[The importance of hydrostatic valves in the treatment of adult chronic hydrocephalus].

BACKGROUND AND OBJECTIVE

Earlier designs of hydrocephalus valves, focusing on a reduction of the problem of overdrainage, were proved to be insufficiently. Since the middle of the 90's hydrostatic valve, constructions are available, which should solve this problem. The objective of the study was to evaluate, whether these gravitational shunts would indeed reduce the percentage of overdrainage in shunted patients.

METHODS

In 51 patients clinical evaluation and MRI was performed pre- and in regular intervals postoperatively. 21 received a Dual-Switch valve, 14 a programmable Codman Hakim plus Shuntassistent and 6 a combination of a conventional valve with Shuntassistent.

RESULTS

Over 90% of the patients had clear and persisting (over 24 months) clinical benefit from shunting. Only one suffered for some days after shunt implantation from headache in the upright position. No other clinical or imaging hints were given on an overdrainage. The ventricular size was unchanged in patients with a normal pressure hydrocephalus after shunting. In patients with occlusive hydrocephalus only a few showed a significant reduction of the ventricular wide.

CONCLUSION

Gravitational shunts seem to decrease the overdrainage linked to the treatment of chronic hydrocephalus in shunted patients, therefore its use should be standardised when treatment chronic hydrocephalus.