Reduction of phase error ghosting artifacts in thin slice fast spin-echo imaging.
Fast spin-echo (FSE) imaging techniques are very sensitive to the relative phase between the 90 degrees (excitation) RF pulse and the 180 degrees (refocusing) RF pulses. In this paper, it is demonstrated that a phase shift can be created between the excitation and refocusing pulses in such a manner that the received signal is divided into two components of distinctly different phase shifts. The nature of these two components is reviewed. It is demonstrated that ghosting artifacts will occur when images are reconstructed from this received signal. The ghosting is shown to be object dependent. A correction technique is presented which calculates the phase errors among different echoes based on measurements from a single echo train acquired without phase encoding gradients. The results in both phantom and human studies show that this method is capable of reducing the ghosting artifact in thin slice FSE images.
Department of Radiology, University of Utah, Salt Lake City 84132, USA.
X
X
Wan
D L
DL
Parker
J N
JN
Lee
H R
HR
Buswell
G T
GT
Gullberg
D000465:Algorithms; D016477:Artifacts; D001921:Brain / Q000033:anatomy & histology; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008961:Models, Structural; D008962:Models, Theoretical; D011846:Radio Waves; D014867:Water
D014867:Water