T1-weighted snapshot gradient-echo MR imaging of the abdomen.
Magnetization-prepared ultrashort-repetition-time (snapshot) gradient-echo imaging is a technique of magnetic resonance (MR) imaging with many potential applications. In the application of this technique to abdominal imaging, the effects on contrast of phase-encoding order, resolution, preparation-phase inversion time, and data-acquisition flip angle were predicted and then demonstrated with images obtained in examinations of 22 patients. In the analysis of 36 liver lesions, snapshot images were compared with corresponding T1-weighted spin-echo images on the basis of signal-to-noise ratio (S/N) of liver and contrast-to-noise ratio (C/N) between liver and lesion. Snapshot MR imaging produced abdominal images with 192 (or 256) x 256 resolution, negligible motion artifact, and C/N 1.29 times (+/- 0.48) higher than that in T1-weighted spin-echo imaging. Acquisition times were 13 seconds or less, short enough for imaging during suspended respiration. Also, use of a phased-array multicoil further improves the S/N in snapshot images without acquisition-time penalty.
Holsinger-Bampton
A E
AE
Magnetic Resonance Laboratory, Mayo Clinic, Rochester, MN 55905.
Riederer
S J
SJ
Campeau
N G
NG
Ehman
R L
RL
Johnson
C D
CD
D000005:Abdomen / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008099:Liver / Q000473:pathology*; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000556:secondary; D008279:Magnetic Resonance Imaging / Q000379:methods*; D013997:Time Factors