Signal behavior in continuously ramped 2D TrueFISP for whole-body imaging.
A fast and robust imaging technique was developed based on a single-slice TrueFISP acquisition using a slice excitation frequency that is incremented, or spatially "ramped," with each repetition. The short acquisition time of single slices allows artifact-free imaging during free breathing, which demonstrates the potential use of this technique for whole-body screening. Overlapping positioning of consecutively acquired slices was used to provide gapless volume coverage in free-breathing measurements. The image contrast of ramped TrueFISP was analyzed in detail using simulations and experiments. A high ramp speed results in an increased overall signal intensity and in a modification of the known T(2)/T(1) contrast towards a proton density-weighted contrast. A further increase in imaging speed is achieved with z-interleaved phase-encoding trajectories based on weighted transitions between adjacent views.
Fautz
Hans-Peter
HP
University Hospital of Freiburg, Radiology, Section of Medical Physics, Freiburg, Germany. fautz@nz11.ukl.uni-freiburg.de
Leupold
Jochen
J
Hennig
Jürgen
J
Scheffler
Klaus
K
D003287:Contrast Media; D005583:Fourier Analysis; D018594:Human Body; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement; D012016:Reference Values; D012680:Sensitivity and Specificity
D003287:Contrast Media