Yu-Chung N Cheng et al 2009 Phys. Med. Biol. 54 1169 doi:10.1088/0031-9155/54/5/005
Yu-Chung N Cheng1,3, Jaladhar Neelavalli2 and E Mark Haacke1
Show affiliationsA discrete Fourier based method for calculating field distributions and local magnetic susceptibility in MRI is carefully studied. Simulations suggest that the method based on discrete Green's functions in both 2D and 3D spaces has less error than the method based on continuous Green's functions. The 2D field calculations require the correction of the 'Lorentz disk', which is similar to the Lorentz sphere term in the 3D case. A standard least-squares fit is proposed for the extraction of susceptibility for a single object from MR images. Simulations and a phantom study confirm both the discrete method and the feasibility of the least-squares fit approach. Finding accurate susceptibility values of local structures in the brain from MR images may be possible with this approach in the future.
For more information on this article, see medicalphysicsweb.org
87.61.Tg Clinical applications
02.70.Rr General statistical methods
87.50.C- Static and low-frequency electric and magnetic fields effects
Issue 5 (7 March 2009)
Received 23 October 2008, in final form 10 January 2009
Published 30 January 2009
Yu-Chung N Cheng et al 2009 Phys. Med. Biol. 54 1169
Harald Schöndube et al 2009 Phys. Med. Biol. 54 4625
Th Kraus et al 1997 J. Micromech. Microeng. 7 196
P W Anderson et al 2004 J. Phys.: Condens. Matter 16 R755
Andrey V Chubukov et al 1996 J. Phys.: Condens. Matter 8 10017
Vadim N. Gamezo et al. 2005 ApJ 623 337
F. K. Röpke 2007 ApJ 668 1103
Jeffrey R. Forshaw et al JHEP10(2001)007
S. Perlmutter et al. 1999 ApJ 517 565
Tom Timusk and Bryan Statt 1999 Rep. Prog. Phys. 62 61