Strabismus and Strabismus Surgery Reoperation Rates at 1, 3, and 5 Years: Analyses from the IRIS® Registry (Intelligent Research in Sight).

Purpose: To describe strabismus surgery reoperation rates and risk factors for children and adults in the United States.

Design: Retrospective cohort analysis of health care data.

Participants: A total of 79 424 597 patients in the IRIS® Registry (Intelligent Research in Sight).

Methods: Description of strabismus, strabismus surgery, and reoperations from 2013 to 2022. Multivariable models of factors associated with a reoperation within 1 year were developed.

Main outcome measure: Reoperation rates at 1, 3, and 5 years were calculated for strabismus surgeries performed from 2013 to 2017.

Results: A total of 1 951 001 patients (2.46%) had strabismus (2.68% among male patients and 2.29% among female patients, difference = 0.39%, 95% confidence interval [CI], 0.38-0.40; P < 0.001). Diagnoses included esotropia (17.8%), exotropia (21.8%), hypertropia (13.5%), and paralytic strabismus (16.1%). At least 1 surgery was performed in 125 984 patients; 79% of reported codes were for horizontal surgery; 58% of cases were performed in patients aged less than 20 years. Reoperation rates were 5.61% (95% CI, 5.43-5.81), 8.53% (8.30-8.76), and 10.13% (9.88-10.38) within 1, 3, and 5 years, respectively. At each time point, reoperation rates were lowest for children 6 to 19 years of age. In multivariable models, the odds ratio (OR) for a strabismus reoperation within 1 year was lower in non-Hispanic Black or African American patients (0.82, 95% CI, 0.73-0.92) compared with non-Hispanic White patients. The risk for reoperation did not differ between White patients and patients of other races and ethnicities. When compared with Medicare Part B, ORs for a reoperation were lower for patients with commercial insurance (0.72, 95% CI, 0.64-0.80) and Medicaid (0.82, 95% CI, 0.72-0.94). The ORs of a reoperation when compared with the Northeastern United States were significantly lower in the Midwest (0.75), South (0.88), and the West (0.73).

Discussion: Strabismus is uncommonly reported in clinical practice. The odds of undergoing a reoperation after statistical adjustment differed significantly by race and ethnicity, insurance, and region of the United States. Reasons for these differences deserve future inquiry. Reoperation rates generally increased with duration of follow-up for all age groups, suggesting there is an ongoing need for strabismus care for patients of all ages.

Conclusions: These findings may serve as benchmarks for surgical training, measuring physician performance, patient counseling, and development of risk adjustment tools.

Financial disclosure(s): Proprietary or commercial disclosure may be found after the references.