Graves Eye Disease: Causes, Symptoms, Treatment and Prognosis

Graves eye disease, also called Graves' ophthalmopathy, is an autoimmune condition in which the immune system attacks the muscles and other tissues around the eyes. It is linked to Graves' disease, the most common cause of an overactive thyroid.

The thyroid is a small, butterfly-shaped gland in the front of the neck. It makes thyroid hormones (T4, or thyroxine, and T3) that control how the body uses energy. Too little hormone is called hypothyroidism; too much is hyperthyroidism, or thyrotoxicosis.

Graves eye disease and other thyroid eye diseases are not caused by high thyroid hormone itself. The same immune reaction drives both, and eye disease can even occur when thyroid levels are normal.

Swelling behind the eye can push the eyeballs forward (proptosis) and pull the eyelids back, giving a staring look. Exposed eyes dry out, which can lead to corneal ulcers. In severe cases, swollen eye muscles limit and hurt eye movement. Rarely, swelling presses on the optic nerve and threatens vision, which needs urgent care.

Causes of Graves Eye Disease

In Graves' disease, the immune system makes an antibody called thyroid-stimulating immunoglobulin (TSI). It acts like the hormone TSH and pushes the thyroid to make too much hormone, causing a fast or irregular heartbeat, weight loss, shaky hands, sweating and nervousness.

More than 1 in 3 people with Graves' disease develop eye disease. Smoking raises the risk and makes it worse.

Eye symptoms come from inflammation and swelling of the muscles and fatty tissue behind the eye. This swelling pushes the eye forward, causing the bulging look of Graves' eye disease, along with limited and painful eye movements.

Symptoms of Graves Eye Disease

Symptoms can start before, at the same time as, or rarely after thyroid symptoms. Most people have mild disease.

Early Symptoms

Gritty, irritated or watery eyes, light sensitivity, puffy eyelids, redness, eye pressure, and bulging eyes

Late Symptoms

Double or blurred vision, painful or limited eye movements, corneal ulcers, and rarely loss of vision

Investigations and Diagnosis

Following investigations are done to diagnose the disease.

1- Thyroid Function tests

Blood tests measure TSH, T4 and T3, and can check for TSI antibodies.

2- Imaging

A CT scan or MRI of the eye sockets can show swollen eye muscles. A Doppler ultrasound of the thyroid may be used when radioactive tests aren't suitable.

3- Thyroid scan

A radioactive iodine uptake test and thyroid scan show how actively the thyroid takes up iodine.

4- Eye Checkup

An ophthalmologist does a full eye exam, including vision, eye pressure, eye movement and how far the eyes protrude.

Treatment Options for Graves Eye Disease

1- General Measures

Most mild cases can be managed with simple steps. Use lubricating eye drops (artificial tears) for dry, gritty eyes. Wear sunglasses for light sensitivity. Cool compresses may ease swelling, and sleeping with your head raised can reduce puffiness.

If your eyelids don't close fully, taping them or wearing an eye mask at night can prevent dryness. Glasses with prisms can help with double vision.

If you smoke, quitting is one of the most important steps. Have regular eye checkups to catch progression of the eye disease, and keep thyroid hormone levels well controlled.

Too much iodine, from kelp, seaweed or iodine supplements, can worsen hyperthyroidism. Ask your doctor which foods and supplements to limit.

2- Medication

Antithyroid drugs such as methimazole control the overactive thyroid. For moderate to severe eye disease, doctors may prescribe steroids, often given by IV, or other medicines that calm the immune response. Some eye doctors suggest a short course of selenium for mild cases; take it only on their advice.

3- Radioiodine and Radiation Therapy

Despite what some sources claim, chemotherapy is not used for Graves' disease. The overactive thyroid is often treated with radioactive iodine, but this can worsen eye disease, so tell your doctor about any eye symptoms first. Radiation therapy aimed at the tissues around the eyes is used rarely.

4- Surgery

Surgery can relieve pressure behind the eye, correct double vision or reposition the eyelids, usually once the disease is stable. Sometimes the thyroid gland itself is surgically removed to treat hyperthyroidism.

Prognosis

The outlook is generally good. Most cases are mild, and eye disease often improves with treatment or settles on its own, though it can flare again. Stress and smoking are known triggers. See an eye doctor promptly if your vision changes.

Sources

• Graves' Disease, NIDDK
• Graves Disease, MedlinePlus