Thyroid Eye Disease
The thyroid gland is located in the front part of the neck. Despite the gland’s location, thyroid disorders can cause far-reaching problems throughout the body including thyroid eye disease. Changes in the eyes (Graves’ orbitopathy or Graves’ ophthalmopathy) can be a result and are specifically associated with Graves’ disease, a thyroid disorder. It is currently unknown exactly why changes in the eyes and eye sockets occur in association with Graves’ disease.
However, since the immune system is known to be compromised with the disease, it makes sense that swelling and inflammation in the eye muscles and other areas around the eye would occur – since the immune system is important for reducing inflammation.
Graves’ Eye Disease
The eye changes seen with Graves’ disease – infiltrative exophthalmos – may be explained by postulating that the thyroid gland and the extraocular muscles share a common antigen. Antibodies binding to the extraocular muscles, retroorbital muscles, retroorbital fat (see picture) would cause swelling behind the eyeball.
This swelling may also be due to mucopolysacharide deposits behind the eyes, a symptom related to Graves’ disease. Also, the “orange peel” skin seen in people with Graves’ has been explained by the infiltration of antibodies under the skin, causing an inflammatory reaction and subsequent fibrous plaques.
Thyroid eye disease symptoms
If you have thyroid problems, you can begin an effective treatment plan by scheduling an appointment with a Sydney ENT doctor — ear, nose and throat doctor. Chances are that you will not be affected by thyroid eye disease even if you are experiencing thyroid symptoms. However, if you are experiencing mild eye problems, effective management may be as simple as wearing protective eye covers at night and keeping your eyes lubricated with eye drops.
Individuals with thyroid eye disease may also benefit from wearing polarizing sunglasses and keeping their homes humidity levels up with a humidifier. For temporary relief from redness, swelling, and pain, steroid medications may help. If the problem worsens or does not improve, surgery is usually required. Swollen eyes can cause the cornea to continually be dry and irritated. Appearance of the eyes is also a concern for many people with the disorder.
Corrective eyelid surgery will return the eyelids as close to their normal position as possible so that these problems are alleviated. Other types of surgical procedures including orbital decompression endoscopic sinus surgery are often used to improve vision and relieve eye pressure. These types of thyroid surgery procedures typically are performed under general anaesthesia and require an overnight stay in the hospital.
Thyroid eye disease management
The eye changes (Graves’ orbitopathy) associated with Graves’ disease have significant consequences for the affected patient. The eye symptoms usually occur at the same time as the thyroid disease, however they may precede or follow the obvious symptoms of the thyroid abnormality. Most patients with thyroid abnormalities will never be affected by eye disease and some patients only mildly. Although the incidence of eye disease associated with thyroid dysfunction is higher and more severe in smokers, there is no way to predict which thyroid patients will be affected.
In addition, while eye disease may be brought on by thyroid dysfunction, successful treatment of the underlying thyroid disorder does not guarantee that the eye disease will improve as well, and no particular thyroid treatment can guarantee that the eyes will not continue to deteriorate. Once inflamed, the eye disease may remain active for years, so treatment may be needed.
Thyroid eye problems – Medical management
Early eye symptoms are usually mild, and may include dryness, redness, itching, swelling of the lids and inability to wear contact lenses. Some patients find these symptoms to be particularly irritating at night and under certain conditions such as air conditioning, hot air heating and windy days. Occasionally double vision (diplopia) will develop, which is the result of asymmetric scarring and inflammation of the muscles that control eye movement. Since most patients develop mild symptoms, thyroid eye disease is often misdiagnosed. So people with Graves’ disease should be followed by an ophthalmologist familiar with the condition and available treatments.
Patients with mild symptoms can often be successfully treated with frequent application of lubricating eye drops and wearing eye covers at night. Humidification of room air can prevent drying of the eyes, and wrap-around polarizing sunglasses can also help relieve glare. Prednisone, a steroid medication, may be taken orally to provide temporary relief from pain, swelling and redness, although side effects may limit the use of prednisone and related drugs. Vision loss due to pressure on the optic nerve is the most severe form of the disease – fortunately, this is rare, affecting less than 5% of patients with Graves’ orbitopathy.
Thyroid eye problems – Surgical management
Surgery is usually required if thyroid eye disease does not improve or deteriorates despite medical treatment. Retracted and puffy eyelids increase the risk of cornea drying and alter the appearance. Corrective eyelid surgery can alleviate the problem by placing the eyelids into a more normal position. Surgery may also be necessary to correct diplopia see with thyroid eye problems.
The enlargement of tissue behind the eye may sometimes cause significant forward protrusion of the eye (exophthalmos), which produces the characteristic appearance of thyroid eye disease, worsens the symptoms, and causes ocular exposure. Swelling in the orbit may actually contribute to vision loss as pressure increases on the optic nerve.
Surgical procedures to relieve pressure on the optic nerve improve vision and allow the eye to settle back to a more normal position. Orbital decompression is indicated in patients with significant exophthalmos, visual loss, or severe exposure of the corneas. These types of thyroid surgery procedures typically require the patient to stay overnight in the hospital and to undergo general anaesthesia.
If you have any questions about thyroid eye disease, you should speak to your local doctor, who will arrange to contact your ophthalmologist and thyroid surgeon.