Methodological considerations for measuring rates of brain atrophy

Area of Science:

• Neuroimaging
• Biomarker Development
• Neurodegenerative Diseases

Background:

• Serial magnetic resonance imaging (MRI) is crucial for tracking brain atrophy.
• Accurate measurement of atrophy rates is essential for understanding neurodegenerative disease progression.

Purpose of the Study:

• To systematically compare techniques for measuring brain atrophy rates using serial MRI.
• To identify optimal methods for detecting differences between cognitively normal elderly subjects and Alzheimer's disease (AD) patients.

Main Methods:

• Evaluated different volume change computation methods and image preprocessing steps (intensity normalization, alignment, bias field correction).
• Assessed the impact of MRI hardware changes and manual volume editing variations.
• Calculated whole-brain and ventricular atrophy rates for comparison.

Main Results:

• Ventricular atrophy measures generally showed greater separation between clinical groups than whole-brain measures.
• Bias field correction and major MRI hardware changes did not significantly affect group separation.
• The chosen method demonstrated high precision and captured expected AD-related biological changes.

Conclusions:

• Serial MRI-based atrophy rate measurements are viable surrogate markers for AD and other dementing disorders.
• The optimized method offers excellent precision and biological relevance for biomarker applications.
• This technique holds promise for monitoring disease progression in neurodegenerative conditions.