title: Pediatric shunt malfunction without ventricular dilatation.
abstract: OBJECTIVE
  Symptomatic ventriculoperitoneal shunt (VPS) malfunction can occur without progressive ventricular dilatation on imaging studies. A review of VPS revisions performed during an 18-month period was conducted to better characterize this cohort. The incidence of VPS malfunction without ventricular dilatation and the clinical features that may predispose to its occurrence have not been previously described.
  
  
  METHODS
  A retrospective review was conducted of all patients under the age of 18 who underwent VPS revision due to shunt malfunction from June 2001 to December 2002. The incidence of various factors that might correlate with the development of low compliance ventricles was examined.
  
  
  RESULTS
  One hundred and seventy-seven patients underwent a total of 287 VPS revisions during the study period; 16 patients (9%) had signs of raised intracranial pressure and showed no radiographic evidence of progressive ventricular dilatation. History of prior shunt-related ventriculitis positively correlated with the development of low compliance ventricles (Fisher's exact test, p = 0.043).
  
  
  CONCLUSIONS
  Nine percent of pediatric patients with symptomatic VPS malfunctions lack radiographic evidence of progressive ventricular dilatation on imaging studies. Patients with prior shunt infections are particularly at risk, necessitating increased vigilance when clinical signs and symptoms are apparent.
authors.affiliation: Division of Neurosurgery, Childrens Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, CA, USA. mcnatt.sean@tchden.org
authors.forename: Sean A
authors.initials: SA
authors.lastname: McNatt
authors.forename: Anthony
authors.initials: A
authors.lastname: Kim
authors.forename: David
authors.initials: D
authors.lastname: Hohuan
authors.forename: Mark
authors.initials: M
authors.lastname: Krieger
authors.forename: J Gordon
authors.initials: JG
authors.lastname: McComb
mesh_terms: D000293:Adolescent; D002552:Cerebral Ventricles / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004868:Equipment Failure; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies; D017287:Ventriculoperitoneal Shunt / Q000295:instrumentation*