title: Hemifacial spasm caused by a hemangioma at the geniculate ganglion: case report.
abstract: OBJECTIVE
  Hemifacial spasm is rarely caused by facial nerve lesions in the temporal bone. Intratemporal facial nerve hemangiomas may initially present as facial spasm.
  
  
  METHODS
  A 30-year-old woman developed right hemifacial spasm. Physicians observed slight weakness on the right side of her face, in addition to the hemifacial spasm, but routine radiological examinations did not detect any abnormal findings along the course of the facial nerve. Although the patient underwent neurovascular decompression, the spasm persisted postoperatively. Two years after surgery, the right facial palsy progressed. Concurrently, the hemifacial spasm diminished. High-resolution computed tomography demonstrated a small mass lesion expanding the cortex of the right petrosal bone involving the geniculate ganglion of the facial nerve.
  
  
  METHODS
  The patient underwent a second craniotomy through a subtemporal extradural route, and the tumor was completely removed. A pathological examination demonstrated a cavernous hemangioma.
  
  
  CONCLUSIONS
  Routine radiological examinations may fail to detect small intratemporal facial nerve hemangiomas, particularly at the geniculate ganglion. Therefore, when physicians encounter atypical facial spasm, the intratemporal portion of the facial nerve should be carefully examined using high-resolution computed tomography.
authors.affiliation: Department of Neurosurgery, University of Hokkaido, School of Medicine, Sapporo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Asaoka
authors.forename: Y
authors.initials: Y
authors.lastname: Sawamura
authors.forename: M
authors.initials: M
authors.lastname: Tada
authors.forename: H
authors.initials: H
authors.lastname: Abe
mesh_terms: D000328:Adult; D003390:Cranial Nerve Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D003399:Craniotomy; D005154:Facial Nerve; D005260:Female; D006392:Hemangioma, Cavernous / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D019569:Hemifacial Spasm / Q000209:etiology*; D006801:Humans; D014057:Tomography, X-Ray Computed