Shusuke Moriuchi, Makoto Dehara, Takeshi Shimizu, Shogo Fukuya, Takanori Fukunaga, Yasushi Hagihara and Takao Soda
We often encounter idiopathic normal-pressure hydrocephalus (iNPH) and mild cognitive impairment (MCI) in the
same patient. Four iNPH patients whose gait improved following placement of a lumbar-peritoneal shunt (LPS) and
whose cognitive function improved after administration of donepezil are reported. LPS is useful for improvement of
gait disturbance in iNPH, and donepezil is used to treat impaired memory in dementia of Alzheimer’s type (DAT).
These four patients showed improvements in gait disturbances postoperatively, and just after donepezil
administration, improvements in cognitive symptoms were recognized in the memory tests of the Mini-Mental State
Examination (MMSE). The four patients (two males and two females) ranged in age from 72 to 81 years (mean age:
77 years). In all patients, disproportionately enlarged subarachnoid-space hydrocephalus (DESH) was recognized
on imaging examinations, and improvements after the tap test were considered to be indications for surgery. The
improvements in the Timed Up and Go Test (TUG) were from 25% to 36%. The patients’ mean MMSE score was 27
points preoperatively, 27 points at 1 week after LPS placement, and 30 points at 3 months after LPS placement.
Treatment with donepezil appeared to be effective for residual cognitive impairments after LPS placement.