The outcomes of serial cerebrospinal fluid removal in elderly patients with idiopathic normal pressure hydrocephalus

Purpose: Elderly patients with iNPH (idiopathic normal pressure hydrocephalus) might be potentially high-risk surgical patients. Our purpose was to investigate the outcome of serial removal of cerebrospinal fluid (CSF) in the patients with iNPH who refused to have the ventriculoperitoneal or lumboperitoneal shunt surgery or had contraindications to them. Patients and methods: There were 42 patients, with a median age of 78 years. Recurrent CSF removal was performed when the patients had deteriorated gait which was defined as >10% pre-removal change on the average of two walking trials during timed up and go (TUG). All the patients underwent mini-mental status examination (MMSE), frontal assessment battery (FAB), Stroop test, Tinetti Performance Oriented Mobility Assessment (POMA), TUG and nine-hole peg test (NHPT) with the dominant hand, before and after CSF removal. Results: Thirty-five patients had two CSF removal procedures with a mean interim period of 7.4 months ranging from 1.5 to 35 months. Thirteen patients had three CSF removal procedures. The mean TUG scores were decreased after the first, second and third procedures (p<0.001; p<0.001; p=0.007; respectively). The POMA scores including both gait and balance components improved after the first and second procedures (p<0.05; for each). After the third procedure, the increase in POMA-balance score was statistically significant (p<0.05). After the first procedure, the FAB scores and NHPT scores were significantly improved (p<0.02). The median follow-up duration of the patients was 34.5 months. Conclusion: The deterioration of gait disturbance may be improved, and cognitive decline may be stabilized, at least postponed, by applying recurrent CSF removal in those unshunted patients with iNPH.