9.4T human MRI: preliminary results.
This work reports the preliminary results of the first human images at the new high-field benchmark of 9.4T. A 65-cm-diameter bore magnet was used together with an asymmetric 40-cm-diameter head gradient and shim set. A multichannel transmission line (transverse electromagnetic (TEM)) head coil was driven by a programmable parallel transceiver to control the relative phase and magnitude of each channel independently. These new RF field control methods facilitated compensation for RF artifacts attributed to destructive interference patterns, in order to achieve homogeneous 9.4T head images or localize anatomic targets. Prior to FDA investigational device exemptions (IDEs) and internal review board (IRB)-approved human studies, preliminary RF safety studies were performed on porcine models. These data are reported together with exit interview results from the first 44 human volunteers. Although several points for improvement are discussed, the preliminary results demonstrate the feasibility of safe and successful human imaging at 9.4T.
Vaughan
Thomas
T
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA. tommy@cmrr.umn.edu
DelaBarre
Lance
L
Snyder
Carl
C
Tian
Jinfeng
J
Akgun
Can
C
Shrivastava
Devashish
D
Liu
Wanzahn
W
Olson
Chris
C
Adriany
Gregor
G
Strupp
John
J
Andersen
Peter
P
Gopinath
Anand
A
van de Moortele
Pierre-Francois
PF
Garwood
Michael
M
Ugurbil
Kamil
K
D002058:Burns, Electric / Q000209:etiology / Q000517:prevention & control; D004244:Dizziness / Q000209:etiology / Q000517:prevention & control; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation* / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D010865:Pilot Projects; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods; D018570:Risk Assessment; D014159:Transducers