Use of botulinum toxin injections to treat peripheral stimulator induced facial muscle twitching: a case report

Background: Facial pain can be a management challenge. Peripheral nerve/field stimulation may be an effective option for refractory cases, but direct muscle stimulation with facial twitching may result. Botulinum toxin injections have been used for blepharospasm and may be effective when facial stimulation results in unacceptable facial muscle twitching due to peripheral stimulation. Case presentation: A 53-year old female suffered with chronic, refractory facial pain and migraines. Her facial pain began after a root canal of a left upper molar. She was trialed and then permanently implanted with a 1 x 8 sub-compact percutaneous stimulator lead, resulting in improved pain control and reduced medication use. However, she experienced blepharospasm whenever the amplitude was above 2.75 A. Therefore, she was treated with botulinum toxin injections into her bilateral cheek, face, temple and occiput. This treatment provided excellent relief of the facial spasms, allowing her to use her stimulator at high amplitudes, and thereby maximizing her pain relief. She received two subsequent treatments of botulinum toxin injections at 5-month intervals with similar results. Conclusion: Peripheral nerve/field stimulation is being used for headaches and facial pain. An undesirable side effect of this emerging therapy is direct muscle stimulation. Botulinum toxin injections may be an effective treatment modality when stimulation techniques provide pain relief but also causes muscle twitching.