Thyroid Eye Disease: Causes, Symptoms, Treatments

An autoimmune disorder is a health condition in which the body's immune system mistakenly attacks it.

The immune system is essential for the body to safeguard against disease-causing bacteria and viruses.

Usually, the body's immune system can quickly identify between foreign and own cells. However, in the autoimmune condition, the system mistakes body parts such as skin and joints as foreign and releases specific proteins called antibodies to attack the healthy cells.

One such autoimmune disease is Graves disease (also known as thyroid eye disease) affecting the eyes, skin, and thyroid.

The exact prevalence of this disease is still unknown and it is considered a rare disease in the medical world.

Studies have shown that 2.9 per 100,000 males in the general population and 16 per 100,000 females in the general population are affected by thyroid eye disease.

This is an autoimmune condition in which the immune system causes swelling and inflammation in the eye. It also causes the production of fat and muscle tissue behind the eye.

Also known as Graves’ ophthalmology or Graves’ eye disease, this is a condition in which the body's immune system produces antibodies that activate receptors in the thyroid gland.

This then results in too much thyroid hormone in the body. In addition, the immune system's response against the thyroid gland can affect the eye, causing thyroid eye disease.

This will cause the eyelids and the eyes to become swollen, red, and bulging out.

It also causes swelling and stiffness of the eye muscles, making it difficult to move in a line resulting in double vision.

Thyroid eye disease, also commonly known as TED, is often associated with hyperthyroidism and takes up about 90% of the cases.

While the disease is a result of malfunctioning of the thyroid gland, TED is also sometimes seen in people who have no evidence of thyroid dysfunction. Additionally, it may also happen to people who have Hashimoto's disease.

Most thyroid patients won't generally develop this disease, and even if they do so, the symptoms are mild. However, if you are a regular smoker, you might experience more severe symptoms.

As it is an autoimmune condition, anyone can develop this disorder. Let us look at some of the risk factors that increase the likelihood of contracting this disease.

• Women are more susceptible to developing Graves disease.
• Having a family history of this condition.
• Increased use of tobacco can affect the body's immune system, thus increasing the risk of TED.
• TED usually develops in people who are below the age of 40.
• Recent childbirth or pregnancy among women who have an ancestral history of TED.
• People with genetic conditions such as Rheumatoid Arthritis or Type 1 Diabetes have a higher risk of getting this disease.

The initial symptoms of thyroid eye disease include irritation, redness and discomfort of eyelids and eyes. In some instances, sweat will form around the eyes.

Symptoms can appear as early as six months. These may include:

• Dryness in the front region of the eyes.
• Difficulty in moving the eyes.
• Redness and swelling of the eyes.
• Light sensitivity.
• Redness and swelling of the eyes.
• Blurred vision and colours may appear in the early stages.
• Double vision or diplopia due to the excessive swelling of eye muscles.
• Irritation and redness in the eyes due to lack of lubrication.
• Pain at the back of the eyes, which is worse in the morning while looking down, sideways or up.
• Bulging of the eyes and the person will start to have a startling appearance often known as exophthalmos.

Thyroid eye disease may cause secondary glaucoma and leads to blindness.

If you notice any symptoms mentioned above, it is best to have an immediate eye examination to avoid any long-term eye damage.

If you are already diagnosed with thyroid hormone issues, the doctor may want to conduct a periodic physical examination to check for any signs of TED.

If he suspects the presence of the disease, he may conduct further tests such as:

• MRI/CT Scan : It is done to scan the eye muscles. This will help to identify the most affected tissue.
• Blood tests : This test will help determine the thyroid gland's functioning efficiency by measuring its hormone in the bloodstream.
• Doctors will carry out additional tests to assess the vision, such as checking the peripheral vision, asking to identify colours and eye movement tests to check if any muscle has been affected. These tests are periodically done to assess the disease.

There are two main stages of thyroid eye disease. They are:

Active or acute phase : This stage is marked by inflammation of the eyes and may last for six months to two years. The symptoms may suddenly worsen over time.

Inactive phase : As the name suggests, the inactive phase occurs when other symptoms and inflammation have subsided. It does not mean that the disease will not appear again. Thyroid eye disease is an ongoing condition and requires prompt medical attention.

There are two stages of thyroid eye disease treatment.

The initial or the active phase is the stage when the disease should be monitored carefully. The treatment methods will be primarily focused on treating double vision, preserving eyesight and integrity of the cornea.

If the eyes get too dry, artificial tear drops are used during the daytime and gels and ointments are used at night.

Immunosuppressants are prescribed to slow down the immune system producing abnormalities.

In the second phase, surgery is often advised to reduce eyelid retraction and correct double vision.

The eyelids can be returned to a normal position within the socket with surgery.

To prevent TED from getting worse, one can follow the following measures.

• Quit smoking.
• Ensure that your body doesn't experience any thyroid fluctuations. Get regular blood tests to check for thyroid hormone levels and take the prescribed medications regularly.
• Avoid radioiodine treatment if you are a smoker and have TED.
• Supplement your body with selenium. Studies have shown that patients with mild TED experiences benefit from selenium supplements if taken over six months.

If you experience any symptoms mentioned in this article, make sure to seek immediate medical attention.

Learn about the various treatment options and Ophthalmology services available at Gleneagles Hospitals, Malaysia.

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