title: Shunt survival rates by using the adjustable differential pressure valve combined with a gravitational unit (proGAV) in pediatric neurosurgery.
abstract: OBJECTIVE
  Overdrainage is a chronic complication in shunted pediatric patients with hydrocephalus. The use of adjustability of differential pressure (DP) valves in combination with antisiphoning devices may help to overcome this sequela and may diminish the rate of possible shunt failures. The purpose of this retrospective study is to report our experience on shunt survival and infection rate with an adjustable DP valve with integrated gravitational unit in pediatric hydrocephalus.
  
  
  METHODS
  The proGAV consists of an adjustable differential pressure (DP) valve and a gravitational unit. During the time period of July 2004 and December 2009, a total of 237 adjustable gravitational valves were used in 203 children (age, 6.5 ± 6.54; 0-27 years). In the follow-up period, valve and shunt failures as well as rate of infection were recorded.
  
  
  RESULTS
  Within the average follow-up time of 21.9 ± 10.3 months (range, 6-72 months), the valve survival rate was 83.8 %. The overall shunt survival rate including all necessary revisions was 64.3 %. Looking at the group of infants (<1 year of age) within the cohort, the valve survival rate was 77.3 % and the shunt survival rate was 60.9 %. The overall infection rate was 4.6 %.
  
  
  CONCLUSIONS
  In a concept of avoiding chronic overdrainage by using the proGAV in hydrocephalic children, we observed a good rate of valve and shunt survival. Compared to previous reported series, we experienced the proGAV as a reliable tool for the treatment of pediatric hydrocephalus.
authors.affiliation: Pediatric Neurosurgery, Charité Universitätsmedizin Berlin, Berlin, Germany. uthomale@charite.de
authors.forename: Ulrich-W
authors.initials: UW
authors.lastname: Thomale
authors.forename: Anna F
authors.initials: AF
authors.lastname: Gebert
authors.forename: Hannes
authors.initials: H
authors.lastname: Haberl
authors.forename: Matthias
authors.initials: M
authors.lastname: Schulz
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002557:Cerebrospinal Fluid Shunts / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004322:Drainage / Q000009:adverse effects* / Q000295:instrumentation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D005500:Follow-Up Studies; D006112:Gravitation; D006801:Humans; D006849:Hydrocephalus / Q000601:surgery*; D057446:Hydrodynamics; D007223:Infant; D007231:Infant, Newborn; D019585:Intracranial Hypotension / Q000209:etiology / Q000517:prevention & control*; D053208:Kaplan-Meier Estimate; D008297:Male; D011312:Pressure; D016896:Treatment Outcome; D055815:Young Adult