Radiological analysis of hemifacial spasm with special reference to angiographic manifestations.

Fifty-one patients with hemifacial spasm secondary to facial nerve compression by normal appearing, elongated, tortuous and/or dilated arteries, were treated by microsurgical neurovascular decompression. Post-operatively, 91% of 44 of these patients with one to six year postoperative follow-ups were satisfactory. The angiographic findings showed significant increase in the number of common trunk anomalies. Variations of the anterior and posterior inferior cerebellar and vertebral arteries are discussed in relation to nerve compression.