Dataset Information

Evaluation of intravoxel incoherent motion fitting methods in low-perfused tissue.

ABSTRACT:

Purpose

To investigate the robustness of constrained and simultaneous intravoxel incoherent motion (IVIM) fitting methods and the estimated IVIM parameters (D, D* and f) for applications in brain and low-perfused tissues.

Materials and methods

Model data simulations relevant to brain and low-perfused tumor tissues were computed to assess the accuracy, relative bias, and reproducibility (CV%) of the fitting methods in estimating the IVIM parameters. The simulations were performed at a series of signal-to-noise ratio (SNR) levels to assess the influence of noise on the fitting.

Results

The estimated IVIM parameters from model simulations were found significantly different (P < 0.05) using simultaneous and constrained fitting methods at low SNR. Higher accuracy and reproducibility were achieved with the constrained fitting method. Using this method, the mean error (%) for the estimated IVIM parameters at a clinically relevant SNR = 40 were D 0.35, D* 41.0 and f 4.55 for the tumor model and D 1.87, D* 2.48, and f 7.49 for the gray matter model. The most robust parameters were the IVIM-D and IVIM-f. The IVIM-D* was increasingly overestimated at low perfusion.

Conclusion

A constrained IVIM fitting method provides more accurate and reproducible IVIM parameters in low-perfused tissue compared with simultaneous fitting.

Level of evidence

3 J. MAGN. RESON. IMAGING 2017;45:1325-1334.

SUBMITTER: Meeus EM

PROVIDER: S-EPMC5412931 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Evaluation of intravoxel incoherent motion fitting methods in low-perfused tissue.

Meeus Emma M EM Novak Jan J Withey Stephanie B SB Zarinabad Niloufar N Dehghani Hamid H Peet Andrew C AC

Journal of magnetic resonance imaging : JMRI 20160822 5

<h4>Purpose</h4>To investigate the robustness of constrained and simultaneous intravoxel incoherent motion (IVIM) fitting methods and the estimated IVIM parameters (D, D* and f) for applications in brain and low-perfused tissues.<h4>Materials and methods</h4>Model data simulations relevant to brain and low-perfused tumor tissues were computed to assess the accuracy, relative bias, and reproducibility (CV%) of the fitting methods in estimating the IVIM parameters. The simulations were performed a ...[more]

PMID: 27545824

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Dataset Information

Evaluation of intravoxel incoherent motion fitting methods in low-perfused tissue.

Purpose

Materials and methods

Results

Conclusion

Level of evidence

Publications

Evaluation of intravoxel incoherent motion fitting methods in low-perfused tissue.

Similar Datasets

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