Implications of Hydrocephalus on FDG-PET Statistical Parametric Mapping Analysis in Neurodegenerative Disease Evaluation

Z score distributions in cingulate regions (ACG, MCG, PCG) and CBL. Boxplots illustrating the z score distributions for the ACG, MCG, PCG, and CBL. The median z scores for the ACG, MCG, and PCG are notably lower than those of the CBL, which serves as the reference region. The CBL shows a narrow distribution centered near zero, confirming its role as a stable control. In contrast, the MCG demonstrates the widest range of z scores with the lowest median value, indicating greater variability in FDG uptake, while the ACG and PCG show intermediate distributions with less variability. The circles outside the boxes for ACG and MCG represent statistical outliers.

MRI findings in a representative subject. A 71-year-old man presenting with cognitive decline and gait impairment underwent MRI as part of his initial work-up. Axial (A and B) and coronal (C) reformats of 3D T1-weighted MPRAGE images are shown, demonstrating characteristic findings of communicating hydrocephalus. A, Crowding of sulci near the vertex. B, Disproportionate enlargement of the lateral ventricles. C, Narrowing of the callosal angle.