Pre-operative stability of infantile esotropia and post-operative outcome.

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.