Distortion correction and robust tensor estimation for MR diffusion imaging.
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.
Mangin
J-F
JF
Service Hospitalier Frédéric Joliot, CEA, 91401 Orsay, France. mangin@shfj.cea.fr
Poupon
C
C
Clark
C
C
Le Bihan
D
D
Bloch
I
I
D016477:Artifacts; D001921:Brain / Q000033:anatomy & histology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D015233:Models, Statistical; D011786:Quality Control; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D013269:Stochastic Processes