Toward more robust and reproducible diffusion kurtosis imaging.
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ABSTRACT: Purpose
The general utility of diffusion kurtosis imaging (DKI) is challenged by its poor robustness to imaging artifacts and thermal noise that often lead to implausible kurtosis values.Theory and methods
A robust scalar kurtosis index can be estimated from powder-averaged diffusion-weighted data. We introduce a novel DKI estimator that uses this scalar kurtosis index as a proxy for the mean kurtosis to regularize the fit.Results
The regularized DKI estimator improves the robustness and reproducibility of the kurtosis metrics and results in parameter maps with enhanced quality and contrast.Conclusion
Our novel DKI estimator promotes the wider use of DKI in clinical research and potentially diagnostics by improving the reproducibility and precision of DKI fitting and, as such, enabling enhanced visual, quantitative, and statistical analyses of DKI parameters.
SUBMITTER: Henriques RN
PROVIDER: S-EPMC8199974 | biostudies-literature | 2021 Sep
REPOSITORIES: biostudies-literature
Publications
Toward more robust and reproducible diffusion kurtosis imaging.
Henriques Rafael N RN Jespersen Sune N SN Jones Derek K DK Veraart Jelle J
Magnetic resonance in medicine 20210408 3
<h4>Purpose</h4>The general utility of diffusion kurtosis imaging (DKI) is challenged by its poor robustness to imaging artifacts and thermal noise that often lead to implausible kurtosis values.<h4>Theory and methods</h4>A robust scalar kurtosis index can be estimated from powder-averaged diffusion-weighted data. We introduce a novel DKI estimator that uses this scalar kurtosis index as a proxy for the mean kurtosis to regularize the fit.<h4>Results</h4>The regularized DKI estimator improves th ...[more]
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