Giant-cell arteritis is an inflammation of blood vessels on the sides of the forehead. It can cause headaches; tenderness of the scalp; pain in the side of the face that is worse with chewing; and swollen, tender forehead vessels. Persons with giant-cell arteritis also can have pain and stiffness in the shoulders and hips (polymyalgia rheumatica). Doctors first suspect giant-cell arteritis from the patient's symptoms and from examination of the forehead vessels. The vessels may be tender to the touch and have weak or even absent pulsations. Before starting treatment (with steroid drugs), doctors sometimes perform a biopsy of forehead vessels to confirm the presence of inflammation and abnormal arteries. Color duplex ultrasonographic scans may be less painful than a biopsy for confirming giant-cell arteritis. These scans look at vessel walls and blood flow by using short pulses of sound waves that are transmitted from a device placed on the surface of the skin. The scans sometimes detect dark halos around inflamed vessels. The halos seem to indicate swelling in the vessel wall. Although scans sound like a good idea, we do not really know whether they are any better than a careful clinical examination for detecting giant-cell arteritis.