IPoster: A Randomized Trial Comparing Bilateral Lateral Rectus Recession versus Unilateral Recess-Resect for Basic Type Intermittent Exotropia

Purpose: To evaluate whether bilateral lateral rectus recession (BLRc) or unilateral recess-resect (R/R) surgery results in better outcomes for intermittent exotropia (IXT) in children.

Methods:197 children age 3- < 11 years with basic-type IXT and near stereoacuity of 400 arc-seconds or better, were randomized to BLRc or R/R. The primary outcome measure was the cumulative probability of "suboptimal surgical outcome," defined as exotropia ≥ 10Δ or constant esotropia ≥ 6Δ at distance or near by simultaneous prism & cover test, or decreased stereoacuity of ≥2 octaves from baseline, at ANY 6-month masked examination from 6 months to 3 years after surgery. Reoperation was allowed by protocol only after meeting suboptimal outcome criteria; however, when reoperation was performed without meeting criteria, it was considered a suboptimal surgical outcome for analysis.

Results: The cumulative probability of suboptimal surgical outcome was 45.9% (43 of 101) and 37.3% (33 of 96) in the BLRc and R/R groups, respectively (difference = 8.6%; 95% CI, -5.8% to 23.0%). Reoperation by 3 years occurred in 9 (9.8%) BLRc subjects (8 met suboptimal outcome; 1 did not) and in 4 (4.6%) R/R subjects (3 met suboptimal outcome; 1 did not) (difference = 5.2%; 95% CI, -2.3% to 12.7%).  Among those with a full 3 years of follow up, 29.1% (25 of 86) and 16.9% (13 of 77) in the BLRc and R/R groups, respectively, met suboptimal surgical outcome criteria at the 3-year visit (difference = 12.8%; 95% CI, -2.8% to 28.0%); this lower rate is primarily because several subjects with suboptimal outcomes at earlier visits did not meet the criteria at 3 years.

Conclusion(s): There was no statistically significant difference in suboptimal outcomes by 3 years after surgery between children with IXT treated with BLRc compared with R/R. Both procedures are reasonable approaches when surgery is the treatment for childhood IXT.

Angela Chen, OD, MS, FAAO

Dr. Angela Chen is currently an assistant professor at the Southern California College of Optometry at Marshall B. Ketchum University. She does didactic and clinical teaching in the Pediatric Vision and Vision Therapy department.  Dr. Chen is a fellow of the American Academy of Optometry and a diplomate in the Binocular Vision, Perception & Pediatric Optometry Section. Her research interests include strabismus, amblyopia, and non-strabismic binocular vision disorders. She serves as a clinical investigator in several NEI supported studies for the Pediatric Eye Disease Investigator Group (PEDIG) and the Convergence Insufficiency Treatment Trial-Attention and Reading Trial (CITT-ART).