To investigate the relationship between hippocampal volume and biomarkers of amyloid-beta (Aβ) pathology in patients with the clinical diagnosis of mild Alzheimer's disease (AD) using voxel-based morphometry (VBM).

In the diagnosis of AD, the position of biomarkers from CSF and amyloid imaging with PET is increasing. However, it is often difficult to predict the presence of Aβ pathology with the clinical diagnosis and conventional imaging study. VBM provides an automated and unbiased assessment of brain atrophy. VBM supporting software, named BAAD (Brain Anatomical Analysis using Diffeomorphic deformation) displays z-scores and volumes of MNI anatomical ROIs.

In the present study, 19 mild AD patients with the results of Aβ biomarkers by CSF study and/or amyloid PET obtained were enrolled. The subjects were divided into two groups based on Aβ biomarkers. Nine patients were Aβ positive and ten patients were negative. BAAD was used to calculate the hippocampal volume and total intracranial volume (TIV). We corrected the hippocampal volume so that the TIV would be constant (1500 mL) to eliminate the influence of individual differences in the brain volume.