title: [Method and results of lumbar infusion test in normal pressure hydrocephalus: review of the literature].
abstract: BACKGROUND
  The cerebrospinal (CSF) infusion test is used to analyze the dynamics of CSF circulation. We describe the technique and report test results obtained in subjects with normal pressure hydrocephalus.
  
  
  BACKGROUND
  The CSF infusion test is based on pressure monitoring during a continuous infusion of saline solution into the CSF space via a lumbar puncture. The main parameters are: intracranial pressure, resistance to CSF outflow (Rout), and compliance of the cranial enclosure estimated by the pressure-volume index. Our review of the recent literature dealing with the results of infusion test in normal pressure hydrocephalus indicates that the positive predictive value is about 80 % for Rout greater than 12 mmHg/ml per minute, i.e. shunt response is observed in 80 % of patients. The information available in the literature for assessing negative predictive value of Rout and usefulness of compliance is limited.
  
  
  CONCLUSIONS
  The CSF infusion test may be helpful for the diagnosis of normal pressure hydrocephalus, as supplemental testing when the diagnosis is not certain. We propose a procedure, which includes the infusion test, for identifying shunt-responsive patients.
authors: Service de neurochirurgie, hôpital Dupuytren, CHU, Limoges, France. francois.caire@chu-limoges.fr
authors: F
authors: F
authors: Caire
authors: J-J
authors: JJ
authors: Moreau
mesh_terms: D000465:Algorithms; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000134:cerebrospinal fluid* / Q000175:diagnosis*; D007427:Intracranial Pressure / Q000502:physiology; D008161:Lumbosacral Region; D015233:Models, Statistical; D010477:Perfusion