title: First clinical experiences in patients with idiopathic normal-pressure hydrocephalus with the adjustable gravity valve manufactured by Aesculap (proGAV(Aesculap)).
abstract: OBJECTIVE
  Improved clinical outcomes after implantation of a low pressure valve in patients with idiopathic normal-pressure hydrocephalus is usually achieved at the expense of a higher overdrainage rate. Can an adjustable valve with a gravitational unit provide optimal results?
  
  
  METHODS
  In a prospective clinical outcome study conducted in the Unfallkrankenhaus Berlin, 30 patients with idiopathic normal-pressure hydrocephalus were treated surgically between June 2004 and May 2005 with the valve combination described above, and reexamination 3 months or 6 months postoperatively.
  
  
  RESULTS
  Clinical outcome correlates with opening pressure level of the valve. Controlled adjustment of the valve from 100 mmH2O to 70 mmH2O, and then to 50 mmH2O after 3 months, permits optimum adaptation of the brain to the implanted valve without overdrainage complications.
  
  
  CONCLUSIONS
  Advantages of this programmable gravity valve include: 1) the absence of unintentional readjustment through external magnets, and 2) the possibility of controlling the valve setting using an accessory instrument without the need for x-ray monitoring. A significant disadvantage is adjusting the valve after implantation. From the clinical point of view, this new "proGAV(Aesculap)" valve is a necessary development in the right direction, but at the moment it is still beset with technical problems.
authors: Department of Neurosurgery, Unfallkrankenhaus Berlin, Berlin, Germany. ullrich.meier@ukb.de
authors: U
authors: U
authors: Meier
authors: J
authors: J
authors: Lemcke