Encyclopedia - Graves' Disease

What causes this condition?
What are the symptoms?
How is it treated?

Graves' Disease was named in honor of the Irish physician, Robert Graves. He was the first to describe this form of hyperthyroidism, a thyroid disorder characterized by hyperactivity of the thyroid gland. Approximately 50 percent of people with Graves' disease develop eye symptoms, known as Graves' eye disease or Graves' ophthalmopathy. Eye symptoms are a result of a related autoimmune process, not a result of hyperthyroidism. The eye diseases and thyroid run independent courses, and both must be treated.

Graves' disease affects less than ¼ of 1 percent of the population and is more prevalent in women than in men. It usually occurs in middle age, but it can also affect children and adolescents. Although the disease is not curable, it can be controlled with proper treatment.

What causes this condition?

Graves' disease is caused by a generalized overactivity of the entire thyroid gland, and it represents a basic defect in the immune system, producing immunoglobulins (antibodies), which stimulate and attack the thyroid gland. This stimulation causes growth of the gland and overproduction of the thyroid hormone thyroxine. Similar antibodies may also attack eye tissue.

Increased blood levels of cortisone and adrenaline, which may be caused by severe stress, can affect antibody production by the immune system. However, this is not always the case as many patients who develop the disease have no identifiable stress present.

What are the symptoms?

Graves' disease is the only type of hyperthyroidism that is associated with inflammation of the eyes, swelling of the tissues around the eyes, and protrusion of the eyes. Although many patients with the disease experience eye irritation, less than 1 percent develop enough inflammation to cause permanent trouble. Once diagnosed, Graves' disease can be treated successfully.

The onset of Graves' disease is gradual, and the symptoms may be mistaken for simple nervousness because of stress. As the thyroid becomes overactive, pulse rate increases, often with sudden episodes of palpitations, increased sweating, and heat intolerance. Fatigue, weight loss, muscle weakness, enlarged thyroid gland, tremors, and irritability are other symptoms.

Eye symptoms are mild and easily treated. Excessive tearing, general feeling of eye irritation, light sensitivity, and double vision are all early symptoms. When tissues, muscles, and fat in the orbit behind the eye increase in volume, eye problems surface. The swelling associated with eye symptoms is what causes the proptosis or pop-eye look associated with Graves' disease. Swelling can cause paralysis of the muscles that move the eyeball or may compress the optic nerve. As eyelids and conjunctiva swell, they may retract, which can lead to corneal exposure and infection. (See Anatomy of the Eye.) Corneal ulceration and loss of vision may occur in severe cases.

How is it treated?

In the eye exam, the ophthalmologist will be looking for swelling behind the eye, eyelid retraction, and enlarged extraocular muscles. Cool compresses, artificial tears, and the use of sunglasses sometimes relieve symptoms of a mild case of Graves' eye disease. People with Graves' eye disease are often advised to elevate their heads while sleeping to alleviate swelling of the eyelids. Eyeglasses containing prisms are prescribed if double vision is a problem. In the early stages of Graves' disease, oral corticosteroids may help with muscle problems. However, later in the course of the disease, oral or IV steroids may be used to treat compression of the optic nerve, the most serious complication of the disease.

Radiation treatment is used when other treatments do not work. Orbital decompression surgery and other operations, such as extraocular muscle surgery to realign eyes and eyelid surgery to reposition the eyelids, are performed on patients with the most serious Graves' disease problems.