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Abstract #2725

New Insights Into PET Count Rate Reduction During Simultaneous MR-PET Measurements

Daniel Brenner1, Christoph Weirich1, Jrgen Scheins1, Etienne Besancon1, Lutz Tellmann1, Hans Herzog1, N. Jon Shah1, 2

1Institute of Neuroscience and Medicine - 4, Forschungszentrum Jlich, Jlich, Germany; 2JARA - Faculty of Medicine, RWTH Aachen University, Aachen, Germany

Minor influences of MRI on the PET detectors during simultaneous MR-PET measurements with the 3T MR-BrainPET have been observed and shown to result in a drop of the measured count rate of up to three percent. This study analyses the distortions generated in the output signal of the PET detector by the time varying MR gradients. Pronounced effects are visible at start and beginning of the gradient ramps while an increased noise level was observed during the gradient flat top.

Keywords

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