Methof for determining true magnitude of blood velocity

摘要

A method for assessing and displaying the true three dimensional magnitude of fluid velocity using ultrasonic imaging signals is disclosed. Fluid, such as blood, flowing through a vessel is subjected to ultrasound imaging signals using a transducer. Axial velocity of fluid motion in relation to the transducer beam is then determined from the imaging signals. Next, a region of laminar flow is identified using the axial velocity. Lateral transit time in the region of laminar flow is then estimated as an indication of velocity in the direction perpendicular to the transducer beam. The three dimensional velocity magnitude is then estimated using the lateral transmit time and the total distance across the lateral beam width, or by using the beam to vessel angle which is estimated using the lateral transit time. The estimated three dimensional velocity is then displayed as a numerical representation or as an image as a two dimensional waveform as a function of time or as a color flow map where the velocity magnitude is represented by different colors and/or intensity of color.