Exophthalmos

What is exophthalmos?

Exophthalmos is a bulging forward of one or both eyes. In some cases, the eyelids can no longer cover the entire front of the eye.

How does it occur?

Exophthalmos occurs when the soft tissue lining the eye socket swells. This can happen with a type of thyroid disease called Graves' disease, which is the most common cause of exophthalmos.

A tumor or abnormal blood vessels behind the eye could also push the eye forward.

A bacterial infection in the eye socket (orbit), called orbital cellulitis, may also cause the eye to bulge. If not treated quickly and properly, this infection can spread from the eye socket to the brain. It may cause permanent loss of sight and can be life threatening.

What are the symptoms?

The symptoms include:

• eyeball bulging forward, exposing more of the sclera (the white of the eye) than is normal (you appear to stare all the time)
• limited eye movement
• blurred vision
• double vision
• gritty, dry feeling in eye
• eyelids may be forced open and in severe cases cannot be closed completely.

How is it diagnosed?

The doctor will do a complete eye exam. The doctor may also measure how far your eye is bulging forward with an instrument called an exophthalmometer.

The doctor may also want you to have these tests:

• a blood test to check thyroid hormone levels
• an ultrasound test or a computerized scan (CT or MRI) of your eye sockets, to look for a tumor or other possible reasons for your eye to be pushed forward.

How is it treated?

The treatment of exophthalmos depends on the cause.

If the cause is thyroid disease, your doctor may suggest that you:

• Take anti-thyroid or steroid drugs.
• Have an operation on your thyroid gland, which cures about 90% of the cases (although you may have to take hormone supplements).
• Use a radioactive iodine drink to destroy most of the thyroid tissue.

If the exophthalmos persists or is caused by other disorders, your doctor may suggest one of the following:

• Have surgery to relieve the pressure that is responsible for the bulging eye or to help the eyelids close.
• Take antibiotics for infections.
• Have surgery to remove a tumor, if present. Removal of the eye may be necessary in severe cases.
• Have radiation therapy.
• Use steroids to decrease swelling behind the eye.
• Use eyedrops or ointment to keep the eye moistened.
• Wear prism glasses or have surgery on your eye muscles to correct double vision.
• Wear eye patches at night if the eyes don't close completely.

Eyelid surgery can be done to reduce the staring look and improve your appearance, regardless of the cause of your problem. This type of surgery is done only after other necessary eye bone or muscle surgery has been done.

How long will the effects last?

If thyroid disease is the cause and you are treated early, your vision and appearance may return to normal. However, in some cases, even after thyroid disease has been successfully treated, the bulging will not go away and may even worsen.

The effects may be long-term or permanent in very serious cases that are not treated early enough or are affected by other illnesses.

How can I take care of myself?

Follow any instructions the doctor has given you, including taking any prescribed medicine. Make sure you take all the medication you are prescribed, even if you start to feel better.

How can I prevent exophthalmos?

There is no proven way to prevent any of the causes of exophthalmos.

Tell your doctor if you notice any of these symptoms of thyroid disease:

• nervousness
• sleeplessness
• always feel warm or cold
• eating more, yet losing weight
• fast or irregular heartbeat
• blurring of your vision or double vision
• a bulging forward of one or both eyes
• irritation or swelling of your eyes.

Regular health checkups and eye exams can help in early discovery and treatment.