title: Resolution of trigeminal neuralgia following third ventriculostomy for hydrocephalus associated with Chiari I malformation: case report.
abstract: OBJECTIVE
  Cranial nerve dysfunction, including trigeminal neuralgia, has been associated with Chiari I malformations. In such cases, trigeminal neuralgia is thought to be related to tonsillar compression of the brainstem or to traction on the cranial nerves. Hydrocephalus may be a contributing factor.
  
  
  METHODS
  A 38-year-old woman had right-sided lancinating facial pain typical of trigeminal neuralgia but was otherwise neurologically intact. Magnetic resonance imaging showed no evidence of a compressing vessel. Moderate hydrocephalus and a Chiari I malformation were noted incidentally. The visibility of the aqueduct was poor.
  
  
  METHODS
  The patient underwent a third ventriculostomy and her symptoms resolved completely.
  
  
  CONCLUSIONS
  This is the first case in which trigeminal neuralgia was treated with a third ventriculostomy and one of only four cases of isolated trigeminal neuralgia associated with a Chiari malformation. Acquired aqueductal stenosis may have caused the hydrocephalus which, in turn, caused the Chiari malformation configuration that caused the trigeminal neuralgia. The rationale for the treatment modality and possible causes of Chiari I-induced trigeminal neuralgia are discussed.
authors.affiliation: Centre for Minimally Invasive Neurosurgery, Prince of Wales Private Hospital, Sydney, Australia.
authors.forename: C
authors.initials: C
authors.lastname: Teo
authors.forename: P
authors.initials: P
authors.lastname: Nakaji
authors.forename: D
authors.initials: D
authors.lastname: Serisier
authors.forename: M
authors.initials: M
authors.lastname: Coughlan
mesh_terms: D000328:Adult; D001139:Arnold-Chiari Malformation / Q000150:complications* / Q000175:diagnosis / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000150:complications / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D019635:Neurosurgical Procedures / Q000379:methods; D014277:Trigeminal Neuralgia / Q000175:diagnosis / Q000209:etiology / Q000473:pathology / Q000601:surgery*; D014696:Ventriculostomy / Q000379:methods*