In this prospective study, botulinum toxin A was injected into 28 patients diagnosed with strabismus. Data were obtained from the records of patients that were evaluated during 2013 in the Strabismus Unit of Rey Juan Carlos Hospital (Móstoles, Madrid, Spain) in order to assess the indications and dosage of botulinum toxin A use in strabismus, as well as its clinical effect and differences in pediatric and adult patients. The outcomes in the last visit, at least 14 months after the injections, were analyzed.
An analysis was performed on the data from 11 children, 6 females (54.5%), and 17 adults, 11 males (64%). The mean age was 4.42 ± 3.48 years and 58.71 ± 18.07 years in the children and adult groups, respectively.
The majority of cases in both groups were esotropia (81.8% in children and 47.1% in adults). However, the pathologies in the adult group were quite heterogeneous, including four patients with exotropia (26.5%), four with hypertropia (26.5%), and one with isolated nystagmus (5.9%).
The mean number of the botulinum toxin injections in children was 1.45 ± 0.93, although 72.7% received a single injection. In the adult group, the mean number of injections was 3.27 ± 1.41.
There was a statistically significant difference between pre- and post-injection in the tropia and phoria measurements in children and adults group (
An improvement in the stereoacuity could be detected in four children.
Two children (18.2%) and five adults (29.4%) required subsequent surgical intervention.
Eight adult patients (49.1%) complained of diplopia in the primary position, which was resolved in six cases with toxin injection, whereas two needed surgery for diplopia correction.
Botulinum toxin is a very useful tool in the management of strabismus, obtaining better sensory and motor results in children, but it is also effective as a symptomatic treatment in some types of strabismus in adults.