title: On the nature and reduction of the displacement artifact in flow images.
abstract: In flow-imaging experiments with 2-D Fourier transform sequences, the time difference between phase encoding and readout leads to a potentially misleading displacement artifact. This artifact arises in regions of rapid flow and high shear, and manifests as an intensity distortion in addition to a bulk shift. We have studied methods of mitigating the artifact, including offset-echo acquisition, backward-evolving phase encoding, moment-compensated phase encoding, and projection-reconstruction imaging. Experiments on flow phantoms verified the nature and reduction of this displacement artifact. Of the four methods studied, the projection-reconstruction sequence proved to be the most effective, completely eliminating the artifact.
authors.affiliation: Department of Electrical Engineering, Stanford University, California 94305.
authors.forename: D G
authors.initials: DG
authors.lastname: Nishimura
authors.forename: J I
authors.initials: JI
authors.lastname: Jackson
authors.forename: J M
authors.initials: JM
authors.lastname: Pauly
mesh_terms: D016477:Artifacts; D005583:Fourier Analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008961:Models, Structural