title: Overcoming CSF overdrainage with the adjustable gravitational valve proSA.
abstract: BACKGROUND
  Despite progress in shunt valve technology, CSF overdrainage is still one of the most frequent complications in shunt-treated hydrocephalus. Particularly with regard to young and adolescent patients, treatment of manifest overdrainage is complicated by several hardly influenceable factors such as increasing height and mobility. Therefore, the aim of this study was to evaluate the therapeutic efficiency of the new adjustable gravitational valve, proSA.
  
  
  METHODS
  Sixty-four shunt-treated young hydrocephalus patients aged 1.8-41.4 years (15.5 ± 10.5 years) suffering from clinical and/or radiological overdrainage underwent shunt revision surgery with the implantation of the new proSA valve. Clinical outcome after a 1-year follow-up period, pumping function of the valve chambers as well as the number of necessary postoperative valve adjustments were examined.
  
  
  RESULTS
  Fifty-five patients completed the study as planned. All reported a significant improvement of their clinical condition; 91 % described a complete resolution in symptoms related to overdrainage. Preoperatively, more than 85 % of the valve chambers showed no or very slow refilling with CSF. After a year of proSA treatment, more than 90 % exhibited a normal valve chamber function. During the follow-up period, a total of 136 valve adjustments were necessary. None of the proSA valves had to be surgically revised.
  
  
  CONCLUSIONS
  The postoperative adjustability of the opening pressure level is the advantage of the new gravitational valve. The good clinical outcome is attributed to the new valve technology. The proSA appears to be a promising shunt valve to overcome overdrainage in adolescent and adult hydrocephalus patients.
authors.affiliation: Department of Neurosurgery, Saarland University Medical Center and Saarland University Faculty of Medicine, Homburg/Saar, Germany, christoph.tschan@uks.eu.
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Tschan
authors.forename: Sebastian
authors.initials: S
authors.lastname: Antes
authors.forename: Alexandra
authors.initials: A
authors.lastname: Huthmann
authors.forename: Sonja
authors.initials: S
authors.lastname: Vulcu
authors.forename: Joachim
authors.initials: J
authors.lastname: Oertel
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wagner
mesh_terms: D000293:Adolescent; D000328:Adult; D065634:Cerebrospinal Fluid Leak / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006112:Gravitation; D006801:Humans; D006849:Hydrocephalus / Q000601:surgery*; D015994:Incidence; D007223:Infant; D008297:Male; D011312:Pressure; D012086:Reoperation; D012189:Retrospective Studies; D016896:Treatment Outcome; D017287:Ventriculoperitoneal Shunt / Q000295:instrumentation* / Q000379:methods*; D055815:Young Adult