Treatment of congenital esotropia with botulinum toxin type A

Abstract. Purpose: To examine the effect of botulinum toxin type A injections given transconjunctivally into the medial recti muscles in patients with congenital esotropia. Methods: Eighty-two patients with congenital esotropia were treated with botulinum toxin type A transconjunctival injections into the medial recti muscles. Results: A Kaplan-Meier curve shows a 24-month success rate of 87% (n = 53) with alignment within 20 prism dioptres (PD) of the 80 patients who were seen at least 1 year following the last injection. Seven of the 80 patients underwent standard monocular surgery with recession of the medial rectus and resection of the lateral rectus muscle. Two patients were lost during follow-up. Conclusion: Botulinum toxin type A injections into the medial recti muscles are a valuable alternative to conventional strabismus surgery.