ABSTRACT
Contrast-enhanced MRA has emerged as a robust and reliable alternative to ow-dependent imaging techniques, and it can be performed in seconds rather than minutes. Contrast between blood vessels and background is achieved by shortening the T1 relaxation time of blood with a paramagnetic contrast material. However, one of the greatest challenges of contrast-enhanced MRA is achieving optimal timing of the contrast agent bolus and limiting venous contamination. In the peripheral extremities, timing of the bolus is particularly challenging. Test bolus
timing examinations and bolus tracking techniques may be limited because small vessel opacication may be obscured by inow effects.
