title: Comparison between eight- and sixteen-channel TEM transceive arrays for body imaging at 7 T.
abstract: Eight- and sixteen-channel transceive stripline/TEM body arrays were compared at 7 T (297 MHz) both in simulation and experiment. Despite previous demonstrations of similar arrays for use in body applications, a quantitative comparison of the two configurations has not been undertaken to date. Results were obtained on a male pelvis for assessing transmit, signal to noise ratio, and parallel imaging performance and to evaluate local power deposition versus transmit B(1) (B(1) (+) ). All measurements and simulations were conducted after performing local B(1) (+) phase shimming in the region of the prostate. Despite the additional challenges of decoupling immediately adjacent coils, the sixteen-channel array demonstrated improved or nearly equivalent performance to the eight-channel array based on the evaluation criteria. Experimentally, transmit performance and signal to noise ratio were 22% higher for the sixteen-channel array while significantly increased reduction factors were achievable in the left-right direction for parallel imaging. Finite difference time domain simulations demonstrated similar results with respect to transmit and parallel imaging performance, however, a higher transmit efficiency advantage of 33% was predicted. Simulations at both 3 and 7 T verified the expected parallel imaging improvements with increasing field strength and showed that, for a specific B(1) (+) shimming strategy used, the sixteen-channel array exhibited lower local and global specific absorption rate for a given B(1) (+) .
authors.affiliation: Department of Radiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: C J
authors.initials: CJ
authors.lastname: Snyder
authors.forename: L
authors.initials: L
authors.lastname: Delabarre
authors.forename: S
authors.initials: S
authors.lastname: Moeller
authors.forename: J
authors.initials: J
authors.lastname: Tian
authors.forename: C
authors.initials: C
authors.lastname: Akgun
authors.forename: P-F
authors.initials: PF
authors.lastname: Van de Moortele
authors.forename: P J
authors.initials: PJ
authors.lastname: Bolan
authors.forename: K
authors.initials: K
authors.lastname: Ugurbil
authors.forename: J T
authors.initials: JT
authors.lastname: Vaughan
authors.forename: G J
authors.initials: GJ
authors.lastname: Metzger
mesh_terms: D003198:Computer Simulation; D004867:Equipment Design; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D015233:Models, Statistical; D010388:Pelvis / Q000033:anatomy & histology*
references.citation: Magn Reson Med. 2003 Apr;49(4):655-64
references.pmid: 12652536
references.citation: Nature. 2009 Feb 19;457(7232):994-8
references.pmid: 19225521
references.citation: Neuroimage. 2009 Feb 15;44(4):1259-66
references.pmid: 19027861
references.citation: Neuroimage. 2009 Jun;46(2):432-46
references.pmid: 19233292
references.citation: Eur Radiol. 2011 Apr;21(4):841-9
references.pmid: 20872006
references.citation: Magn Reson Med. 2009 Jan;61(1):244-8
references.pmid: 19097214
references.citation: Magn Reson Med. 2005 Dec;54(6):1503-18
references.pmid: 16270333
references.citation: Magn Reson Med. 2004 Nov;52(5):953-64
references.pmid: 15508167
references.citation: Proc Natl Acad Sci U S A. 2007 Jul 10;104(28):11796-801
references.pmid: 17586684
references.citation: Magn Reson Med. 2008 Mar;59(3):590-7
references.pmid: 18219635
references.citation: Neuroimage. 2005 Feb 1;24(3):738-50
references.pmid: 15652309
references.citation: Magn Reson Med. 2008 Feb;59(2):396-409
references.pmid: 18228604
references.citation: Magn Reson Med. 2002 May;47(5):982-9
references.pmid: 11979578
references.citation: Magn Reson Med. 2003 Jan;49(1):144-50
references.pmid: 12509830
references.citation: Magn Reson Med. 2005 Feb;53(2):434-45
references.pmid: 15678527
references.citation: Magn Reson Med. 2008 Oct;60(4):895-907
references.pmid: 18816810
references.citation: Magn Reson Med. 2007 Feb;57(2):308-18
references.pmid: 17260370
references.citation: Magn Reson Med. 2009 Jan;61(1):136-44
references.pmid: 19097221
references.citation: J Magn Reson Imaging. 2010 Mar;31(3):740-6
references.pmid: 20187221
references.citation: Magn Reson Med. 2007 Dec;58(6):1294-8
references.pmid: 17957777
references.citation: Magn Reson Med. 2001 Jul;46(1):24-30
references.pmid: 11443707
references.citation: Phys Med Biol. 2010 Jan 21;55(2):N23-38
references.pmid: 20019402
references.citation: Magn Reson Med. 2007 Jan;57(1):192-200
references.pmid: 17191242
references.citation: Magn Reson Med. 1999 Nov;42(5):952-62
references.pmid: 10542355
references.citation: Magn Reson Med. 2006 Jul;56(1):157-66
references.pmid: 16724302
references.citation: Magn Reson Med. 2006 Dec;56(6):1274-82
references.pmid: 17075852
references.citation: Magn Reson Med. 2009 Dec;62(6):1379-84
references.pmid: 19859918
references.citation: J Comput Assist Tomogr. 1999 Nov-Dec;23(6):850-6
references.pmid: 10589558
references.citation: Magn Reson Med. 2009 Mar;61(3):517-24
references.pmid: 19097233
references.citation: Proc Natl Acad Sci U S A. 2008 Jul 29;105(30):10607-12
references.pmid: 18641121
references.citation: Neuroimage. 2007 Oct 1;37(4):1161-77
references.pmid: 17702606
references.citation: Magn Reson Med. 2006 Sep;56(3):620-9
references.pmid: 16894579
references.citation: Magn Reson Med. 2009 Feb;61(2):315-34
references.pmid: 19165885
references.citation: Magn Reson Imaging. 1998 Nov;16(9):1057-73
references.pmid: 9839990
references.citation: Magn Reson Med. 2004 Oct;52(4):851-9
references.pmid: 15389967
references.citation: Phys Med Biol. 2009 Mar 7;54(5):1253-64
references.pmid: 19182321
references.citation: Magn Reson Med. 2003 Nov;50(5):1018-30
references.pmid: 14587013
references.citation: Magn Reson Med. 2008 Jun;59(6):1355-64
references.pmid: 18506800