An asymmetric slice profile: spatial alteration of flow signal response in 3D time-of-flight NMR angiography.
We introduce an asymmetric slice profile technique, which alters the spatial response of the flow signal in 3D time-of-flight NMR angiography. By gradually increasing the flip angle from the inflow to the outflow portions of the slab, the inflow refreshment effect is distributed over a wide slab thickness. The asymmetric slice profile is simply produced by using a Gaussian RF excitation with an overlapping presaturation. The spatial distribution of steady flow signal in a phantom study demonstrated an essential agreement with a numerical simulation. 3D time-of-flight NMR angiography of volunteers' heads using this technique provided a smooth vascular depiction over a wide slab thickness.
Matsuda
T
T
Department of Internal Medicine, Kyoto University, Japan.
Morii
I
I
Kohno
F
F
Asato
R
R
Ikezaki
Y
Y
Yoshitome
E
E
Sasayama
S
S
D001808:Blood Vessels / Q000033:anatomy & histology*; D003198:Computer Simulation; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008955:Models, Cardiovascular; D008961:Models, Structural