000K utf8 1100 2019$c2019-09-12 1500 eng 2050 urn:nbn:de:hbz:464-20191031-085157-2 2051 10.1371/journal.pone.0222452 3000 Orzada, Stephan 3010 Abuelhaija, Ashraf 3010 Bitz, Andreas K. 3010 Brunheim, Sascha 3010 Fiedler, Thomas M. 3010 Flöser, Martina 3010 Gratz, Marcel 3010 Johst, Sören 3010 Kraff, Oliver 3010 Ladd, Mark E. 3010 Maderwald, Stefan 3010 Oehmigen, Mark 3010 Quick, Harald H. 3010 Rietsch, Stefan H. G. 3010 Shooshtary, Samaneh 3010 Solbach, Klaus 3010 Voelker, Maximilian N. 4000 32-channel parallel transmit system add-on for 7T MRI [Orzada, Stephan] 4209 Purpose A 32-channel parallel transmit (pTx) add-on for 7 Tesla whole-body imaging is presented. First results are shown for phantom and in-vivo imaging. Methods The add-on system consists of a large number of hardware components, including modulators, amplifiers, SAR supervision, peripheral devices, a control computer, and an integrated 32-channel transmit/receive body array. B1+ maps in a phantom as well as B1+ maps and structural images in large volunteers are acquired to demonstrate the functionality of the system. EM simulations are used to ensure safe operation. Results Good agreement between simulation and experiment is shown. Phantom and in-vivo acquisitions show a field of view of up to 50 cm in z-direction. Selective excitation with 100 kHz sampling rate is possible. The add-on system does not affect the quality of the original single-channel system. Conclusion The presented 32-channel parallel transmit system shows promising performance for ultra-high field whole-body imaging. 4950 https://doi.org/10.1371/journal.pone.0222452$xR$3Volltext$534 4950 https://nbn-resolving.org/urn:nbn:de:hbz:464-20191031-085157-2$xR$3Volltext$534 4961 https://duepublico2.uni-due.de/receive/duepublico_mods_00070688 5051 610