Basic Science and Pathogenesis.

Area of Science:

• Neuroimaging
• Pathology
• Biomarker Discovery

Background:

• Quantitative susceptibility mapping (QSM) quantifies brain tissue magnetic susceptibility using MRI.
• QSM is a potential marker for blood-brain barrier (BBB) leakage, implicated in cerebral amyloid angiopathy (CAA).
• The prevalence and pathological validation of QSM for BBB leakage in CAA's medial temporal lobe (MTL) are underexplored.

Purpose of the Study:

• To validate QSM as a non-invasive marker of BBB leakage in CAA.
• To investigate the prevalence of BBB leakage in the MTL of CAA cases.
• To perform pathological validation of QSM using advanced imaging and histology.

Main Methods:

• Ultra-high resolution 7 Tesla MRI and QSM calculation on autopsy brain tissue from CAA cases.
• Micro-computer tomography (CT) and 3D histology (H&E, iron, calcium, amyloid-β, fibrin staining) for detailed tissue analysis.
• Alignment of MRI, micro-CT, and histological data; comparison with in vivo MRI (DCE-MRI) data from CAA and control cases.

Main Results:

• Comparison of regional QSM with deep-learning based measures of iron, calcium, and fibrin deposits.
• Single-vessel analysis to correlate perivascular QSM with perivascular fibrin density.
• Comparison of in vivo MTL QSM values with k-trans values from DCE-MRI in CAA and control cohorts.

Conclusions:

• This study aims to validate QSM as a potential non-invasive measure of BBB leakage.
• Findings will contribute to understanding BBB dynamics in CAA.
• The research bridges advanced MRI techniques with detailed histopathological validation.