Andreas K. Bitz1,2, Irina Brote1,2,
Stephan Orzada1,2, Oliver Kraff1,2, Stefan Maderwald1,2,
Harald H. Quick3, Klaus Solbach4, Achim Bahr5,
Hans-Peter Fautz6, Franz Schmitt6, Mark E. Ladd1,2
1Erwin L. Hahn Institute for MRI,
University Duisburg-Essen, Essen, Germany; 2Department of
Diagnostic and Interventional Radiology and Neuroradiology, University
Hospital Essen, Essen, Germany; 3Institute for Medical Physics,
Friedrich-Alexander-University, Erlangen-Nuernberg, Germany; 4High
Frequency Technique, University Duisburg-Essen, Duisburg, Germany; 5IMST
GmbH, Kamp-Lintfort, Germany; 6Siemens Healthcare Sector,
Erlangen, Germany
The
aim of this study was to compare RF shimming procedures based on RF
simulations and measured B1+ maps for different ROIs in the thorax and
abdomen of volunteers with varying physique. Simulation-based RF shims were
computed by use of heterogeneous body models. In vivo B1+ mapping was
performed during breath hold by utilization of a pre-saturation turboFLASH.
ROIs in the heart, liver, and kidney were considered. Appropriate
simulation-based shims could be derived which function in the majority of
considered volunteers. If the numerical body model inadequately describes the
subjects body, measured shims should be preferred to achieve higher image
quality.
Keywords