[Efficacy of botulinum toxin in infantile esotropia]

Introduction and objective: Botulinum toxin (BT) is used in a variety of therapeutic applications, including the treatment of strabismus. Two injection techniques coexist - transconjunctival injection and open sky injection. The goal of this study was to evaluate the results of BT injections in esotropia in children under 10 years of age and to compare the two techniques.

Patients and method: This is a retrospective, monocentric study, including children who received BT injections to treat their strabismus by the aforementioned techniques between 2014 and 2017. The results of these injections were recorded, and subgroup analyses (injection technique, age, degree of deviation, type of strabismus) were performed. The primary endpoint was the optimal success rate defined as residual strabismus less than or equal to 10 Δ.

Results: The study included 68 children with a mean age of 28.9 months and a mean deviation angle of 34.7 Δ. Patients received 1.2 BT injections. The success rate was 38% at 6 months, 35% at 12 months, and 35% at 24 months. There was 33% transient ptosis and 5% consecutive exotropia. There was no evidence of significant difference in success rate between the transconjunctival and open sky injection methods, baseline angles, age of injection, or type of strabismus.

Conclusion: BT injection is effective and safe in pediatric esotropia, regardless of the injection method.