Advances in cardiac applications of subsecond flash MRI.
Flow-suppressed, subsecond FLASH MR images of the normal human heart have been obtained from single cardiac cycles using a 2.0-T whole-body MRI/MRS system (Siemens Magnetom) equipped with conventional 10 mT m-1 gradients. The present results demonstrate further technical improvements as compared to a previous report on the same subject (Magn. Reson. Med. 13:150-157; 1990). Measuring times of 139 msec and 209 msec were achieved by reducing the repetition time to TR = 4.36 msec (TE = 2.8 msec) and the spatial resolution to 32 x 128 or 48 x 128 measured data points, respectively. The flip angle was optimized to 12 degrees. Spatial pre-saturation of 60 mm thick sections adjacent to the imaging plane resulted in a suppression of the blood signal and a clear delineation of the myocardium. Oblique rotation of the imaging slice provides convenient access to the anatomical long axis and short axis views of the heart. EKG-triggered images from separate heartbeats but at different cardiac phases demonstrate that the effective time resolution is considerably less than the actual imaging time.
Chien
D
D
Max-Planck-Institut für biophysikalische Chemie, Göttingen, FRG.
Merboldt
K D
KD
Hänicke
W
W
Bruhn
H
H
Gyngell
M L
ML
Frahm
J
J
D004562:Electrocardiography; D006321:Heart / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*