title: Management of hydrocephalus in infants by using shunts with adjustable valves.
abstract: OBJECTIVE
  Previous reports suggest that the use of adjustable differential-pressure valves may improve shunt performance. The absence of a flow- or siphon-controlled mechanism, however, is a concern. The goal of this prospective study was to assess the efficacy of valve adjustments in preventing slitlike ventricles in children < 6 months old after the first shunt insertion.
  
  
  METHODS
  A total of 15 infants < 6 months of age who were undergoing initial shunt placement were included. Imaging was performed preoperatively, at 14 days postoperatively, and every 4 weeks thereafter. Ventricle size was assessed using ultrasonography and MR imaging or cerebral CT scanning at 1 and 2 years postoperatively. Clinical follow-up duration was 24 months for all patients. Valve settings were changed by 50 mm H(2)O if ventricle size decreased by 30% compared to preoperative size.
  
  
  RESULTS
  The valve pressure setting was increased to 200 mm H(2)O in 11 children within the follow-up time, whereas ventricle size decreased from 0.6 +/- 0.08 to 0.39 +/- 0.09 (frontal/occipital horn ratio, mean +/- standard deviation). There was neither clinical nor radiological evidence of underdrainage.
  
  
  CONCLUSIONS
  The adjustable differential-pressure valve used in this study was not effective in preventing slitlike ventricles in the majority of patients. Despite the small number of patients, this study provides a rationale for examining whether new shunt designs (gravitational shunt valves) are superior to conventional shunt systems in managing challenging hydrocephalus problems.
authors.affiliation: Department of Neurosurgery, University Hospital RWTH, Aachen, Germany. mweinzierl@ukaachen.de
authors.forename: Martin R
authors.initials: MR
authors.lastname: Weinzierl
authors.forename: Veit
authors.initials: V
authors.lastname: Rohde
authors.forename: Joachim M
authors.initials: JM
authors.lastname: Gilsbach
authors.forename: Marcus
authors.initials: M
authors.lastname: Korinth
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging; D002557:Cerebrospinal Fluid Shunts / Q000295:instrumentation*; D005500:Follow-Up Studies; D006801:Humans; D006849:Hydrocephalus / Q000601:surgery*; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D011446:Prospective Studies; D011474:Prosthesis Design; D014057:Tomography, X-Ray Computed