Changes in Lateral Comitance After Asymmetric Horizontal Strabismus Surgery

Area of Science:

• Ophthalmology
• Surgical Innovation
• Strabismus Management

Background:

• Horizontal strabismus surgery often prioritizes primary gaze alignment.
• Surgical choices can impact side gaze alignment, potentially causing functional and social issues.

Purpose of the Study:

• To identify surgical procedures linked to changes in side gaze alignment.
• To inform surgical planning for horizontal strabismus patients.

Main Methods:

• Retrospective review of 1081 horizontal strabismus surgeries.
• Inclusion of records with pre- and post-operative strabismus measurements in right and left gaze.
• Analysis of change in comitance (CIC) using horizontal comitance measurements.

Main Results:

• Asymmetric surgery was associated with new postoperative incomitance in 89.9% of previously comitant patients.
• Asymmetric 2-muscle surgery resulted in a significantly higher median CIC (4.0) compared to symmetric surgery (1.5).
• Symptomatic new incomitance occurred in 28.8% of patients following asymmetric surgery.

Conclusions:

• Asymmetric strabismus surgery can correct existing incomitant deviations but may induce new symptomatic ones.
• Surgical planning must consider the potential for change in comitance (CIC) and its impact on side gaze.
• Careful consideration of asymmetric surgery consequences is vital for patients with binocular vision to prevent diplopia.