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Color Flow Imaging Basics: Differentiating Blood Flow Patterns

The multicolored patterns quickly moving across the screen can be quite confusing to the learner. Concentrating on just one chamber at a time, and in one part of the cardiac cycle makes it easier to separate color changes. For example, if you are trying to identify mitral regurgitation in an apical four-chamber view, focus on the left atrium in systole, and look for blood flow moving away from the transducer. Cine loops aid in distinguishing systolic from diastolic blood flow by analyzing the stored color flow image in a looping format, or one frame at a time.   Cardiac Doppler: Color Flow Imaging: Study Content Color Flow Imaging Basics: Summary Color flow imaging is a form of PW Doppler that shows the spatial orientation of blood flow superimposed on the 2-D or M-mode anatomy. Motion toward the transducer displays in hues above the color bar baseline; motion away from the transducer is displayed in hues below the color bar baseline Although reds generally indicate blood flow moving toward the transducer, and blues generally indicate blood flow moving away from he transducer, always check the color bar for the toward/away orientation. The distance of the color from the color bar baseline determines relative mean velocity. Colors close to the baseline have lower velocity flow. The farther away from the baseline the higher the blood velocity. Aliasing appears as color reversal. Laminar blood flow produces a homogeneous color pattern, while turbulent blood flow produces a disorganized, mosaic color pattern. To accurately assess blood flow, thoroughly interrogate the third dimension of each imaging view. Focus on one chamber at a time. First, identify the normal blood flow patterns, then the abnormal.