Brain structural indicators of β-amyloid neuropathology

Area of Science:

• Neuroimaging
• Neuropathology
• Alzheimer's Disease Research

Background:

• Current methods for detecting early Alzheimer's disease (AD) neuropathology, like cerebrospinal fluid analysis and PET scans, are invasive and costly.
• There is a need for accessible, non-invasive biomarkers to identify preclinical AD.
• Structural MRI offers potential for detailed brain analysis.

Purpose of the Study:

• To develop and validate the multiscale structural mapping (MSSM) procedure for detecting β-amyloid neuropathology in preclinical AD.
• To assess MSSM's ability to capture macrostructural and microstructural brain properties.
• To compare MSSM's efficacy against traditional markers like cortical thickness and hippocampal volume.

Main Methods:

• Utilized structural MRI to apply an improved multiscale structural mapping (MSSM) procedure.
• Analyzed preclinical AD cases (N=220) with confirmed amyloid positivity and negativity.
• Correlated MSSM signal alterations with amyloid PET imaging results.

Main Results:

• MSSM signal alterations were detected in preclinical AD cases, even when cortical thickness and hippocampal volume did not show significant changes.
• Widespread effects of amyloid positivity were observed across the posterior temporal, parietal, and medial prefrontal cortex.
• The MSSM signal showed significant correlation with amyloid PET in nearly half of the cortex, mapping amyloid deposition patterns.

Conclusions:

• The enhanced MSSM procedure using structural MRI can identify regional β-amyloid neuropathology in preclinical AD.
• MSSM provides a non-invasive, regional brain map of amyloid pathology, complementing systemic markers.
• This technique offers a promising, accessible tool for early AD detection and monitoring.