%0 Journal Article
%A Joris Hubmann, Max
%A Orzada, Stephan
%A Kowal, Robert
%A Anton Grimm, Johannes
%A Speck, Oliver
%A Maune, Holger
%T Towards Large Diameter Transmit Coils for 7-T Head Imaging: A Detailed Comparison of a Set of Transmit Element Design Concepts.
%J NMR in biomedicine
%V 38
%N 5
%@ 0952-3480
%C New York, NY
%I Wiley
%M DKFZ-2025-00720
%P e70030
%D 2025
%X Many different transmit (Tx) coil concepts and designs for 7-T magnetic resonance imaging of the head have been proposed. Most of them are placed close to the head and in combination with the receive coils creating a helmet-like structure. This limits the space for additional equipment for external stimuli. A large diameter transmit coil can increase the ease using supplementary measurement devices. Therefore, this study systematically evaluated nine different Tx elements regarding their performance within a large diameter transmit coil with a diameter > 
%X <br clear="all" /><table border="0" width="100%"><tr><td>
%X <table align="center" cellspacing="0"  cellpadding="2"><tr><td nowrap="nowrap" align="center">
%X   >  </td></tr></table>
%X </td></tr></table>
%X 
%X  350 mm. Each Tx element was examined regarding its power and specific absorption rate (SAR) efficiencies, its loading dependence, intrinsic decoupling, and its radio frequency (RF) shimming capability. Additionally, an experimental validation of  -  B 1 +  -  
%X <br clear="all" /><table border="0" width="100%"><tr><td>
%X <table align="center" cellspacing="0"  cellpadding="2"><tr><td nowrap="nowrap" align="center">
%X   | B<sub>1</sub><sup>+</sup> | </td></tr></table>
%X </td></tr></table>
%X 
%X  -maps was performed. The loop-based Tx elements (circular and rectangular loop) provided the highest power and SAR efficiency with at least 15.5
%K Magnetic Resonance Imaging: instrumentation
%K Head: diagnostic imaging
%K Equipment Design
%K Humans
%K Phantoms, Imaging
%K Brain: diagnostic imaging
%K 7 T MRI (Other)
%K EM simulations (Other)
%K RF coils (Other)
%K RF shimming (Other)
%K UHF (Other)
%K antennas (Other)
%K hardware (Other)
%K head imaging (Other)
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:40186518
%2 pmc:PMC11971727
%R 10.1002/nbm.70030
%U https://inrepo02.dkfz.de/record/300267