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Bound pool fractions complement diffusion measures to describe white matter micro and macrostructure.

ABSTRACT: Diffusion imaging and bound pool fraction (BPF) mapping are two quantitative magnetic resonance imaging techniques that measure microstructural features of the white matter of the brain. Diffusion imaging provides a quantitative measure of the diffusivity of water in tissue. BPF mapping is a quantitative magnetization transfer (qMT) technique that estimates the proportion of exchanging protons bound to macromolecules, such as those found in myelin, and is thus a more direct measure of myelin content than diffusion. In this work, we combined BPF estimates of macromolecular content with measurements of diffusivity within human white matter tracts. Within the white matter, the correlation between BPFs and diffusivity measures such as fractional anisotropy and radial diffusivity was modest, suggesting that diffusion tensor imaging and bound pool fractions are complementary techniques. We found that several major tracts have high BPF, suggesting a higher density of myelin in these tracts. We interpret these results in the context of a quantitative tissue model.

SUBMITTER: Stikov N

PROVIDER: S-EPMC2997845 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Bound pool fractions complement diffusion measures to describe white matter micro and macrostructure.

Stikov Nikola N Perry Lee M LM Mezer Aviv A Rykhlevskaia Elena E Wandell Brian A BA Pauly John M JM Dougherty Robert F RF

NeuroImage 20100907 2

Diffusion imaging and bound pool fraction (BPF) mapping are two quantitative magnetic resonance imaging techniques that measure microstructural features of the white matter of the brain. Diffusion imaging provides a quantitative measure of the diffusivity of water in tissue. BPF mapping is a quantitative magnetization transfer (qMT) technique that estimates the proportion of exchanging protons bound to macromolecules, such as those found in myelin, and is thus a more direct measure of myelin con ...[more]

PMID: 20828622

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Bound pool fractions complement diffusion measures to describe white matter micro and macrostructure.

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Bound pool fractions complement diffusion measures to describe white matter micro and macrostructure.

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