Ultrasound is a simple, fast and non-invasive exam that is radiation-free. It uses an ultrasound beam to create an image. It is the preferred exam for front-line investigation of many pathologies, among them those of the liver, gall bladder and bile duct, pancreas, spleen, both kidneys, large blood vessels, pelvic area and certain targeted digestive pathologies such as appendicitis, diverticulitis and illeitis. Doppler allows for a more specific study of the cardiovascular circulation, especially in cases of arterial and portal hypertension and mesenteric angina.