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Abstract #2594

Interferometric Bloch-Siegert B1+ Mapping at 7T

Patrik Wyss1, Shaihan J. Malik2, Vincent Oltman Boer3, Johanna J. Bluemink3, Alexander Raaijmakers3, Mustafa Cavusoglu4, Peter R. Luijten3, Johannes J. Hoogduin3, Giel Mens5, Anke Henning, 16

1Institute for Biomedical Engineering, UZH and ETH Zurich, Zurich, Switzerland; 2Imaging Sciences and Biomedical Engineering, Kings College London, London, United Kingdom; 3University Medical Center Utrecht, Utrecht, Netherlands; 4Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland; 5Philips Healthcare, Best, Netherlands; 6Max Planck Institute for Biological Cybernetics, Tbingen, Germany

To achieve a sufficient dynamic range for single channel B1+ mapping required for calibration of multi-channel transmit arrays two distinct solutions have been suggestion recently: (1) Bloch-Siegert effect based B1+ mapping and (2) B1+ mapping using linear combinations of transmit channels. In this work, both approaches are combined and interferometric Bloch-Siegert B1+ mapping is introduced. This approach is cross-validated against two recently introduced interferometric B1+ mapping methods based on actual flip angle imaging (AFI) and a multi flip-angle pre-pulse method as well as against single-channel AFI based B1+ mapping.

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Keywords

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