title: Hemifacial spasm in childhood and adolescence.
abstract: Hemifacial spasm (HFS), a hyperactive dysfunction of the facial nerve, is rarely seen in young people. Between 1984 and 1994, we treated 924 patients with HFS by microvascular decompression at our institution. Of these, 8 (0.9%) were younger than 30 years. In most of the older patients with HFS, the offending artery which compresses the root exit zone was elongated, redundant, and focally arteriosclerotic as a result of hemodynamic effects due to aging or hypertension. On the other hand, the offending artery did not exhibit such characteristic changes of the vasculature in children and adolescents with HFS. In all of the young patients who underwent initial microvascular decompression at our clinic, the arachnoid membrane around the facial nerve was thickened and encased the artery, resulting in compression of the root exit zone of the facial nerve. Such thickening of the arachnoid surrounding the offending vessel may play an important role in the pathogenesis of HFS by trapping and encasing the artery to compress the root exit zone, particularly in the young patients.
authors.affiliation: Department of Neurosurgery, Kitano Medical Research Institute and Hospital, Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kobata
authors.forename: A
authors.initials: A
authors.lastname: Kondo
authors.forename: Y
authors.initials: Y
authors.lastname: Kinuta
authors.forename: K
authors.initials: K
authors.lastname: Iwasaki
authors.forename: T
authors.initials: T
authors.lastname: Nishioka
authors.forename: K
authors.initials: K
authors.lastname: Hasegawa
mesh_terms: D000293:Adolescent; D000328:Adult; D001099:Arachnoid / Q000601:surgery; D001158:Arteries / Q000601:surgery; D002531:Cerebellum / Q000098:blood supply; D002648:Child; D005152:Facial Muscles / Q000294:innervation*; D005155:Facial Nerve Diseases / Q000209:etiology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008866:Microsurgery; D009408:Nerve Compression Syndromes / Q000209:etiology / Q000601:surgery*; D013035:Spasm / Q000209:etiology / Q000601:surgery*; D013126:Spinal Nerve Roots / Q000601:surgery