title: Shunt malfunction caused by mischievous twisting of the valve by the patient: case report.
abstract: OBJECTIVE
  We report an instructive case of repetitive shunt obstruction caused by mischievous turning of the valve by the patient.
  
  
  METHODS
  A 7-year-old boy underwent shunt replacement for hydrocephalus caused by intraventricular hemorrhage at birth; the shunt had been revised a month earlier. The boy experienced occasional episodes of headache and vomiting after the revision. A shunt survey revealed a twisted tube just proximal to the valve.
  
  
  METHODS
  After the valve was returned to its original position, the symptoms resolved. The patient confessed to a recent habit of turning the valve.
  
  
  CONCLUSIONS
  Although turning of the valve may be a potential cause of shunt obstruction, the use of craniography and/or a shunt series should be able to reveal these changes.
authors.affiliation: Department of Neurosurgery, Hiroshima City Asa Hospital, Hiroshima, Japan. noge@asa-hosp.city.hiroshima.jp
authors.forename: Shinya
authors.initials: S
authors.lastname: Nabika
authors.forename: Shuichi
authors.initials: S
authors.lastname: Oki
authors.forename: Masayuki
authors.initials: M
authors.lastname: Sumida
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Isobe
mesh_terms: D002557:Cerebrospinal Fluid Shunts; D002648:Child; D004868:Equipment Failure; D006184:Habits; D006801:Humans; D006849:Hydrocephalus / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D011859:Radiography; D012086:Reoperation