Two-point interference method for suppression of ghost artifacts due to motion.
A two-point interference method is introduced for suppression of ghosting due to motion in magnetic resonance imaging. The method requires only two time-interleaved data acquisitions, without any monitoring of the motion. A postprocessing technique is used to produce a weighted sum of the two acquired images, in which ghosts are suppressed by interference through an automatic regional tuning procedure. The appropriate complex weighting factors are regionally chosen by minimizing the "gradient energy," which is defined as the sum of squared pixel values in the partial-derivative maps. The method was tested in both phantoms and volunteers with a variety of imaging protocols. The level of ghost suppression with the two-point method was found to be comparable to that of the three-point method described previously by the authors.
Xiang
Q S
QS
Department of Medical Biophysics, University of Toronto, Ontario, Canada.
Bronskill
M J
MJ
Henkelman
R M
RM
D016477:Artifacts; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008961:Models, Structural; D009068:Movement