de.mpg.escidoc.pubman.appbase.FacesBean
English
 
Help Guide Disclaimer Contact us Login
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

A theoretical and experimental comparison of different techniques for B(1) mapping at very high fields

MPS-Authors
http://pubman.mpdl.mpg.de/cone/persons/resource/persons84145

Pohmann,  R
Department High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Max Planck Society;

http://pubman.mpdl.mpg.de/cone/persons/resource/persons84187

Scheffler,  K
Department High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Max Planck Society;

Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Pohmann, R., & Scheffler, K. (2013). A theoretical and experimental comparison of different techniques for B(1) mapping at very high fields. NMR in Biomedicine, 26(3), 265–275. doi:10.1002/nbm.2844.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0013-B4AA-A
Abstract
With the increasing use of ultrahigh-field MR with multiple transmit channels, mapping of the B1+ field has become a critical factor in many studies, leading to the publication of a large number of sequences for the measurement of the flip angle in recent years. In this article, the accuracy, precision and practicability of some of the most prominent of these techniques are investigated both theoretically, using error propagation computations and Monte-Carlo simulations, and experimentally for different settings. For an exemplary experiment, which is typical for high-field applications, the flip angle uncertainty is calculated and measured for two- and three-dimensional acquisitions for techniques based on both magnitude and phase data. Simulated and measured results show good agreement. An experimental assessment of T1 and B0 dependence yields weak variations with these parameters for only a few of the sequences. Measurements on human scanners show crucial influences of specific absorption rate limitations, especially at ultrahigh field.