Doppler ultrasound remained a minority imaging methodology until the introduction of colour Doppler in 1982. In this technique, the motion of the blood is colour coded and superimposed on the B-mode image. This allows rapid visualisation of the flow patterns in vessels, allowing high-velocity jets in arteries and in cardiac chambers to be seen. It quickly became apparent that the ability to visualise flow patterns, such as the presence of intracardiac jets, was of great value. In addition, it considerably speeded up the placement of the Doppler sample volume in spectral Doppler investigation, hence reducing scanning time.