Title:
核磁気共鳴撮像装置およびＲＦシミング方法
Document Type and Number:
Japanese Patent JP6527138
Kind Code:
B2
Abstract:
The present invention provides an RF shimming method for a nuclear magnetic resonance imaging apparatus comprising: a transmission coil having a plurality of channels that respectively transmit high frequencies to an object and a calculation unit performing RF shimming calculation that determines at least one of amplitudes and phases of the high frequencies to be transmitted respectively to a plurality of the channels so as to improve homogeneity of a high-frequency magnetic field distribution generated by the transmission coil and reduce a specific absorption ratio of the object. Objective function parameters for setting the objective function are determined according to contribution to the SAR for each of the channels during the RF shimming calculation based on the objective function and the restriction condition.
Inventors:
Kosuke Ito
Application Number:
JP2016513693A
Publication Date:
June 05, 2019
Filing Date:
March 25, 2015
Export Citation:
Assignee:
株式会社日立製作所
International Classes:
A61B5/055
Domestic Patent References:
| JP2012502683A | ||||
| JP2003505046A |
Foreign References:
| WO2014021172A1 | ||||
| US20100301859 | ||||
| US20080238425 | ||||
| US20130251227 | ||||
| US20100253344 | ||||
| US20080100292 | ||||
| US20050231203 |
Other References:
Tang, Lin,Studies of RF Shimming Techniques with Minimization of RF Power Deposition and Their Associated Temperature Changes,Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering,2011年 2月,Vol.39B, No.1,p.11-25
Attardo, Elia Amedeo,Field synthesis in inhomogeneous media:Joint control of polarization, uniformity and SAR in MRI B1-field,Progress In Electromagnetics Research,2011年,Vol.118,p.355-377
R. Lattanzi,Electrodynamic analysis of SAR and transmit homogeneity for RF shimming on a dielectric cylinder,Proc.Intl.Soc.Mag.Reson.Med.,2009年,Vol.17,p.4510
BOB VAN DEN BERGEN,7 T BODY MRI: B1 SHIMMING WITH SIMULTANEOUS SAR REDUCTION,PHYSICS IN MEDICINE AND BIOLOGY,2007年 9月 7日,Vol.52,No.17,P.5429-5441
P.Balchandani, M.M.Khalighi, S.S.Hsieh, K.Setsompop, J.Pauly,and D.Spielman,Adiabatic B1 Shimming Algorithm for Multiple Channel Transmit at 7T,Proc.Intl.Soc.Mag.Reson.Med.,2011年 7月13日,vol.19,p2907
Attardo, Elia Amedeo,Field synthesis in inhomogeneous media:Joint control of polarization, uniformity and SAR in MRI B1-field,Progress In Electromagnetics Research,2011年,Vol.118,p.355-377
R. Lattanzi,Electrodynamic analysis of SAR and transmit homogeneity for RF shimming on a dielectric cylinder,Proc.Intl.Soc.Mag.Reson.Med.,2009年,Vol.17,p.4510
BOB VAN DEN BERGEN,7 T BODY MRI: B1 SHIMMING WITH SIMULTANEOUS SAR REDUCTION,PHYSICS IN MEDICINE AND BIOLOGY,2007年 9月 7日,Vol.52,No.17,P.5429-5441
P.Balchandani, M.M.Khalighi, S.S.Hsieh, K.Setsompop, J.Pauly,and D.Spielman,Adiabatic B1 Shimming Algorithm for Multiple Channel Transmit at 7T,Proc.Intl.Soc.Mag.Reson.Med.,2011年 7月13日,vol.19,p2907
Attorney, Agent or Firm:
Polaire Patent Business Corporation