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Abstract #2072

Whole-Brain Assessment of Microscopic Anisotropy Using Multiple Pulse-Field Gradient (MPFG) Diffusion MRI

Alexandru V. Avram1, Joelle E. Sarlls2, Peter J. Basser1

1Section on Tissue Biophysics and Biomimetics, NICHD, National Institutes of Health, Bethesda, MD, United States; 2National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States

Recent studies have shown that multiple pulsed-field gradient (mPFG) diffusion MRI has the potential to exclusively characterize water trapped in microscopic compartments with unique measures of average cell geometry. We applied quadruple PFG diffusion MRI on a clinical scanner to assess microstructural anisotropy parameters across the whole brain. Calculated maps of average axon diameter, axonal water diffusivity, intra-axonal signal fraction, and extracellular water diffusivity provide information that is complementary to that obtained with conventional diffusion tensor imaging (DTI). Upon further improvements in acquisition strategy and tissue modeling, mPFG diffusion MRI could provide a non-invasive whole brain histological assessment.

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Keywords

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