Thyroid Disease
Thyroid Disease and the Eye
Dr. Ebroon's Other Services
Graves' disease, a condition in which the thyroid gland is hyperactive, is rarely a life-threatening condition. Although Graves' disease may develop at any age and in either sex, it most often affects women 20 to 60 years old.
The disease can affect the thyroid gland, eyes, and skin. Unfortunately, the cause of Graves' disease is unknown. Current research, however, suggests that a defect in the immune system may be the underlying cause of the disorder. Normally, the immune system uses antibodies (protein substances that the body makes) to help protect itself against viruses, bacteria, and foreign substances (antigens) that invade the body. In Graves' disease the immune system mistakenly attacks the thyroid gland, eyes, and skin of the lower legs causing the disease's symptoms.
The Thyroid Gland
The thyroid gland is a butterfly-shaped organ located just in front and on each side of the windpipe just above the breast bone. The gland releases chemical messengers called hormones into the blood. These hormones influence body processes such as:
Rate of metabolism
Body temperature
Muscle tone and vigor
Growth hormone secretions
Normally thyroid activity is directed by the pituitary gland. In Graves' disease the thyroid is instead driven by an antibody. This antibody triggers the thyroid to become overactive and produce more hormones than the body needs. Symptoms of this overactivity, called hyperthyroidism, may include:
Weight loss (although appetite increases)
Irritability
Changes in menstrual patterns
Lower heat tolerance
Irregular heartbeat or pounding of the heart
Dr. Ebroon may suggest one of three treatments for hyperthyroidism:
1. Anti-thyroid medications
These medications block the action of the thyroid hormones
2. Radioactive iodine
A solution containing radioactive iodine is drunk. The iodine collects in the thyroid gland destroying large amounts of thyroid tissue
3. Surgery
Removal of most of the thyroid gland
Following treatment, the thyroid often becomes underactive (hypothyroidism). This causes symptoms to subside. When the thyroid becomes underactive, Dr. Ebroon will prescribe a thyroid hormone to achieve an appropriate balance.
During the course of hyperthyroidism other organs undergo changes. These organs include the skin and eyes.
The Skin
Some people with Graves' disease suffer from an irritating skin condition. Skin over the shins appears red and swollen. The top of the feet also may be affected in this way. Dr. Ebroon may recommend creams or ointments to reduce the swelling and redness.
The Eyes
When Graves' disease affects the eyes, it is called Graves ' ophthalmopathy (opf-thal-mop-athy). Eyes may bulge or appear red and swollen. The space between the lids may widen. Excess tearing and discomfort may occur in either or both eyes. Patients may experience sensitivity to light, blurring or double vision, inflammation, or decreased movement.
In Graves ' ophthalmopathy the eyeball protrudes beyond its protective orbit because tissues behind the eye attract and hold water. When this happens the tissues and muscles swell causing the eyeball to move forward in the orbit. The front surface of the eye can dry out. Eye symptoms and hyperthyroidism symptoms typically appear within 18 months of each other.
Dr. Ebroon recommends treatment of Graves ' ophthalmopathy according to each person's symptoms. Sometimes combinations of the following procedures are used. Dr. Ebroon may recommend:
Cool compresses, sunglasses, eyedrops or raising your head at night
Medications or radiation to shrink tissues
Orbital decompression surgery
Prisms for your glasses
Eye muscle surgery, eyelid surgery, or both
Orbital Decompression Surgery
In orbital decompression surgery the bone between the orbit (eye socket) and the sinuses (air spaces next to the orbit) is removed. A successful procedure improves vision and provides room for the eye to slip back into the orbit's protection.
There are possible complications of the surgery, however. You may experience lip numbness for several months after the operation. Double vision may persist or it may develop anew after surgery. Leaking of cerebrospinal fluid (CSF) that surrounds and protects the brain is a rare complication of the surgery. Recovery from this surgery typically begins with a short hospital stay. Follow-up office visits are scheduled after discharge.
Prisms
Dr. Ebroon may prescribe prisms for your glasses to correct double vision. Prisms may be temporary (pasted on) or permanently ground into your lenses. However, prisms do not work for all people with double vision. Sometimes eye muscle surgery is a more effective treatment.
Eye Muscle Surgery
Double vision usually occurs because the eyes are out of alignment. Misalignment often is caused by one or more eye muscles that are too short or "tight" because of scar tissue from Graves ' ophthalmopathy. This scar tissue results from changes in the eye because of inflammation. The goal of eye muscle surgery is to achieve single vision when looking straight ahead and when reading. During eye muscle surgery the muscle is cut from its attachment to the eyeball and reattached further back. Usually eye muscle surgery does not require an overnight stay in the hospital. More than one operation is sometimes required. If orbital decompression and eye muscle surgery are to be done, the orbital decompression surgery is usually done first.
Eyelid Surgery
Graves ' ophthalmopathy generally causes the eyelids to open more widely. The front surface of the eyeball becomes exposed beyond the eyelids and causes discomfort and excessive tearing. Surgically repositioning the eyelids can reduce the irritation. If orbital decompression, eye muscle and eyelid surgery are required, the eyelid procedure is generally performed as the final procedure in the series.
Conclusion
Although Graves' disease may affect comfort, vision, or appearance, many of these problems can be treated successfully. Thorough discussions with Dr. Ebroon will help determine an appropriate treatment plan.
