Single breath-hold whole-heart MRA using variable-density spirals at 3T.
Multislice breath-held coronary imaging techniques conventionally lack the coverage of free-breathing 3D acquisitions but use a considerably shorter acquisition window during the cardiac cycle. This produces images with significantly less motion artifact but a lower signal-to-noise ratio (SNR). By using the extra SNR available at 3 T and undersampling k-space without introducing significant aliasing artifacts, we were able to acquire high-resolution fat-suppressed images of the whole heart in 17 heartbeats (a single breath-hold). The basic pulse sequence consists of a spectral-spatial excitation followed by a variable-density spiral readout. This is combined with real-time localization and a real-time prospective shim correction. Images are reconstructed with the use of gridding, and advanced techniques are used to reduce aliasing artifacts.
Santos
Juan M
JM
Magnetic Resonance Systems Research Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA. jmsantos@mrsrl.stanford.edu
Cunningham
Charles H
CH
Lustig
Michael
M
Hargreaves
Brian A
BA
Hu
Bob S
BS
Nishimura
Dwight G
DG
Pauly
John M
JM
D016477:Artifacts; D017023:Coronary Angiography / Q000379:methods*; D006321:Heart / Q000033:anatomy & histology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography / Q000379:methods*