Giant cell arteritis, also known as temporal arteritis is a vasculitis of the medium and large arteries, particularly those in the head. It is characterized by a biopsy result showing giant cells - a union of several different types of cells of the immune system.
The disease has no known cause and is currently theorized to be a type of autoimmune disorder. Although it can affect arteries anywhere in the body, it tends to have more of an effect on those in the head. As a result, the muscles controling the eyes, tongue and jaw are the most likely to be affected and show symptoms.
Once giant cell arteritis is suspected, steroids should be administered, followed by confirmation by biopsy. At the beginning, high doses are required, but the patient can be tapered off to a level where the disease is managed. Steroids can be administered orally unless vision loss has resulted, in which case intravenous steroids are indicated.