Conventional echo color Doppler versus ULA-OP in the assessment of venous flow model

The quantification of venous flows can be obtained by multiplying cross sectional area, measured on a B-mode video-clip, by velocity values, obtained with Doppler measurements. The Doppler angle between ultrasound (US) line and blood flow requires a manual adjustment. Establishing this parameter is critical in order to calculate blood velocity. However, the operator dependency gives high variable results. It is worth noting that a new class of vector Doppler devices can enhance the accuracy and precision of measurements. Such technology uses a double US line that leads to automatically know the Doppler angle. By comparing in an in vitro model of venous flow conventional echo color Doppler (ECD) equipment with the new device, we found a better minimal difference between the latter and the nominal flow rate (20%). On the contrary, the comparison with conventional ECD showed a difference ranging between 2% and 43%, according to the possible settings of the equipment. Our study demonstrates a better accuracy of the experimental device with respect to conventional ECD in measuring the venous flow rate.