Dataset Information

Toward nonparametric diffusion- T1 characterization of crossing fibers in the human brain.

ABSTRACT:

Purpose

To estimate T1 for each distinct fiber population within voxels containing multiple brain tissue types.

Methods

A diffusion- T1 correlation experiment was carried out in an in vivo human brain using tensor-valued diffusion encoding and multiple repetition times. The acquired data were inverted using a Monte Carlo algorithm that retrieves nonparametric distributions P(D,R1) of diffusion tensors and longitudinal relaxation rates R1=1/T1 . Orientation distribution functions (ODFs) of the highly anisotropic components of P(D,R1) were defined to visualize orientation-specific diffusion-relaxation properties. Finally, Monte Carlo density-peak clustering (MC-DPC) was performed to quantify fiber-specific features and investigate microstructural differences between white matter fiber bundles.

Results

Parameter maps corresponding to P(D,R1) 's statistical descriptors were obtained, exhibiting the expected R1 contrast between brain tissue types. Our ODFs recovered local orientations consistent with the known anatomy and indicated differences in R1 between major crossing fiber bundles. These differences, confirmed by MC-DPC, were in qualitative agreement with previous model-based works but seem biased by the limitations of our current experimental setup.

Conclusions

Our Monte Carlo framework enables the nonparametric estimation of fiber-specific diffusion- T1 features, thereby showing potential for characterizing developmental or pathological changes in T1 within a given fiber bundle, and for investigating interbundle T1 differences.

SUBMITTER: Reymbaut A

PROVIDER: S-EPMC7898694 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Publications

Toward nonparametric diffusion- T1 characterization of crossing fibers in the human brain.

Reymbaut Alexis A Critchley Jeffrey J Durighel Giuliana G Sprenger Tim T Sughrue Michael M Bryskhe Karin K Topgaard Daniel D

Magnetic resonance in medicine 20201210 5

<h4>Purpose</h4>To estimate T1 for each distinct fiber population within voxels containing multiple brain tissue types.<h4>Methods</h4>A diffusion- T1 correlation experiment was carried out in an in vivo human brain using tensor-valued diffusion encoding and multiple repetition times. The acquired data were inverted using a Monte Carlo algorithm that retrieves nonparametric distributions P(D,R1) of diffusion tensors and longitudinal relaxation rates R1=1/T1 . Orientation distribution functions ( ...[more]

PMID: 33301195

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Dataset Information

Toward nonparametric diffusion- T1 characterization of crossing fibers in the human brain.

Purpose

Methods

Results

Conclusions

Publications

Toward nonparametric diffusion- T1 characterization of crossing fibers in the human brain.

Similar Datasets

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