IC-P-006: Analysis of regional cerebral volume between normal pressure hydrocephalus and Alzheimer’s disease

Normal pressure hydrocephalus (NPH) is a reversible dementia characterized by gait disturbance, incontinence and dementia. In elderly dementia patients with dilated ventricles, it is often difficult to differentiate NPH from Alzheimer's disease (AD) with visual measurement of MRI. This study investigates the differences of regional cerebral volumes between NPH patients and those with AD to see if regional cerebral atrophy could be used as a distinguishing characteristic of these two disorders. MR images of 9 patients with a clinical diagnosis of NPH who improved after CSF drainage were compared with 10 AD patients and 10 normal control volunteers. Objective, computer–aided volumetric measurement with ANALYER program of the frontal lobes, parietal lobes, occipital lobes, temporal lobes, hippocampi and ventricle were obtained. Volume of each brain regions divided with whole brain volume to correct individual variation of brain volume. NPH patients and those with AD have CDR 0.5 respectively. And their MMSE score was not different statistically. Compared with those for control volunteers, NPH patients showed smaller bilateral frontal, occipital lobe and hippocampal and ventricle volumes (p < 0.05). Compared with those for patients with AD, patients with NPH had significantly smaller bilateral frontal, left occipital lobe and ventricle volumes (p <0.05). Clinical symptoms and signs of NPH that differ from AD may be associated with decreased volumes of bilateral frontal lobes not with hippocampal atrophy. And smaller hippocampal volumes in NPH patients may be due to mechanical compression by increased cerebrospinal fluid. Measurement of regional brain volume provides diagnostic discrimination NPH from AD. This study was supported by a grant of the Korea Health 21 R&D Project, Ministry of Health & Welfare, Republic of Korea (A050079).