Updated December 15, 2014.
What Is Graves' Disease?
Graves' disease is the most common form of hyperthyroidism. Graves' disease is a condition in which the body’s immune system attacks the thyroid gland -- the gland that helps set the body's rate of metabolism. This attack causes the thyroid gland to enlarge and produce high levels of thyroid hormones, often much more than the body needs. The excessive amounts of hormone can cause tissue changes and many unpleasant side effects such as weight loss, rapid heart rate and nervousness.Although it is not proven, some doctors feel that Graves' disease is set off by a stressful event in a person’s life.
Symptoms of Graves' Disease
Although Graves' disease can cause the following symptoms, the condition doesn't usually produce any long-term adverse health problems as long as prompt treatment is received.- Fatigue
- Weight loss
- Restlessness
- Decrease in menstrual cycle
- Rapid heartbeat
- Frequent bowel movements
- Sex drive changes
- Muscle weakness
- Tremors
- Heart palpitations
- Increased sweating
- Nervousness
- Irritability
- Heat intolerance
- Thinning or drying out of the hair
- Blurred or double vision
- Eye irritation
- Difficulty sleeping
- Increased appetite
How Does Graves' Disease Affect the Eyes?
Graves' disease sometimes causes inflammation and swelling in the soft tissues and muscles that surround the eyes, often causing the eyeballs to bulge or protrude from their sockets. Known as exophthalmos, or proptosis, bulging of the eyeballs is a distinguishing symptom of Graves' disease. Exophthalmos often causes the eyes to feel achy, dry and irritated, as the eyelids become unable to perform their duty of sheltering the eyes from injury.Diagnosis of Graves' Disease
Doctors will complete a physical exam by looking at the eyes for signs of irritation or signs of the eyes protruding.They will also examine the thyroid gland to see if it appears enlarged. Since many Graves' disease patients have an overactive thyroid or hyperthyroidism, diagnosis of the disease is also made based off of blood tests that look for specific thyroid-related hormones. Radioactive iodine scans may also be ordered to aid in the diagnosis of Graves' disease.
In a small number of Graves' disease patients, the thyroid and its circulating hormones are found to be normal, yet they develop all of the signs of thyroid disease. This is called euthyroid Graves' disease.
Graves' Disease Treatment
Treating Graves' Disease is centered on controlling the signs and symptoms of the disease, as it is very difficult for a doctor to stop the immune system from producing antibodies that cause Graves' disease. Medications are also given to reduce the amount of thyroid hormones that the thyroid produces. Radioactive iodine treatment is a method used to shrink the thyroid gland. Depending on the patient, surgery may also be required to remove the thyroid gland altogether. Patients may need additional medication afterward to ensure normal amounts of thyroid hormone.Because the eyes may be protruding, the eyelids may not close all of the way during sleep or normal blinking, causing irritation. To minimize eye irritation, artificial tears may be used several times per day and ointments may be applied at night to prevent the eyes from drying out. Steriods, such as prednisone, may be given to reduce swelling behind the eyes.
If the eyes are protruding to a great degree, a surgeon may perform orbital decompression surgery. This procedure involves removing the thin bones that make up the orbit of the eye so that the eyes may move back to a more normal position. This is also important because pressure inside the eye can increase if a considerable amount of pressure builds up around the eye, raising the risk of developing glaucoma.
Eye muscle surgery may be performed if needed, and eyeglass prisms may be prescribed if the eye muscles are so swollen that the eyes can no longer be aligned properly.
Source: Bartlett, Jimmy D. and Siret Jaanus. "Clinical Ocular Pharmacology," Chapter 27: Thyriod-Related Eye Disease, pages 699-724. Butterworth-Heinemann, 1989.