Continuous facial myokymia in multiple sclerosis: treatment with botulinum toxin

Continuous facial myokymia (CFM) is an involuntary undulating, vermicular movement that spreads across facial muscles and is associated with a characteristic electromyographic pattern. It is an infrequent clinical sign that almost always occurs in intrinsic brainstem lesions, particularly in multiple sclerosis (MS). It is usually present for only a few weeks, but it may persist for long periods of time being very troublesome for patients. We report 2 cases with MS and continuous hemifacial myokymia persisting for up to 1 month which disappeared after injection of botulinum toxin. Botulinum toxin A (BTX-A) has been used successfully to treat a variety of focal dystonias and occasionally in orbicularis myokymia, but its use has not been reported in continuous hemifacial myokymia. BTX-A appears to be effective and safe for treating persistent facial myokymia in MS patients.