Management of Nonresolving Consecutive Exotropia Following Botulinum Toxin Treatment of Childhood Esotropia

OBJECTIVE: To study motor and sensory results of surgery for exotropia following botulinum toxin A injection to correct childhood esotropia. METHODS: The medical records of 2445 patients treated with botulinum toxin bimedial injection were retrospectively reviewed to select patients operated on after 1 year of consecutive exotropia. We recorded age at onset of deviation, retinoscopic refractive error, visual acuity and age and dosage at the time of botulinum toxin injection. Retinoscopic refractive error, visual acuity, deviation angle, and stereoacuity before surgery for consecutive exotropia were also recorded. Families were contacted to obtain retinoscopic refraction, visual acuity, deviation angle, Bagolini test, vectography, and stereoacuity data 1 to 8 years after surgery. RESULTS: A total of 5 children with acquired esotropia and 2 with infantile esotropia were included. A high dose of the toxin per injection might increase the risk of consecutive esotropia. Preoperative mean exotropic deviation was 15.42 prism diopters (PD) (range, 10-25 PD), and stereoacuity was not measurable before surgery. Postoperative mean deviation was 6 PD (range, 4-8 PD), and mean stereoacuity was 447.14 arc seconds. In 2 patients, suppression of the nondominant eye was detected. Three children had poor stereoacuity. CONCLUSION: Surgery for exotropia following botulinum toxin injection in children is effective from a motor and sensory point of view.