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Abstract #4263

Double-Angle Amide Proton Transfer Imaging: A New Chemical Exchange Saturation Transfer (CEST) Contrast

Zhongliang Zu1, 2, Vaibhav Janve1, 3, Junzhong Xu1, 2, Mark D. Does1, 2, John Gore1, 2, Daniel Gochberg1, 2

1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States; 2Department of Radiology, Vanderbilt University, Nashville, TN, United States; 3Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, United States

APT imaging has shown promise in many clinical applications. However, the conventional CEST asymmetry analysis, by subtracting a label scan from a reference scan, is sensitive to confounding contributions from magnetic field inhomogeneities, inherently asymmetric macromolecular resonances, and lipid. In this study, we introduce a new CEST contrast that avoids these issues by creating label and reference scans based on varying the irradiation pulse turn angle (180 and 360 degree) instead of the frequency offset (3.5 and -3.5 ppm). Clear peak has been found at 3.5 ppm by using our method, but not by using the conventional asymmetry analysis.

Keywords

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