Vascular vector flow mapping for ultrasonic two-dimensional flow estimation

Abstract

Vector flow mapping (VFM) is an echocardiographic approach for visualizing two-dimensional cardiac flow dynamics by estimating the radial component of flow from the Doppler velocities and wall motion velocities using mass-conservation equations. Although VFM provides two-dimensional flow in a clinically suitable, fast, and easy manner, it is only applicable to bounded regions such as ventricles. In this study, the VFM algorithm is modified so that the velocities are estimated regardless of the flow geometry. The proposed method, vascular VFM, operates on the same principle as VFM but with additional boundary conditions created by using Doppler velocities measured at a different steering angle. The method was optimized and validated using a common carotid artery phantom and particle-image-velocimetry (PIV). The results indicated that the optimal angle of an additional Doppler beam ranged from 10 to 20 degrees. Under this optimal-beam-angle condition, the standard deviation (SD) of total vascular VFM error,...