Effects of Different Parameter Values on the Performance of CPWC-Based Local PWV Estimation

Local pulse wave velocity (PWV) is a widely accepted index for quantitatively evaluating the stiffness of regional arteries, its predictive value is important for assessing the risk of various cardiovascular diseases. High frame rates are required to capture the propagation of pulse wave because it travels at high speed. Plane wave technique, in which all transducer elements are excited at the same time for a full aperture transmission of the region of interest thereby creating a high frame rate, and therefore is suitable for local PWV estimation. However, there have been far less systematic studies focused on the effects of the number and transmission angles of plane waves on the performance of coherent plane wave compounding (CPWC)-based local PWV estimation. In this study, the quantitative effects of these two parameters are assessed by a carotid vessel phantom. First, the blood mimicking fluid is pumped through the phantom via CompuFlow1000. And the linear array probe is attached to the Verasonics system for data acquisition of 3 and 5 plane wave sequences with transmission angles ranging from 1° to 8° and an interval increment step of 1°. The local PWV is then estimated by repeatable and robust ultrasonic transit time method The quantitative effects of different configurations on the performance are assessed by mean values and standard deviations of the estimated local PWVs. The results show that 3 plane waves with transmission angles of (−1°, 1°, 0°) is the best configuration by providing the optimal performance for local PWV estimation. The quantitative findings can provide important advice and improve direction for the CPWC-based local PWV estimation.