Figure 1.

Simplified pulse diagram for 2D TOF MRA. The time-of-flight MRA sequence consists of a field suppression preparatory component (black box) placed downstream to null the venous signal with a gradient echo sequence body. Blood flow demonstrates higher signal secondary to flow related enhancement (lack of saturation due to incoming fresh spin) as well as avoidance of flow related signal loss (from use of gradient echo-based sequence). TOF, time-of-flight; MRA, magnetic resonance angiography.