Non Contrast MR Angio by Intrinsic Dephasing of True FISP SMS: Ssfp Minus Ssfp

Michael Deimling¹, Alto Stemmer¹

We propose an SSFP (Steady State Free Precession) sequence scheme which is based on the intrinsic very high signal sensitivity of flow phase instabilities from TR to TR interval. A straight forward modification of a true FISP sequence makes the signal susceptible to fast flow of the arteries, but leaves the flow of venes untouched; by simply subtraction of both 3D data sets, an artery only image is created. The method does not need any kind of gating or triggering to separate veins from arteries as is needed in non-contrast enhanced MRA methods like Fresh Blood Imaging.