[The treatment of hemifacial spasms using botulin].

At the Academic Medical Center of the University of Amsterdam the results of treatment of hemifacial spasms (HFS) with botulinum toxin type A were evaluated in a pilot study. Five men and 21 women with HFS were treated with toxin injections. The mean age was 65 years. Most patients were referred from other centers and had been previously treated without success with various medications or with surgical treatment. Treatment took place at the outpatient department. The toxin was injected into the M. orbicularis oculi at the medial and lateral sides of the upper and lower lids. The total dose varied between 6 and 16 LD50. Patients were reinjected on demand. All patients except for one reported satisfying improvement of their spasm. The onset of the beneficial effect was 1-2 days after the injection and the effect lasted about 3 months. All patients were re-examined 1 to 2 weeks after each treatment and showed reduction or disappearance of synkinesias. No systemic side effects occurred and local complications were mild and transient. We conclude that local injection of botulinum toxin appears to be a successful alternative in the current treatment of hemifacial spasm.