Botulinum toxin injection without electromyographic assistance

Area of Science:

• Ophthalmology
• Pediatric Strabismus Surgery
• Neurotoxin Applications

Background:

• Infantile esotropia is a common form of strabismus in children.
• Botulinum toxin injections are used to treat medial rectus muscle overaction.
• The necessity of electromyographic (EMG) guidance during these injections is debated.

Purpose of the Study:

• To evaluate if electromyographic (EMG) control is required for effective botulinum toxin injections in the medial rectus muscles of pediatric patients under sedation.
• To assess the impact of EMG guidance on ocular alignment and postoperative complications.

Main Methods:

• A consecutive series of 40 neurologically normal children (6-48 months) diagnosed with essential infantile esotropia were included.
• Botulinum toxin (7 IU) was injected into both medial rectus muscles under sevoflurane sedation without EMG guidance.
• Postoperative assessments for tropia, paralysis, and complications were conducted at 3 days, 3 weeks, 3 months, and 6 months.

Main Results:

• The mean postoperative esotropia at 6 months was 8.47 prism diopters.
• 53% of patients achieved an esotropia between 0 and 10 prism diopters.
• Common complications included ptosis (23%) and vertical deviation (21%); conjunctival hemorrhage occurred in 7%.

Conclusions:

• Botulinum toxin injections without electromyographic (EMG) guidance yield comparable results to those with EMG in treating congenital esotropia.
• Avoiding EMG guidance may reduce anesthetic risks in pediatric patients.
• The study advocates against the routine use of EMG guidance for botulinum toxin injections in congenital esotropia.