NEW METHOD FOR QUANTITATIVELY DETERMINING AORTIC REGURGITANT VOLUME USING DOPPLER COLOR-FLOW IMAGING - EXPERIMENTAL VALIDATION-STUDY

We have developed a method to provide the two-dimensional distribution of blood flow velocity a the blood flow volume rate in the ascending aorta from the cross-sectional Doppler color flow image. Regional bloo d flow velocities were determined by converting color intensities of t he cross-sectional Doppler color flow image into the corresponding flo w velocities with the correction with the spatial ultrasound beam inci dent angle. The spatial ultrasound beam incident angle was estimated f rom the geometric characteristics of the color flow image contour. The method was validated in a steady flow model circuit comparing the cal culated flow volume rates by the method with those simultaneously meas ured by an electromagnetic flowmeter. We performed an open chest dog e xperiment and calculated the blood flow volume rate at the ascending a orta before and after the aortic regurgitation was made. The calculate d ejection flow volume rate and regurgitant volume were validated by t he comparison with those simultaneously measured by an electromagnetic flowmeter. Based on these data, we can conclude that the current meth od provides accurate measurements of regurgitant volume as well as eje ction flow volume rate in the ascending aorta.