title: A randomised trial of high and low pressure level settings on an adjustable ventriculoperitoneal shunt valve for idiopathic normal pressure hydrocephalus: results of the Dutch evaluation programme Strata shunt (DEPSS) trial.
abstract: BACKGROUND
  In treating idiopathic normal pressure hydrocephalus (INPH) with a shunt there is always a risk of underdrainage or overdrainage. The hypothesis is tested whether patients treated using an adjustable valve preset at the highest opening pressure leads to comparable good clinical results with less subdural effusions than in a control group with an opening pressure preset at a low pressure level.
  
  
  METHODS
  A multicentre prospective randomised trial was performed on a total of 58 patients suspected of INPH. Thirty patients were assigned to (control) group 1 and received a Strata shunt (Medtronic, Goleta, USA) with the valve preset at a performance level (PL) of 1.0, while 28 patients were assigned to group 2 and received a Strata shunt with the valve preset at PL 2.5. In this group the PL was allowed to be lowered until improvement or radiological signs of overdrainage were met.
  
  
  RESULTS
  Significantly more subdural effusions were observed in the improved patients of group 1. There was no statistically significant difference in improvement between both groups overall.
  
  
  CONCLUSIONS
  On the basis of this multicentre prospective randomised trial it is to be recommended to treat patients with INPH with a shunt with an adjustable valve, preset at the highest opening pressure and lowered until clinical improvement or radiological signs of overdrainage occur although slower improvement and more shunt adjustments might be the consequence.
authors: Department of Neurosurgery, Erasmus University Medical Centre, 's Gravendijkwal 230, Rotterdam 3000 CA, The Netherlands. e.j.delwel@erasmusmc.nl
authors: Ernst J
authors: EJ
authors: Delwel
authors: Dirk A
authors: DA
authors: de Jong
authors: Ruben
authors: R
authors: Dammers
authors: Erkan
authors: E
authors: Kurt
authors: Wimar
authors: W
authors: van den Brink
authors: Clemens M F
authors: CM
authors: Dirven
mesh_terms: D003627:Data Interpretation, Statistical; D004867:Equipment Design; D004868:Equipment Failure; D005500:Follow-Up Studies; D020233:Gait Disorders, Neurologic / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000628:therapy*; D009422:Nervous System Diseases / Q000453:epidemiology / Q000209:etiology; D009426:Netherlands; D011312:Pressure; D011446:Prospective Studies; D013353:Subdural Effusion / Q000453:epidemiology / Q000209:etiology; D016896:Treatment Outcome; D017287:Ventriculoperitoneal Shunt / Q000295:instrumentation*
keywords: Csf Dynamics; Dementia; Gait; Geriatrics; Neurosurgery