Distributional Characterization of ICV-Normalized Regional Brain Volumes in Alzheimer’s Disease

Introduction

Alzheimer’s disease (AD) has progressive structural brain changes that can be described using magnetic resonance imaging (MRI). Previous work has used several statistical approaches to compare the volume of brain regions such as the hippocampus, entorhinal cortex, and amygdala. However, many of these approaches assume a Normal or symmetric distribution of regional volumes, which may not fully capture the variance and regional morphological variability of observed brain volumes. This study compares different probability distributions to assess the distributional flexibility needed to characterize brain volumes normalized to intracranial volume (ICV).