What Causes Bulging Eyes?

Having remarkably protruding eyes disrupts people's appearance and vision. Bulging of the eyes, also known as exophthalmos, can have significant health implications.

The most common cause of exophthalmos is an autoimmune disorder that produces inflammation in the orbit, the area surrounding the eye. Thyroid eye disease most often occurs in a subset of people who have Graves' disease, which involves an overactive thyroid gland, or hyperthyroidism. Less frequently, thyroid eye disease is associated with an underactive thyroid gland, or hypothyroidism.

Distorted vision, light sensitivity, excessively dry eyes, pain and loss of balance are complications of thyroid eye disease. Surgery -- usually more than one -- is the ultimate treatment for people with severely protruding eyes.

However, an investigational drug with promising study results may potentially offer future patients with thyroid eye disease a nonsurgical alternative to treat protruding eyes.

[See: 10 Signs Your Thyroid is Out of Whack.]

Drastic Eye Changes

Ron Barela looked in the mirror one day and what he saw was shocking. "My right eye was twisted completely to the left as far as it could go," he says. "My left eye was twisted to the right." That was about 25 years ago, and his eyesight hasn't been the same since.

Barela, then about 50, remembers feeling "incredibly dizzy," and somewhat nauseated, with blurred vision. Until that moment, his eyes were always perfectly normal. But with the sudden change, he says, "I looked like the old actor Marty Feldman."

For Feldman, having protruding, skewed eyes in some ways worked to his advantage in his film career. Not so for Barela, then an officer in the Berkeley Police Department in California.

"The major problem it created was that I had no real horizon," Barela says. "I kept losing my vision and would stagger, sway and occasionally fall. And that is not good for a policeman, to be falling down in public."

[See: 10 Seemingly Innocent Symptoms You Shouldn't Ignore.]

Evaluating Eye Protrusion

In thyroid eye disease, the autoimmune system attacks the soft tissues and muscles surrounding the eyes, which may lead to bulging. Before making a diagnosis, doctors must rule out other conditions.

When a single eye is protruding, there may be a tumor behind or around the eye pushing it forward and making it bulge. An infection of the eyelid, called cellulitis, could spread to the eye socket if left untreated. A thorough evaluation pinpoints the cause.

"Thyroid eye disease is virtually always bilateral disease," says Dr. Roger Dailey, a professor of ophthalmology at Oregon Health & Science University and a clinician with OHSU's Casey Eye Institute. Although both eyes are usually involved, the extent and appearance can be quite asymmetric, he explains. One eye may protrude first, with the other eye showing changes at a later time.

"Once you have a diagnosis, it depends on where (patients) are in the course of their disease," Dailey says. "If they're fairly early on and quite inflamed, you might consider some anti-inflammatory treatment, specifically oral steroids."

However, long-existing eye protrusion is different. "If they've had it for years and there's no inflammation, just the physical findings, you might start moving toward surgical correction," Dailey says.

As part of the decision-making process, Dailey asks patients to bring in old pictures to assess how their eyes have changed.

"There are obvious situations that require treatment, such as the eye spontaneously popping out of the socket in front of the eyelid -- not a pleasant experience," Dailey says. "That needs to be taken care of. Or the front of their eyes touching the back of their glasses -- that's not a tenable situation long-term."

Some people just get mild eye disease. "It may be worse for a while then get better and mostly go away and they may not need any treatment or any surgery," Dailey says. "So there's a whole spectrum of disease severity."

In moderate-to-severe cases, a patient's quality of life is worsened. "It's just about impossible to function," Dailey says. "(Patients) get significant dry eye because of exposure to the air. And it's very light-sensitive, so they want to be in a dark room, wear sunglasses, use drops all the time. And then you throw in some very disorienting double vision."

Treatment for Thyroid Eye Disease

Some symptoms of thyroid eye disease may eventually go away on their own, while others persist. The Casey Eye Institute website describes related treatments in depth. Here's a brief look at thyroid eye disease complications:

-- Eye dryness and irritation can result. Applying artificial tears frequently can help, as well as using a lubricant gel at night.

-- Double vision can occur as eye muscles are affected and possibly scarred. Double vision may disappear on its own, or may require surgical correction once stabilized.

