title: Gravitational shunt complications after a five-year follow-up.
abstract: BACKGROUND
  Gravitational shunts (G-valves) for ventriculo-peritoneal (VP) shunting have been available since 1996. We analyzed shunt complications in patients with a complete minimum follow-up of 5 years.
  
  
  METHODS
  Between 1996 and 2002, we implanted 282 VP G-valves in various forms of adult chronic hydrocephalus, of which 130 provided a complete data set with an annual follow-up. Adjustable and non-adjustable G-valves were used: the Miethke Dual-Switch valve, the Miethke GAV-valve and a combination of adjustable Codman-Hakim valves with the Miethke Shunt-Assistant. In cases of supposed mechanical shunt failure, the explanted shunts were examined in a bench test.
  
  
  RESULTS
  The total complication rate was 21%:3% shunt infections, 3% catheter dislocation/fracture, 5% underdrainage and 9% overdrainage occurred. Half of the overdrainage complications could be managed conservatively. Underdrainage complications resulted from the chosen opening pressure being too high (n = 3), a secondary increase in intraperitoneal pressure (n = 2) or from "real" shunt failure in one case according to bench test results.
  
  
  CONCLUSIONS
  G-valves demonstrate sufficient long-term performance over multiple years, and real shunt-related complications are rare. The frequency of revision due to overdrainage is low (4.5%).
authors.affiliation: Department of Neurosurgery, Saarland University Medical School, Homburg-Saar, Germany. Michael.Kiefer@uks.eu
authors.forename: Michael
authors.initials: M
authors.lastname: Kiefer
authors.forename: Regina
authors.initials: R
authors.lastname: Eymann
mesh_terms: D000328:Adult; D004868:Equipment Failure; D006112:Gravitation; D006801:Humans; D006849:Hydrocephalus / Q000601:surgery; D007239:Infections / Q000209:etiology; D053208:Kaplan-Meier Estimate; D011183:Postoperative Complications / Q000209:etiology* / Q000401:mortality; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D013997:Time Factors; D016896:Treatment Outcome; D017287:Ventriculoperitoneal Shunt / Q000009:adverse effects*