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Abstract #4193

Nonlinear Estimation of Cylindrically Symmetric Magnetic Susceptibility Anisotropy in Image Space Without a Rigid DTI Prior

Cynthia Wisnieff1, Pascal Spincemaille2, Yi Wang1

1Cornell Univerisity, New York, United States; 2Weill Cornell Medical College, New York, United States

In this work we explore methods of estimating magnetic susceptibility anisotropy, MSA, of the human brain in vivo in image space using only a shape constraint on the susceptibility tensor without imposing prior information on the fiber orientation. Estimation of cylindrically symmetric tensor anisotropy is explored in a carbon fiber phantom and human in vivo data. It was found that anisotropy estimation was similar with some sensitivity to noise in the nonlinear method compared to previously explored k-space MSA estimation methods.

Keywords

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