Purpose: To define the prevalence and time course of significant changes in angle of deviation during the first months after the diagnosis of infantile esotropia and to determine whether long-term alignment and sensory outcomes differ when surgical alignment is performed on infants with stable vs unstable angles of deviation.
Design: Prospective cohort study.
Methods: setting: Institutional and clinical practice. patient population: Newly diagnosed patients with infantile esotropia (N = 208). observation procedure: Preoperative measurements of the angle of deviation on the initial visit and at approximate six-week intervals until surgery was performed. main outcome measures: Ocular alignment at six weeks, one year, and four years postoperative and stereoacuity at age five to nine years.
Results: Overall, 57% of infants had an esodeviation on the second visit that was within 10 prism diopters (p.d.) of the deviation measured on the initial visit (stable group), 33% had an increase of 10 p.d. or more (unstable group), and 11% had a decrease of 10 p.d. or more. Among the 127 patients with additional preoperative visits, many switched between the stable and unstable categories during follow-up. Long-term, stable and unstable preoperative alignment groups had similar postoperative motor alignment, re-operation rates, rates of prescription of hyperopic, or bifocal spectacle correction and stereoacuity.
Conclusions: It may not be necessary to wait for a "stable" angle of esodeviation before surgery since both alignment and sensory outcomes were similar for stable and unstable groups.