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PubMed · 12270226

Distortion correction and robust tensor estimation for MR diffusion imaging.

J-F Mangin·C Poupon·C Clark·D Le Bihan·I Bloch
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Abstract

This paper presents a new procedure to estimate the diffusion tensor from a sequence of diffusion-weighted images. The first step of this procedure consists of the correction of the distortions usually induced by eddy-current related to the large diffusion-sensitizing gradients. This correction algorithm relies on the maximization of mutual information to estimate the three parameters of a geometric distortion model inferred from the acquisition principle. The second step of the procedure amounts to replacing the standard least squares-based approach by the Geman-McLure M-estimator, in order to reduce outlier-related artefacts. Several experiments prove that the whole procedure highly improves the quality of the final diffusion maps.

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ArtifactsBrainDiffusion Magnetic Resonance ImagingHumansImage EnhancementModels, StatisticalQuality ControlReproducibility of ResultsSensitivity and SpecificityStatistics as TopicStochastic ProcessesComparative StudyEvaluation StudyJournal Article

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J-F Mangin, C Poupon, C Clark, D Le Bihan, I Bloch. 2002. Distortion correction and robust tensor estimation for MR diffusion imaging.. https://doi.org/10.1016/s1361-8415(02)00079-8

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