Comparison of CSF Distribution between Idiopathic Normal Pressure Hydrocephalus and Alzheimer Disease

Scatterplots and receiver operating characteristic curves for the differential diagnosis of idiopathic normal pressure hydrocephalus and Alzheimer disease. The left upper diagram (A) shows the scatterplot and linear regression for the correlation between the BVR at the anterior level (x-axis) and those at the posterior commissure level (y-axis). The right upper diagram (B) shows the scatterplot of the 3D volumetric convexity subarachnoid space to ventricle ratio-1 (CVR-1) and CVR-2. The purple circle indicates iNPH, the purple triangle indicates iNPH concurrent with Alzheimer disease, the open red triangle indicates AD, and the open red circle indicates control. The lower diagram shows the receiver operating characteristic graph curves of BVR (left, C), CVR-1, and CVR-2 (right, D) for the differential diagnosis of iNPH or iNPH with AD from AD or controls. The x-axis shows specificity, and the y-axis shows sensitivity. The black marks indicate the point of the maximum area under the receiver operating characteristic curve and optimal thresholds (sensitivity and specificity). The maximum areas under the receiver operating characteristic curves for each comparison are displayed in the lower graph.

Mean volumes of the total ventricle and total subarachnoid space. The mean volumes of the total ventricle are displayed in a downward direction (dotted pattern). The mean volumes of the total subarachnoid spaces are displayed after division of the upper (vertical striped pattern) and lower parts (wave pattern) in a horizontal section on the anterior/posterior commissure plane at the level of the junction point of the vein of Galen and straight sinus.