Doppler color flow /dop″lər/ [Christian J. Doppler, Austrian physicist and mathematician, 1803–1853] , an ultrasonic technique for detecting anatomical details by color coding of velocity shifts. In cardiography blood flowing in one direction appears red, and blood flowing in the opposite direction appears blue. The technique can also indicate the velocity of red blood corpuscles moving through the circulatory system, which makes it possible to quantify the flow, measure the pressures within the heart chambers, and calculate the stroke volume. In laparoscopy, Doppler color flow allows for rapid identification and differentiation of ducts and valves in the viscera, particularly in detection and diagnosis of pancreatic and liver tumors and colorectal liver metastases. See also Doppler ultrasonography.