Limits of time-of-flight magnetic resonance angiography.

Many of the limits to current time-of-flight (TOF) magnetic resonance (MR) angiographic methods, including flow voids from turbulent flow, flow artifacts from pulsatile flow, and oblique flow displacement, are not inherent to the TOF enhancement mechanism and will be eliminated with technological advancements. Slowly flowing blood and physiological motion will remain an obstacle to these methods, although technological advancements will improve on current methods. Future TOF MR angiographic methods will prove to be a cost-effective competitor to MR angiographic methods requiring contrast agents in many applications.