Colour Doppler ultrasound is a non-invasive imaging technique that uses sound waves to visualize blood flow through the body’s veins and arteries. It provides detailed images of blood vessels and identifies issues like blockages, clots, or reduced blood flow. This test is especially useful for diagnosing conditions related to heart, vascular, or peripheral circulation problems. Patients should opt for a Colour Doppler when experiencing symptoms like leg pain, swelling, or varicose veins, or when monitoring blood flow after surgery.