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Abstract #4161

Eddy Currents in MT Asymmetry Imaging with Alternate Ascending/Descending Directional Navigation (ALADDIN)

Sung-Hong Park1, Tiejun Zhao2, Jung-Hwan Kim1, Fernando E. Boada1, 3, Kyongtae Ty Bae1

1Radiology, University of Pittsburgh, Pittsburgh, PA, United States; 2MR Research Support, Siemens Healthcare, Pittsburgh, PA, United States; 3Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States

ALADDIN is a new imaging technique that provides interslice perfusion-weighted and MT asymmetry images. We investigated the effects of gradient imperfections on ALADDIN MT asymmetry imaging in this study. Subtraction artifacts were detectable in ALADDIN MT asymmetry images from an agarose phantom but not from a water phantom, in agreement with the theoretical analysis that they were induced by mismatch in MT frequencies associated with readout eddy currents. The artifacts were suppressed by averaging signals over the readout gradient polarities independent of scan parameters. With suppression of the artifacts, ALADDIN signals of human brain were less dependent on scan conditions.

Keywords

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