Hemifacial spasm: results of microvascular relocation.

Twenty patients with hemifacial spasm were treated between February 1980 and June 1981. All presented with typical disabling unilateral contractions of the face. Computerized Tomographic Scan and angiograms ruled out structural mass lesions. All patients underwent posterior fossa microsurgical relocation of a vessel from the root entry zone of the facial nerve. An offending arterial loop was found in each case. Nineteen patients are free of symptoms and the remaining one is improved. One patient has permanent loss of hearing and two developed mild facial weakness. There has been no recurrence in 18 months follow up. These results given further support to the theory that hemifacial spasm is an affliction of the seventh nerve in the cerebello-pontine angle, most commonly caused by vascular cross compression at the root entry zone. Surgical relocation of the offending vessel relieves the symptoms and there appears to be no recurrence. This procedure is not difficult and carries acceptable risk for the patient with this disabling condition.