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Abstract #4194

Spillover Correction for Quantification of Pulsed-CEST Experiments

Moritz Zaiss1, Olga Ivchenko1, Peter Bachert1

1Dpt. of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Baden-Wrttemberg, Germany

Chemical exchange saturation transfer (CEST) effect of endogenous CEST agents with small frequency offset from water resonance like amide protons (APT) are always diluted by direct saturation of water protons (spillover effect). An analytical spillover correction is presented which allows reconstructing the unperturbed pulsed-proton transfer rate for different flip angles and B1 using only label and reference scan. Additionally, the artificial pulsed-proton transfer rate is shown to be correlated with the analytical cw proton transfer rate. Therefore, the spillover correction provides analytic quantification of pulsed saturation transfer experiments which are feasible in clinical scanners.

Keywords

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