Contrast medium assisted fluid flow measurements

摘要

In this paper the development and evaluation of two new approachesnfor ultrasound time-domain fluid flow measurements by tracking echoesnscattered by a contrast agent following injection of a bolus of thencontrast agent are described. Their feasibility was investigated bynmeasuring velocity or velocity profile of blood flowing in a mockncirculatory loop in vitro. Measurements were made with a one transducernintravessel approach and a two transducer extravessel approach. A hybridncluster or vector cross-correlation method was used to track the motionnof the scatterers in the two transducer time-domain method. This clusternor vector cross correlation method was developed to reduce the ambiguitynresulted from misregistration which is a common problem in targetntracking by correlating signal patterns. The experimental results show angood agreement between the measured data and those estimated from timingnthe volume. Although the discussions given in this paper pertain only tonblood flow measurements, there is no reason to indicate that thesenapproaches can not be used for fluid flow measurements in an industrialnenvironment if suitable contrast agents can be developed