Surgical Outcome of Idiopathic Normal Pressure Hydrocephalus according to the Shunt Devices

Kim, Myoung Hoon; Nam, Do Hyun; Na, Duk Ryul; Lee, Jung Il; Kim, Jong Soo; Hong, Seung Chyul; Shin, Hyung Jin; park, Kwan; Eoh, Whan; Kim, Jong Hyun

Abstract

OBJECTIVE
To determine the effect of shunt devices on the surgical outcome in the idiopathic normal pressure hydrocephalus(NPH), the authors present a retrospective analysis of 39 elderly patients who underwent shunt operations between November 1994 and May 2000, retrospectively.
METHODS
The patients enrolled in this study did not have the history of intracranial hemorrhage, head injury, infection, cerebral infarction and brain tumor. The mean age was 69.9(range:52-89) years. Thirteen patients who received operations with simple pressure-control shunt valves(Group I), 22 patients with siphon-control shunt valves(Group II), and four patients with flow-regulating shunt valves (Group III). Final outcome with the clinical improvement and shunt associated complications were evaluated at the last follow-up and the mean follow-up period was 14.7 months.
RESULTS
Signs or symptoms of shunt dysfunction were found in eight of 39 patients(20.5%) in the subsequent course. In group I, five out of 13 patients had suffered from symptomatic subdural hematomas and one from overdrainage symptoms(46.2%);in group II, two out of 22 from underdrainage(9%);in group III, one out of four from symptomatic subdural hematomas(25%). Five patients required operative shunt revisions and five underwent burr-hole trephinations for subdural hematomas. Clinical improvements were observed in 10(79.6%), 19(86.4%), and 3(75%) patients in group I, II, and III respectively. Surgical outcomes were better for patients with siphon-control shunt valves than there with the other shunt valves in terms of shunt associated complications and functional improvements(p=0.05).
CONCLUSION
The shunt operation with siphon-control shunt valves might be good for the elderly patients with idiopathic NPH.