-- Retracted eyelids can also result from scar tissue in eyelid muscles. With less coverage from the eyelid, more of the white of the eye shows above and below the iris, the colored portion of the eye. Eyelid retraction can also lead to dryness, tearing, irritation and light sensitivity. Eye repositioning procedures, such as surgery of the upper eyelid and grafts for the lower eyelid, can improve eye sensation and appearance.

-- Eye protrusion occurs when fluid collects in the muscles and fat surrounding and behind the eye. If protrusion doesn't resolve after a period of months, orbital decompression surgery to remove some bone and fat can normalize eye appearance and relieve pressure and discomfort.

-- Vision loss can occur for several reasons. Depending on the cause, oral medications may restore normal vision. In some cases, surgery or radiation may be needed.

Cosmetic surgery is an also an option to correct appearance-related issues such as eyelid swelling or bagging, the Casey Eye Institute website notes.

Trying to Adjust

Barela, who was immediately seen at the hospital when his eye troubles started, underwent various medical tests. Once diagnosed, his thyroid condition only took several weeks to get under control. "But the damage it did to my eye muscles and such continued on," he says. "For the better part of two years, I was legally blind."

Barela's police department made adjustments to help him. "I'd be driven to work, and people would give me little things I could do and see," he says. "I had a number of magnifying glasses and I learned quickly to just use one eye at a time."

He sometimes felt self-conscious and he experienced social ramifications. "Many of my close friends have been fellow officers, who were afraid to talk with me about it or joke with me because they didn't want to hurt my feelings," Barela says. "But that strained a few relationships." Some acquaintances were concerned that his eye condition might be contagious. (It isn't.)

Eventually, Barela underwent a series of surgeries to correct his vision, improve his appearance and restore his quality of life. "I was able to resume my career in law enforcement and drive a car," he says. "I could shoot a gun as accurately as I ever could."

[See: 14 Ways to Protect Seniors From Falls.]

Treatment Breakthrough?

Before modern treatments, people with protruding eyes could suffer indefinitely. "It's only in the last several decades that the surgical techniques have been developed to help these patients," says Dr. Terry Smith, a professor of ophthalmology and visual sciences and of internal medicine at the University of Michigan Medical School. "But now we think there's potential to make many -- not all -- but many of these surgeries unnecessary."

In 2016, an investigational, intravenous drug called teprotumumab was designated as a breakthrough therapy for thyroid eye disease by the Food and Drug Administration. Teprotumumab, which is a member of the drug class called monoclonal antibodies, is showing promise in clinical trials.

A study published May 4, 2017, in the New England Journal of Medicine randomly assigned 42 patients with active thyroid eye disease to receive teprotumumab and 45 other patients to receive a placebo. Within six weeks, 43 percent of the treatment group, compared to 2 percent of the placebo group, had reduced eye protrusion. Dailey is among the study co-authors.

The study was led by Smith, whose early laboratory research while he was at UCLA developed the rationale to use the drug for this condition. The initial discoveries were published from 2002 to 2008, says Smith, who holds patents related to that work.

Last week, results were announced from a later, Phase 3 clinical trial. Of participants with active thyroid eye disease, nearly 83 percent responded with meaningful reduction in eye bulging after receiving teprotumumab for 24 weeks, according to a Feb. 29 news release from Horizon Pharma.

Between 15,000 and 20,000 people in the U.S. are affected by thyroid eye disease each year, according to the Horizon release.

"Around 50 percent of patients who develop Graves' disease actually develop the eye disease," says Smith, who is also the chief medical and scientific officer of the Graves' Disease and Thyroid Foundation. "Of those, maybe 10 to 20 percent will have severe enough eye disease that they need to come to surgery."

The latest findings bring teprotumumab a step closer to FDA approval. "This new drug will potentially change the paradigm of how patients with this disease are treated," Smith says. "We're very excited that, for the first time, we may have a medical therapy that will not only improve the inflammation around the eyes, but may lessen the severity and change the outcome of the disease."

Moving On With Thyroid Eye Disease

After Barela left the police force, he and his wife moved to Washington to run a bison ranch. He took due caution around the animals to avoid falls and resulting dizziness. Now retired, the couple travels, mostly on ships, where the motion doesn't bother him much.

Barela's vision is not completely restored. "When I walk down a narrow hallway, I need to drag one hand along a wall so I don't start leaning and then fall," he says. "If I go up and down stairs, variations in lighting can cause me to get dizzy. Patterns in carpeting can do that, too. But being aware of those things, I can plan and think ahead. I refuse to let it get me down."