Accuracy of arterial pulse-wave velocity measurement using MR

The performance of a one-dimensional MR technique for the estimation of pulse-wave velocity in the aorta was evaluated. An expression for the error in this estimate was formulated and verified both by simulation and by experiment. On the basis of this formulation, guidelines for increasing the efficiency of the acquisition were established. The technique was further validated by comparison with pulse-wave velocity measurements made with a pressure catheter. All data were acquired from a latex tube driven by a pulsatile flow system. MR measurements of pulse-wave velocity in the tube were found to be very reproducible in the presence of white noise. Measurements by other techniques were in good agreement, falling within 2 SD of the mean. Because of its sensitivity and spatial resolution, this technique shows promise for making spatially resolved estimates of vessel distensibility. This would allow assessment of diseases, such as atherosclerosis, that cause local changes in the material properties of the vasculature.