title: Spasmodic torticollis due to neurovascular compression of the spinal accessory nerve by the anteroinferior cerebellar artery: case report.
abstract: OBJECTIVE
  Spasmodic torticollis is a neuromuscular disorder characterized by uncontrollable clonic and intermittently tonic spasm of the neck muscles. We report a case of spasmodic torticollis attributable to neurovascular compression of the right XIth cranial nerve by the right anteroinferior cerebellar artery (AICA).
  
  
  METHODS
  A 72-year-old man with a 2-year history of right spasmodic torticollis underwent magnetic resonance imaging, which demonstrated compression of the right XIth cranial nerve by an abnormal descending loop of the right AICA.
  
  
  METHODS
  The patient underwent microvascular decompression surgery. During surgery, it was confirmed that an abnormal loop of the right AICA was compressing the right accessory nerve. Compression was released by the interposition of muscle between the artery and the nerve.
  
  
  CONCLUSIONS
  The patient's postoperative course was uneventful, and his symptoms were fully relieved at the 2-year follow-up examination. This is the first reported case of spasmodic torticollis attributable to compression by the AICA; usually, the blood vessels involved are the vertebral artery and the posteroinferior cerebellar artery.
authors.affiliation: Department of Neurosurgery, University of Messina, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Alafaci
authors.forename: F M
authors.initials: FM
authors.lastname: Salpietro
authors.forename: G
authors.initials: G
authors.lastname: Montemagno
authors.forename: G
authors.initials: G
authors.lastname: Grasso
authors.forename: F
authors.initials: F
authors.lastname: Tomasello
mesh_terms: D020436:Accessory Nerve Diseases / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D000368:Aged; D001158:Arteries / Q000473:pathology / Q000601:surgery; D002531:Cerebellum / Q000098:blood supply*; D019299:Decompression, Surgical; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D006801:Humans; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D008866:Microsurgery; D009408:Nerve Compression Syndromes / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D014103:Torticollis / Q000209:etiology* / Q000601:surgery