Dataset Information

Microstructure Characterization of Bone Metastases from Prostate Cancer with Diffusion MRI: Preliminary Findings.

ABSTRACT:

Purpose

To examine the usefulness of rich diffusion protocols with high b-values and varying diffusion time for probing microstructure in bone metastases. Analysis techniques including biophysical and mathematical models were compared with the clinical apparent diffusion coefficient (ADC).

Methods

Four patients were scanned using 13 b-values up to 3,000 s/mm² and diffusion times ranging 18-52 ms. Data were fitted to mono-exponential ADC, intravoxel incoherent motion (IVIM), Kurtosis and Vascular, extracellular, and restricted diffusion for cytometry in tumors (VERDICT) models. Parameters from the models were compared using correlation plots.

Results

ADC and IVIM did not fit the data well, failing to capture the signal at high b-values. The Kurtosis model best explained the data in many voxels, but in voxels exhibiting a more time-dependent signal, the VERDICT model explained the data best. The ADC correlated significantly (p < 0.004) with the intracellular diffusion coefficient (r = 0.48), intracellular volume fraction (r = -0.21), and perfusion fraction (r = 0.46) parameters from VERDICT, suggesting that these factors all contribute to ADC contrast. The mean kurtosis correlated with the intracellular volume fraction parameter (r = 0.26) from VERDICT, consistent with the hypothesis that kurtosis relates to cellularity, but also correlated weakly with the intracellular diffusion coefficient (r = 0.18) and cell radius (r = 0.16) parameters, suggesting that it may be difficult to attribute physical meaning to kurtosis.

Conclusion

Both Kurtosis and VERDICT explained the diffusion signal better than ADC and IVIM, primarily due to poor fitting at high b-values in the latter two models. The Kurtosis and VERDICT models captured information at high b using parameters (Kurtosis or intracellular volume fraction and radius) that do not have a simple relationship with ADC and that may provide additional microstructural information in bone metastases.

SUBMITTER: Bailey C

PROVIDER: S-EPMC5820304 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Microstructure Characterization of Bone Metastases from Prostate Cancer with Diffusion MRI: Preliminary Findings.

Bailey Colleen C Collins David J DJ Tunariu Nina N Orton Matthew R MR Morgan Veronica A VA Feiweier Thorsten T Hawkes David J DJ Leach Martin O MO Alexander Daniel C DC Panagiotaki Eleftheria E

Frontiers in oncology 20180216

<h4>Purpose</h4>To examine the usefulness of rich diffusion protocols with high <i>b</i>-values and varying diffusion time for probing microstructure in bone metastases. Analysis techniques including biophysical and mathematical models were compared with the clinical apparent diffusion coefficient (ADC).<h4>Methods</h4>Four patients were scanned using 13 <i>b</i>-values up to 3,000 s/mm<sup>2</sup> and diffusion times ranging 18-52 ms. Data were fitted to mono-exponential ADC, intravoxel incoher ...[more]

PMID: 29503808

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Dataset Information

Microstructure Characterization of Bone Metastases from Prostate Cancer with Diffusion MRI: Preliminary Findings.

Purpose

Methods

Results

Conclusion

Publications

Microstructure Characterization of Bone Metastases from Prostate Cancer with Diffusion MRI: Preliminary Findings.

Similar Datasets

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