What Is Thyroid Eye Disease?
If you’ve been diagnosed with a thyroid condition like Graves’ disease or Hashimoto’s thyroiditis, your doctor may have advised you to be aware of thyroid eye disease (TED). With Graves’ disease and Hashimoto’s thyroiditis, your immune system malfunctions and attacks your thyroid gland; if you have Graves’ disease, that means your thyroid responds to this attack by overproducing thyroid hormone, leading to hyperthyroidism. If you have Hashimoto’s thyroiditis, your thyroid’s response to the attack is to underproduce thyroid hormone, leading to hypothyroidism. So what does this have to do with your eyes?
The tissues and muscle surrounding your eyes contain proteins that are very similar to the proteins mistakenly targeted by your immune system in your thyroid. Experts theorize this is why people with thyroid dysfunction sometimes develop inflammation around the eyes–what we call thyroid eye disease. Although physicians used to believe thyroid eye disease only affected people with overactive thyroid, new data shows its presence in some people with underactive thyroid. About 85% of people with thyroid eye disease have hyperthyroidism, 10% have hypothyroidism, and 5% appear to have normal functioning thyroid glands. Because of its initial connection with Graves’ disease, you may hear thyroid eye disease referred to as Graves’ eye disease or Graves’ ophthalmopathy.
Signs and Symptoms of Thyroid Eye Disease
The symptoms of thyroid eye disease are usually mild and easily treatable, but they do need to be addressed. Eyelid retraction, when the eyelid doesn’t close properly, is the most common sign, occurring in 90% of those diagnosed with the condition. The second most common symptom is bulging eyes (exophthalmos), experienced by 60% of patients, and restricted eye movement, affecting 40% of patients. Other signs and symptoms include:
- Dry eyes
- Watering or tearing
- Light sensitivity
- Inability to blink (staring)
- Pain when moving eyes
- Droopy lid when looking down
In some cases, more serious problems can develop; the two most severe complications are optic neuropathy, when swelling compresses the optic nerve, and corneal ulcers (exposure keratopathy), which are painful, destructive changes that occur in the eyes due to inadequate eyelid closure. Both can lead to vision loss, although this is relatively rare with thyroid eye disease.
Most people who have thyroid eye disease also have underlying hyperthyroidism, usually Graves’ disease. More women than men develop it, and smoking increases the risk up to eight-fold.
To determine whether you have thyroid eye disease, your doctor will likely perform visual tests, take measurements of your eyelids and eye pressure, and order magnetic resonance imaging (MRI).
Thyroid Eye Disease Treatment
For some people, thyroid eye disease symptoms clear up on their own. If they don’t, your primary care provider will likely work with a team of specialists on your treatment plan, including:
Initial treatments will depend on your specific symptoms, but they usually include eye lubricants, cold compresses, elevating your head while sleeping, or eyeglasses with tinted lenses or prisms. Prisms are special lenses that reduce double vision by redirecting light before it reaches your eyes.
If symptoms persist, your doctor may recommend a selenium supplement; selenium is an antioxidant that’s crucial in helping the thyroid function. You may also be prescribed oral corticosteroids, with or without radiation therapy, to help reduce swelling, or antithyroid drugs or radioactive iodine to slow down your thyroid. Immunotherapy is a new treatment option currently in clinical trials, and it will likely be approved by the U.S. Food and Drug Administration (FDA) soon. This type of drug works directly with the immune system to correct its faulty attacks.
Surgery to move the eyelid or muscles around the eye may be considered in time. It’s usually not performed within one to three years of a thyroid eye disease diagnosis because doctors prefer to try less invasive options first. Orbital decompression surgery, which opens up more space around the eye, is usually only performed when there is a threat of vision loss.
Remember, for most people who have thyroid eye disease, extreme steps aren’t necessary. Don’t let fear delay relief. Talk with your doctor if you experience any signs or symptoms.