SPECTRAL AND COLOR DOPPLER SONOGRAPHIC APPLICATIONS OF A NEW TEST OBJECT WITH ADJUSTABLE MOVING TARGET SPACING

A new test object has been developed with the aim of covering a wide r ange of Doppler quality assurance requirements, with particular emphas is on color Doppler imaging (both velocity and power modes). The test object consists of a rotating string-loop, which provides the single v elocity source required for velocity calibration. The loop geometry pr ovides two targets with adjustable spacing, which move in opposite dir ections within the same scan plane, and the string material offers a n umber of desirable properties (absence of knot artifacts, small diamet er, uniform backscatter as a function of Doppler angle, and low attenu ation). Representative results are included to demonstrate application s of the test object in the assessment of velocity accuracy, intrinsic spectral broadening, spatial resolution, and sensitivity, as well as to discuss quality assurance and performance issues in the context of spectral and color Doppler sonography.