Diagnosis of Graves' Ophthalmopathy
Diagnosis of Graves' is based on clinical signs and symptoms, as well as tests to determine the extent and severity of the disease. Patients exhibiting symptoms of GO are examined and assessed for Graves' disease with a thyroid function test. The eye disease is treated by an ophthalmologist.
After a comprehensive eye examination, the eye care practitioner may also check for exophthalmos proptosis (forward displacement of the eye), which leads to incomplete lid closure, exposure of the cornea while blinking or sleeping, and irritation. A CT scan or ultrasound is performed to determine if the muscles around the eye are swollen and to detect fibrosis (hardening of muscle tissue). Fibrotic tissue can permanently reduce some degree of range of eye movement.
The specialist measures how far the eye protrudes with an exophthalmometer, a small instrument that resembles a ruler. The patient faces the doctor and the exophthalmometer is positioned to measure how far the eye protrudes beyond the rim of the eye socket. This measurement helps assess the degree of tissue swelling and muscle enlargement behind the eye.
Treatment for Graves' Ophthalmopathy
Treatment of Graves' ophthalmopathy is aimed at relieving symptoms, which usually results in decreased intraocular pressure (IOP) and reduced risk for glaucoma and possible blindness.
Patients with GO who have hyperthyroidism are treated with anti-thyroid drugs, radioactive iodine (may carry a slight risk for making eye symptoms worse), or surgery to reduce the production of thyroid hormone. The selection of a particular modality depends on the patient's age and preference, and the severity of the illness. Eye symptoms may improve, but sometimes GO continues to progress.
Ointments or artificial tears and cool compresses can relieve dryness and irritation. If the eyelids cannot completely close, the eyes may be taped shut at night to help the patient sleep and to avoid dryness. Sleeping with the head of the bed elevated can alleviate swelling. Wearing sunglasses protects the eyes from sun and wind and prism sunglasses can help correct double vision (diplopia).
Nonsteroidal antiinflammatory drugs (e.g., ibuprofen) and oral corticosteroids (e.g., prednisone) are used to reduce inflammation and swelling. Corticosteroids also suppress the immune system, which can slow or stop the progression of the autoimmune response that is causing the symptoms of GO.
Chronic treatment with oral corticosteroids can produce a number of side effects, however, including the following:
- Behavioral changes (extreme mood swings)
- Decreased carbohydrate tolerance
- Impaired wound healing
- Muscle wasting
- Peptic ulcer
Increased intraocular pressure is common with chronic corticosteroid treatment, so the effects of this medication must be closely monitored when it is used to treat GO.
Cessation of smoking may reduce symptoms and enhance treatment.
A surgical procedure called orbital decompression may be performed when:
- proptosis has led to corneal exposure and risk for corneal ulceration;
- there is severe orbital discomfort; or
- there is compression of the optic nerve.
This involves removing bone tissue from the eye socket to create more space for the eye and enlarged muscle tissue. Surgery also may be performed on the eye muscles to realign the eyes and correct double vision in the straight-ahead gaze. The patient may continue to have double vision in other directions (left, right, up, down). Oculoplastic surgery may be performed on the eyelids to enable the eyes to close completely and to minimize protrusion of the eyes.
Surgeries are performed in the following order and never at the same time:
- Orbital decompression
- Eye muscles
- Eyelid repair
A waiting period follows each procedure. If the problem is alleviated, further surgical treatment may be unnecessary.
There is no known way of preventing Graves' disease or Graves' ophthalmopathy. Not smoking may decrease the incidence.