Prospective MR signal-based cardiac triggering.
A cardiac motion compensation method using magnetic resonance signal-based triggering is presented. The method interlaces a triggering pulse sequence with an imaging sequence. The triggering sequence is designed to measure aortic blood velocity, from which cardiac phase can be inferred. The triggering sequence is executed repeatedly and the acquired data processed after each sequence iteration. When the desired phase of the cardiac cycle is detected, data are acquired using the imaging sequence. A signal-processing unit of a conventional scanner is used to process the triggering data in real time and issue triggering commands. Alternatively, a workstation, with a bus adaptor, can access data as they are acquired, process and display the data, and issue triggering commands. With a graphical user interface, the triggering pulse sequence and data-processing techniques can be modified instantaneously to optimize triggering. The technique is demonstrated with coronary artery imaging using both conventional two-dimensional Fourier transform scans and spiral trajectories.
Vasanawala
S S
SS
Department of Electrical Engineering, Stanford University, CA 94305-9510, USA. vasanawala@stanford.edu
Sachs
T S
TS
Brittain
J H
JH
Meyer
C H
CH
Nishimura
D G
DG
D001013:Aorta, Thoracic / Q000033:anatomy & histology; D001783:Blood Flow Velocity / Q000502:physiology; D003199:Computer Systems; D004562:Electrocardiography / Q000295:instrumentation*; D005583:Fourier Analysis; D006321:Heart / Q000033:anatomy & histology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D011446:Prospective Studies; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*