Botulinum injection for the treatment of acute esotropia resulting from complete acute abducens nerve palsy

PurposeThe objective of this study was to investigate the effectiveness of botulinum toxin A (BTX-A) injections in the treatment of acute esotropia resulting from complete acute abducens nerve palsy.MethodsFifteen patients treated for complete acute abducens nerve palsy in our clinic were retrospectively reviewed. All patients who experienced an onset within 3 months and who were treated with early subtenon BTX-A injections at the ipsilateral medial rectus muscle without electromyography (EMG) guidance were included in this study. Responses and complications were recorded during a follow-up of at least 6 months.ResultsThirteen patients who had trauma and two patients who had brain tumor that caused their abducens nerve palsy were enrolled. Overall, six patients (40%) had full recovery and two patients (13%) had partial recovery, but the residual esotropia could be tolerated with prism correction in an average of 14.6 weeks. Seven patients (47%) received strabismus surgery afterward. Patients who did not respond well to early BTX-A injections at the 1-week interval were prone to subsequent surgical intervention (p = 0.026). Three eyes (20%) had transient subconjunctival hemorrhage following the subtenon space injection; no other complications were found after the treatment.ConclusionBTX-A offers patients with complete abducens palsy a possible better chance to regain binocular vision and indicates whether additional surgical interventions are needed for these patients. We also discovered that the subtenon space injection of BTX-A without EMG guidance was a safe, time-saving, and simple technique.