Temporal arteritis is a condition that causes inflammation of arteries—the blood vessels that carry oxygen-rich blood from the heart. The exact cause of temporal arteritis is unknown, but the inflammation appears to be a result of the immune system overreacting and attacking the body’s own tissues. It is more common among older patients and almost never occurs under the age of 55.
The “temporal artery” is the name of a specific artery located on each side of the head. In the condition known as temporal arteritis, there is inflammation of numerous blood vessels, but the temporal arteries are almost always affected. Inflammation of arteries causes reduced blood flow, which is why this disease can cause severe symptoms.
A new headache, tenderness of the scalp, muscle aches, weight loss, and fevers are characteristic symptoms of temporal arteritis. It is also common to experience aching or pain in the jaw muscles when chewing (called jaw “claudication”). Visual loss occurs in about 25% of patients with temporal arteritis. The episodes of blurred or darkened vision can be brief and temporary, and usually affect one eye. In some cases visual loss can be quite sudden and severe. Because temporal arteritis can quickly progress to cause severe, irreversible visual loss in both eyes, prompt medical attention is extremely important when this condition is suspected.
Inflammation of the arteries causes them to become narrowed and impairs their ability to supply oxygen-rich blood. The arteries that travel to the eye are especially vulnerable in patients with temporal arteritis. When the eye and optic nerve (the cable that carries visual information to the brain) go without oxygen, they can become permanently injured, causing loss of vision.
Your doctor will ask you about your symptoms and perform a thorough eye exam. The doctor will feel the pulse in your temporal arteries. Blood tests are performed, including a test called the erythrocyte sedimentation rate (ESR), which is abnormal when inflammation is present. Sometimes, a test called fluorescein angiography may be performed. During this test, pictures are taken of the blood vessels in the back of the eye after a special dye is injected into a vein in the arm. When your doctor suspects temporal arteritis, a very important test that is often performed is a temporal artery biopsy.
This is a simple procedure done in a doctor’s office. After a small injection of anesthesia, an incision is made just above the ear. A piece of the temporal artery (usually one or more centimeters) is then cut and removed. A pathologist carefully examines the tissue to look for evidence of inflammation and “giant cells.” This finding is the reason that temporal arteritis has another name—“Giant cell arteritis.”
When temporal arteritis is strongly suspected, a steroid medication called prednisone should be started very quickly. This is especially important when there have been symptoms of visual loss. Prednisone reduces inflammation in the affected arteries and many patients feel better in several days. In some cases, a patient will be admitted to the hospital to receive additional tests and treatments.
Patients taking prednisone should be monitored for side effects, which include osteoporosis, weight gain, high blood sugar, high blood pressure, changes in mood, muscle weakness, cataracts, glaucoma, and skin thinning. Most patients taking prednisone should take calcium and vitamin D supplements and many should take a medicine to prevent heartburn (gastritis).
Usually the visual loss that occurs due to temporal arteritis is permanent. The reason it is so important to make an early diagnosis and start treatment as soon as possible is to try to stop the inflammation before it progresses to cause severe visual loss in both eyes. Unfortunately, there are no known treatments to repair the optic nerve after it has been damaged.
It is common for patients with temporal arteritis to require prednisone for a year or more. Relatively high doses are typically required until the symptoms have resolved and the vision has become stable. Blood tests are repeated frequently to make sure it is safe to slowly lower the dose of the medications. If high doses of prednisone cause intolerable side effects, other medications can be used to help lower the dose of prednisone. These include medications that suppress the immune system such as methotrexate (Trexall®), azathioprine (Imuran®) and mycophenolate mofetil (CellCept®). Recently, a special, targeted immune-therapy called tocilizumab (Actemra®) has been approved for treatment of temporal arteritis.
We believe that patients benefit from online medical information that is engaging, up to date, and reliable. Philanthropic support is vital to produce these educational resources. To support these efforts, please click here.
For over a century, a leader in patient care, medical education and research, with expertise in virtually every specialty of medicine and surgery.