A Colour Doppler ultrasound is a special non invasive ultrasound technique that allows the doctor to see and evaluate blood flowing through arteries and veins in various parts of the body such as the abdomen, arms, legs, neck and brain or within various body organs such as the liver or kidneys.

Colour Doppler is a technique in which colours superimposed on an image of a blood vessel indicate the speed and direction of blood flow in the vessel. Colour Doppler test is a type of ultrasound test.

A Colour Doppler ultrasound is an imaging test that uses sound waves to show blood moving through blood vessels. Doppler ultrasound works by measuring sound waves that are reflected from moving objects, such as red blood cells. This is known as the Doppler effect. This ultrasound examination is usually completed within 30 to 45 minutes. Occasionally, complex examinations may take longer.