Effect of Background Velocity Error on Measured Time of End-systole in Patients with Aortic Regurgitation by Phase Contrast MRI
Lloyd S, Gupta H
University of Alabama at Birmingham
Velocity mapping by phase contrast MRI is often used to measure the regurgitant volume in aortic regurgitation, which may be used to grade the severity. This requires calculating the time integral of the diastolic flow velocity. The limits of integration (i.e., systolic and diastolic durations) must therefore be accurately known. Background phase offsets result in small deviations in the measured velocities. We examined the effect of such shifts on the systolic duration. Analysis shows that small offsets of the order of 2 cm/s do not significantly affect the accuracy of systolic and diastolic duration measurements and may be neglected.