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Abstract #2481

Comparisons of Quantitative Susceptibility Mapping (QSM) by Using Restricted Oversampled Spatial Unit Dipole Field

Mai Murashima1, Tomohiro Ueno1, Naozo Sugimoto1

1Human Health Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan

In Quantitative susceptibility mapping (QSM), measured magnetic field distributions have to be deconvolved with a dipole field. The dipole field is effective even in a long range, and a rapidly changing function of a position in a short range. In order to access these problems, we performed numerical simulations taking into account partial volume effects in QSM by using the dipole fields with various field sizes and oversampling factors. We found that the diameter 21voxels was enough for the field size, and that the oversampled dipole field of factor 3 was sufficient for observing effects on the susceptibility estimation.

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Keywords

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