Stephan Orzada1,2, Stefan Maderwald1,3,
Benedikt A. Poser1,4, Sren Johst1,2, Mark E. Ladd1,2,
Stephan Kannengiesser5, Andreas K. Bitz1,2
1Erwin L. Hahn Institute
for Magnetic Resonance Imaging, Essen, NRW, Germany; 2Department
of Diagnostic & Interventional Radiology & Neuroradiology, University
Hospital Essen, Essen, NRW, Germany; 3University of
Duisburg-Essen, Essen, NRW, Germany; 4Donders Institute for Brain,
Cognition & Behaviour, Centre for Cognitive Neuroimaging, Radboud
University Nijmegen, Nijmegen, Netherlands; 5Siemens Healthcare
Sector, Erlangen, Germany
High static field strengths of 7 Tesla and above are challenging due to the severe B1 inhomogeneities caused by the short wavelength. Several methods have been proposed to tackle this problem including RF Shimming and Transmit SENSE. Recently, a technique called Time-Interleaved Acquisition of Modes (TIAMO) has been proposed to reduce the impact of B1 inhomogeneity. In this work the influence of TIAMO on the image contrast as well as on the time-averaged SAR at 7 Tesla is addressed in detail, showing that TIAMO is superior to RF shimming in terms of image homogeneity and SAR.
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