outcomes for maximal bilateral lateral rectus recession in large-angle exotropia

Area of Science:

• Ophthalmology
• Strabismus Surgery
• Pediatric Ophthalmology

Background:

• Large-angle exotropia presents surgical challenges.
• Maximal bilateral lateral rectus muscle recession (10 mm) is a surgical technique evaluated for this condition.

Purpose of the Study:

• To evaluate the short-term surgical outcomes of patients with large-angle exotropia (≥50 prism diopters).
• To compare outcomes between large-angle exotropia (50-64 prism diopters) and very large-angle exotropia (≥65 prism diopters).

Main Methods:

• Retrospective study of 22 patients undergoing maximal bilateral lateral rectus muscle recession (10 mm).
• Patients were divided into large-angle (50-64 prism diopters) and very large-angle (≥65 prism diopters) exotropia groups.
• Exclusion criteria included prior eye muscle surgery, neurologic deficits, and three- or four-muscle surgery.

Main Results:

• The large-angle group (n=11) had a 75% success rate, while the very large-angle group (n=11) had a 16.7% success rate (P=0.02).
• Undercorrection rates were 18.7% in the large-angle group versus 83.3% in the very large-angle group (P=0.01).
• Mean postoperative exodeviation at distance was 3.7 prism diopters in the large-angle group and 28.0 prism diopters in the very large-angle group (P=0.001).

Conclusions:

• Maximal bilateral lateral rectus muscle recession (10 mm) yields good outcomes for large-angle exotropia (50-64 prism diopters).
• Alternative surgical techniques may be more suitable for exotropia of 65 prism diopters or greater.