High-speed black blood imaging of vessel stenosis in the presence of pulsatile flow.
Stenosis phantoms were created to study the ability of "black blood" methods to image a vessel stenosis in the presence of pulsatile flow. Black blood images were acquired with a modified TurboFLASH (fast low-angle shot) method that eliminates flow signal by applying a set of prepulses before segmented data acquisition. With this high-speed approach, imaging can be completed within 16 seconds. This technique was compared with conventional spin-echo black blood, gradient-echo black blood, and gradient-echo bright blood methods. Loss of flow signal, which extended beyond the site of the stenosis, was seen on the gradient-echo bright blood images. The pattern of signal loss varied with the type of stenosis. Flow voids were achieved with spin-echo black blood imaging; however, substantial ghosting artifacts were seen. With gradient-echo black blood imaging, it was difficult to eliminate all flow signal, particularly for in-plane flow. The modified TurboFLASH method produced high-quality black blood images in a fraction of the time needed for spin-echo imaging. It showed no ghosting artifacts even in the presence of pulsatile flow.
Chien
D
D
Department of Radiology, Beth Israel Hospital, Boston, MA.
Goldmann
A
A
Edelman
R R
RR
D001783:Blood Flow Velocity; D001808:Blood Vessels / Q000473:pathology*; D003251:Constriction, Pathologic / Q000175:diagnosis; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008955:Models, Cardiovascular; D008961:Models, Structural; D011673:Pulsatile Flow; D013997:Time Factors; D014652:Vascular Diseases / Q000175:diagnosis*