[Treatment of strabismus associated with psychomotor impairment using botulinum toxin]

Strabismus is associated with 80% of people with psychomotor retardation. Surgical treatment is difficult owing to brain instability. The aim of this study is to determine the efficacy of a direct application of botulinum toxin in cases strabismus related to psychomotor retardation.

This is a retrospective, longitudinal, observational study of treatment of strabismus associated to brain damage (under the Laws of Health of Mexico) using a direct application technique of botulinum toxin, considering age, type of strabismus, number of toxin applications, response and cause of brain damage.

We analyzed 30 patients, age: 3.5 years old (S.D.: 2), follow-up 12.7 (S.D.: 2.3 months). Eighty percent of the patients had moderate psychomotor retardation and 20% had a severe retardation. The response was good in 44% and moderate in 24%, there were no cases without response. The patients were treated with 1.7 (S.D.:1) injections of toxin. Age and type of strabismus was not related to success of treatment (X2: 9.4; 7.8 to null hypothesis). First application of toxin determines the response to treatment (Fisher test: <0.05). Moderate retardation was related to better response. Bad results were related to unstable brain disease.

The difficulty and prognosis of surgical treatment of strabismus in patients with brain damage and psychomotor retardation, causes us to consider the use of botulinum toxin as the first choice for this cases.