Importance of k-space trajectory on Off resonance artifact in echo-planar velocity imaging

Table 1 Peak velocity and flow quantification.

	Trajectory	Top-Down	Top-Down	Center-Out	Center-Out
	Off Resonance	0 Hz	100Hz	0 Hz	100Hz
Peak Velocity (cm/s)	Simulation	135.7	135.7 (no change)	135.7	129.8 (+11.7%)
	Phantom	137.5	138.8 (+0.9%)	138.5	133.2 (-3.8%)
	Volunteer	140.4	146.3 (+4.2%)	134.3	147.6 (+9.9%)
Flow (ml/s)	Phantom	484.7	487.1 (+0.5%)	496.3	838.7 (+69%)

Flow quantification for the off resonant center-out trajectory due to the spreading of the velocity over a larger ROI. The peak velocity is surprisingly only slightly underestimated with off-resonant center-out trajectory. Phantom experiments with an ideally homogenous signal intensity showed the magnitude signal intensity standard deviation didn&#8217t increase greatly with off-resonance top-down trajectory (5.2@0Hz to 8.3@100Hz) while it did for the center-out trajectory (13.0@0Hz to 39.3@100Hz).

ISSN: 1532-429X