MRI assessment of whole-brain structural changes in aging

Area of Science:

• Neuroimaging
• Gerontology
• Radiology

Background:

• Brain aging involves heterogeneous structural changes with clinical implications.
• These changes impact brain health independently and additively.
• Magnetic Resonance Imaging (MRI) visualizes many age-related brain alterations.

Purpose of the Study:

• To validate the MRI-based Brain Atrophy and Lesion Index (BALI) for assessing whole-brain structural changes.
• To evaluate the BALI approach using clinical MRI examinations from diverse cohorts.

Main Methods:

• Utilized data from three independent studies: ADNI Phase II, NACC, and Tianjin Medical University General Hospital.
• Analyzed 3.0-Tesla MRI scans (T1WI, T2WI, T2-FLAIR, T2*GRE) using the BALI rating scheme.
• Included a total of 1842 participants with varying ages and cognitive statuses.

Main Results:

• BALI scores across different MRI sequences demonstrated high correlations (r² > 0.69).
• BALI scores correlated significantly with age (r² > 0.29) and differed by cognitive status (χ² > 26.48).
• T2-FLAIR excelled in detecting white matter lesions, while T2WI identified perivascular spaces, and T2*GRE detected microhemorrhages.

Conclusions:

• T1WI and T2WI-based BALI evaluations reliably identified age and dementia-related structural brain decline.
• Integrating additional MRI sequences improved lesion differentiation.
• Further research aims to develop BALI into a clinical tool for diagnosing and intervening in brain aging.