Effect of Botulinum Toxin A Chemodenervation in Sensory Strabismus

Purpose: To study the effect of botulinum toxin type A chemodenervation in sensory strabismus. Methods: Twelve patients with sensory strabismus were treated with an injection of botulinum toxin type A (Botox; Allergan, Irvine, Calif). Botulinum toxin type A was diluted with 0.9% sodium chloride without preservative at a dose that ranged from 1 .25-5 U. A Teflon-coated needle electrode was inserted into the medial reclus muscle in cases of esotropia and into the lateral rectus muscle in cases of exotropia. Four patients were treated with 5=2 injections of botulinum toxin type A. Changes in the angle of strabismus and related complications were followed for >6 months postinjection. Results: The mean deviation before injection was 33.8 prism diopters (?) and the mean corrective effect on the deviation was 72.8% after injection in patients with sensory strabismus. The final deviation in 9 patients was Conclusion: Botulinum toxin type A is likely to prevent muscle contracture and affect muscle and neuronal tissues. This study on the effects of sensory strabismus with botulinum toxin type A injection suggests it has the potential to replace surgery or be used as an adjuvant therapy. Journal of Pediatrie Ophthalmology and Strabismus 2001:38:68-71.