Accurate Susceptibility Quantification from MR Phase Data through the Least Squares Fit Method: Phantom Validation
نویسندگان
چکیده
Introduction: Quantifying magnetic susceptibility of biological tissue using MRI has important clinical implications such as quantifying iron deposition in liver and sub-cortical structures, measuring oxygen saturation in blood, differentiating a hemorrhagic lesion as acute or chronic and identifying calcifications etc.. MR susceptometry of substances taken in standard sphere or cylinder geometries has been done in the past [1,2] through a straight forward field fitting approach. Previously we had evaluated a 3D least-squares algorithm for susceptibility quantification of a single arbitrarily shaped object [4]. This algorithm was based on the Fourier based method for calculating field perturbation from an arbitrary susceptibility distribution. Here we extend this quantification work to a multiple susceptibility-component model. In addition, we apply the method here on a very small object occupying only a few pixels to understand the affect of discretization.
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