Your eyes have gotten super dry and irritated, and it hurts to move them. Or they’re red, watery, and swollen. Maybe you’ve been dealing with all of the above. You may have noticed your eyes look like they’re bulging more than before. In recent photos, you always seem to look startled. Maybe you’ve even had blurred or double vision. You know it isn’t allergies, but you can’t figure out what’s going on.
It’s possible that you have thyroid eye disease. And if you have an autoimmune thyroid disease, especially Graves’ disease, this is even more likely. That’s because around 90% of thyroid eye disease cases are seen in people with Graves’ disease, explains Christian Nasr, MD, an endocrinologist and medical director of the Thyroid Center at Cleveland Clinic.
What Is Thyroid Eye Disease?
Thyroid eye disease (TED) is a rare autoimmune disease that affects the eyes. TED causes swelling, inflammation, and damage in the muscles and tissues around the eyes. “The majority of cases are mild,” says Raymond Douglas, MD, PhD, an oculoplastic and orbital surgeon practicing in Beverly Hills and director of the Thyroid Eye Disease Program at Cedars-Sinai in Los Angeles.
Symptoms can vary, but they include:
- Redness
- Dryness
- Discomfort
- Pain behind your eyes
- Irritation
- Eyelid retraction (when your eyelid doesn’t close all the way)
- Bulging eyes
- Feeling like there’s something in your eye
- Blurry vision
- Double vision
- Bloodshot eyes
- Eyelid swelling
- Constant watering of the eye
- Headaches
- Eye socket pressure or pain
Who Gets TED?
TED usually happens in people who have Graves’ disease. Graves’ disease causes your thyroid to make too much thyroid hormone, a condition called hyperthyroidism. “About half of patients with Graves’ disease will develop thyroid eye disease,” Nasr says. He adds that most cases of TED happen within a year to 18 months of developing Graves’ disease.
About 80% of people who come in with TED have already been diagnosed with Graves’ disease, Douglas says. Around 10% are diagnosed with TED before Graves’. Another 5% of TED cases are in people with Hashimoto disease, Nasr says. In this condition, your thyroid doesn’t make enough thyroid hormone, a condition known as hypothyroidism. Though it’s rare, Douglas says some people with TED don’t have a thyroid condition at all.
Thyroid eye disease is more common in women than in men. But when men develop TED, it tends to be more severe. Douglas says cases of TED peak around ages 40-50 and again around age 60.
What Is the Link Between TED and Hyperthyroidism?
Three conditions can cause hyperthyroidism. One is Graves’ disease, the most common one. The others are thyroid nodules and toxic multinodular goiters. “Graves’ disease is the only condition where you can see thyroid eye disease associated with high levels of thyroid hormone,” Nasr says.
Both thyroid eye disease and hyperthyroidism are immune system disorders. “From what we know, there are two receptors that seem to be the culprit,” Douglas says. One is the thyrotropin (TSH) receptor, which is mostly on thyroid cells. The other is the insulin-like growth factor (IGF-1) receptor, found mostly on the cells around the eyes. These two receptors sit next to each other, he says, and appear to be linked.
Experts don’t understand why, but the immune system starts to attack these receptors. When it attacks the TSH receptor, this causes too much thyroid hormone. “It’s like turning up the thermostat way too high,” Douglas says. When the immune system attacks the IGF-1 receptor, it increases the amount of IGF-1. The cells around the eyes get fat, divide, and accumulate extra scar tissue, causing thyroid eye disease.
If you have Graves’ disease, certain things can make your risk of developing thyroid eye disease higher. These include:
- Having a family history of TED
- Smoking
- Being female
- Getting radioactive iodine treatment
- Older age
- Stress
- Poorly controlled thyroid
What Are the Complications of TED?
TED can affect the two most important parts of the eye: the cornea and the optic nerve. “We make sure that both of these are monitored,” Nasr says.
Some of the possible complications TED can cause include:
- Bulging eyes
- Pain
- Scratched cornea
- Extreme dryness
- Severe headaches
- Trouble blinking
- Eyelids not closing completely
- Restricted eye movement
- Double vision
- Increased pressure in the eyes
- Blindness (rare)
Nasr tells his patients to call immediately if they see a dark spot in their vision field or multiple bright lights off and on. This might indicate optic nerve damage.
He says it’s also important to call right away if you have severe pain or severe redness around your iris (the colored part of your eye). This could mean your cornea is damaged.
Who Treats TED?
Both doctors say treating thyroid eye disease involves an integrative approach. Experts on your care team may include:
- Endocrinologists
- Ophthalmologists
- Oculoplastic surgeons
- Neuro-ophthalmologists
“It’s really a team approach between primarily endocrinologists and oculoplastic surgeons,” Douglas says. Many people start with their ophthalmologist to figure out what’s going on. “Then, depending on the severity, they’ll be sent to someone like me, an oculoplastic surgeon, who will then talk to them about medical therapies versus surgical therapies,” he says.
Many general ophthalmologists are comfortable monitoring mild TED, too, Nasr says. They can keep track of your eye pressure, check your corneas, and do tests to make sure your optic nerve is in good shape.
Nasr also works with neuro-ophthalmologists to monitor the optic nerve. “Once in a while, we use strabismus specialists to work on correcting muscles to minimize double vision,” he says.
What Should I Do If I Think I Have TED?
Plenty of people chalk up their eye issues to aging or allergies, Douglas says. And even when they try to find out what’s wrong, they may be told it’s just allergies. If you notice your eyes bulging, vision changes, or your eyelids aren’t closing all the way, Douglas advises seeing your doctor. “Don’t just settle for an unsatisfactory answer,” he says.
Nasr makes a point of asking all his patients who have autoimmune thyroid disease if their eyes are dry, uncomfortable, or if they have pain behind them. “Dry eyes are probably the most common symptom in patients who have thyroid eye disease,” he says. But since dryness can be subtle, it can go unnoticed.
If you already have thyroid disease, you should be seeing an endocrinologist anyway. They will continue doing what they do best — keeping your thyroid well-controlled. Nasr does a thorough eye exam every year. He uses a special instrument to measure how much the eyeball is protruding. Your endocrinologist can refer you to another expert for treatment if needed, too.
Maybe you don’t have a history of thyroid disease. In this case, your best option is to see an ophthalmologist. They will be able to diagnose TED. You’ll also need to have your thyroid levels checked by your primary doctor or an endocrinologist. This is because chances are high that you also have undiagnosed Graves’ disease.
It’s rare, but you may have TED with normal thyroid hormone levels. But even if they’re normal, you’ll need to have your levels checked regularly over the next year or two. This is because you could develop Graves’ disease during that time.
