Purpose: To ascertain whether electromyographic control of the muscles when injecting botulinum toxin in the medial rectus muscles of children under sedation is necessary to obtain good results in terms of ocular alignment and postoperative complications.
Methods: Forty neurologically normal children 6 to 48 months of age were entered consecutively into the study once the initial diagnosis of essential infantile esotropia had been made. The children were sedated with sevoflurane and both medial rectus muscles were injected with 7 IU of botulinum toxin using an insulin syringe with a 27-gauge needle. Postoperative controls were performed at 3 days, 3 weeks, 3 months, and 6 months after the injection. The effectiveness of the injection was noted in terms of tropia, paralysis, and associated complications.
Results: The mean tropia at 6 months postoperatively was 8.47 prism diopters of esotropia, ranging from 25 prism diopters of esotropia to 10 prism diopters of exotropia. Fifty-three percent of the patients had an esotropia between 0 and 10 prism diopters. The most common complications were ptosis and vertical deviation, affecting 23% and 21% of the patients, respectively, followed by conjunctival hemorrhage, which was recorded in 7% of the patients. There were no retrobulbar hemorrhages, ocular perforations, or anesthetic complications.
Conclusions: If anesthetic risks are higher and the results are similar when using electromyographic control, we advocate not using it in congenital esotropia when injecting botulinum toxin in children.