Thyroid Eye Disease
What is Thyroid Eye Disease?
Thyroid eye disease, also known as Graves’ ophthalmopathy or Graves’ orbitopathy, is an autoimmune condition that primarily affects the tissues and muscles around the eyes. It is most commonly associated with an overactive thyroid gland (hyperthyroidism), particularly in individuals with Graves’ disease, an autoimmune disorder that affects the thyroid.
Thyroid eye disease (TED, Graves’ eye disease, Graves’ ophthalmopathy) may occur in the absence of known thyroid disease, or may precede thyroid disease.
Thyroid eye disease is sometimes associated with an over-active thyroid (hyperthyroidism) due to Graves’ disease. Graves’ disease is an autoimmune condition that leads to the production of antibodies which stimulate thyroid cells to produce excess thyroid hormone. Some people with Graves’ disease may also have Hashimoto’s thyroid disease, which is associated with antibodies which reduce thyroid hormone production.
So, strangely, one may have Graves’ disease and yet have an underactive, normally active, or overactive thyroid hormone production. Autoimmune thyroid disease is associated with, but not the direct cause of Thyroid Eye Disease, wherein antibodies are produced which target some of the fibroblasts in eye muscles or orbital connective tissue within the eye socket. Inflammation causes swelling and/or scarring that may push the eye forward resulting in a bulging appearance. The presenting symptom of TED may be eyelid puffiness, pain, redness, tearing, blurred vision, double vision, eyelid retraction or bulging eyes; the presentation may be unilateral or asymmetric.
Patients who have been newly diagnosed with thyroid eye disease should seek evaluation by their family physician, internist or endocrinologist to assess and treat any underlying thyroid gland disorder. It is not the thyroid hormone which causes TED, but rather the associated autoimmune reaction. So, while it is of critical importance to one’s health and well-being to have thyroid function monitored and treated, doing so will not prevent or stop TED.
Symptoms of Thyroid Eye Disease
- Change in the appearance of the eyes (usually staring or bulging eyes)
- A feeling of grittiness in the eyes
- Dry or watery eyes
- Dislike of bright lights
- Swelling or feeling of fullness in one or both upper eyelids
- Bags under the eyes
- Redness of the lids and eyes
- Blurred or double vision
- Pain in or behind the eye, especially when looking up, down or sideways
- Difficulty moving the eyes
Several tests are conducted to assess vision and changes in the tissues around the eyes. These may include vision testing, visual fields assessment, eyelid measurements, sensorimotor evaluation, eye pressure readings, fundus and external photography, optical coherence tomography and orbital ultrasonography.
In mild cases when there is a feeling of grittiness in the eyes, tearing or sensitivity to light, artificial tear drops may be recommended. Cool compresses, sunglasses, or prisms for glasses may also help relieve symptoms. Patients can sleep with their heads elevated to help reduce eyelid swelling, and it is often recommended to apply a nighttime gel or ointment to the eyes. Symptoms may take as long as a year to improve and up to three years for the inflammation to resolve.
In more severe instances, treatment options include corticosteroids or other anti-inflammatory medications, radiation, and surgery, alone or in combination.
In the most severe cases, emergency treatment (often surgical) may be needed to prevent permanent damage to the optic nerves.
Even when vision loss is not likely, permanent damage may occur due to thyroid eye disease resulting in changes in eye position, eye muscles or eyelids, with consequent problems of chronic ocular irritation and pain, double vision and/or impaired blink or eyelid closure. Appearance of the eyes may also continue to be altered. Surgical options may help improve vision, the health of the eyes and appearance.
Rehabilitative surgery may include:
- Decompression surgery to create space behind the eyes and relieve orbital pressure resulting in improved vision and comfort. This surgery involves the removal of excess fat and/or the bone between the orbit and the sinuses providing room for the eye to revert back to a more normal position.
- Eye muscle surgery to treat double vision. Our specialists offer surgical options to adjust the muscles around the eye to align vision in both eyes. In Graves’ disease patients, diplopia (double vision) often occurs because of eye misalignment. One or more eye muscles become too tight because of scar tissue that forms within the muscle. Eye muscle surgery to relieve the tightness may achieve single vision when looking straight ahead and looking down when reading. The eye muscle is cut from its attachment to the eyeball and re-attached further back on the eye. In many cases more than one operation may be required. If both orbital decompression and eye muscle surgery are recommended, orbital decompression is generally performed prior to the eye muscle surgery.
- Eyelid surgery to reposition the eyelid improves the function and appearance of the eyelids.