What is thyroid eye disease?
Thyroid eye disease (TED), also called Graves' eye disease, is an autoimmune condition in which the body's immune system mistakenly attacks the muscles and soft tissue inside and behind the eye socket. This causes inflammation, swelling, and expansion of the orbital tissues, which can push the eye forward, pull the eyelids out of their normal position, and affect how the eye moves and functions.
Thyroid eye disease most commonly occurs in people with Graves' disease, a condition that causes the thyroid gland to become overactive. However, it can also develop in people with an underactive thyroid or even normal thyroid function. Treating the thyroid condition itself does not resolve the eye involvement. Thyroid eye disease requires its own separate evaluation and treatment.
Thyroid eye disease progresses through two distinct phases, active and inactive phases. During the active phase, the immune system is actively attacking the orbital tissue, causing ongoing inflammation, swelling, and worsening symptoms. This phase typically lasts between six months and two years, though it can last longer, particularly in people who smoke. Treatment during the active phase focuses on protecting the eyes, managing inflammation, and slowing the progression of damage.
During the inactive phase, the inflammation has stabilized and the disease is no longer actively worsening. Some symptoms, such as redness and eye pain, may improve. However, structural changes including bulging eyes, eyelid retraction, and double vision often remain. Surgical treatment to correct these changes is typically performed during the inactive phase, once the disease has been stable for a period of time.
What are the symptoms of thyroid eye disease?
Symptoms vary depending on the severity of the disease and which phase it is in. Common symptoms include:
- Bulging or protruding eyes, known as proptosis
- Eyelid retraction, in which the upper eyelid sits higher than normal or the lower eyelid sits lower, making the eyes appear wide or staring
- Dry, gritty, or irritated eyes
- Excessive tearing
- Redness of the eyes or eyelids
- Swelling or puffiness around the eyes
- Double vision
- Difficulty moving the eyes in certain directions
- Pain or pressure behind the eyes, particularly with eye movement
- Sensitivity to light
- Blurred or decreased vision
In severe cases, the optic nerve can become compressed by the swollen orbital tissue, which can threaten vision. Any sudden change in vision associated with thyroid eye disease should be evaluated by a healthcare provider.
What causes thyroid eye disease?
Thyroid eye disease is an autoimmune condition. The same antibodies that affect the thyroid gland can also bind to the tissue behind the eyes, triggering an immune response that causes the muscles and fatty tissue within the orbit to swell and expand. As the volume of tissue inside the eye socket increases, the eye is pushed forward and the eyelids can be pulled out of position.
How is thyroid eye disease diagnosed?
Diagnosing thyroid eye disease begins with a thorough evaluation by an oculofacial plastic surgeon, often in coordination with an endocrinologist managing the underlying thyroid condition. During this evaluation, your surgeon will:
- Review your symptoms, their timeline, and your thyroid history
- Assess the degree of eye bulging, eyelid position, and eye movement
- Evaluate vision and examine the health of the cornea and optic nerve
- Assess disease activity to determine whether the condition is in the active or inactive phase
Imaging studies are typically ordered to evaluate the extent of orbital involvement. These include a CT scan, which provides detailed images of the bony orbit and the size of the affected muscles and fat. An MRI scan provides more detailed imaging of the soft tissue structures within the orbit and can help assess the degree of active inflammation
Blood tests to evaluate thyroid function and thyroid-related antibodies are also an important part of the workup.
How is thyroid eye disease treated?
Treatment depends on the phase of the disease, the severity of symptoms, and whether vision is at risk. Because thyroid eye disease affects both the thyroid and the eyes, care is typically coordinated between an oculofacial plastic surgeon and an endocrinologist.
Supportive care is recommended for all patients with thyroid eye disease, regardless of severity. Lubricating eye drops and ointments help protect the cornea from dryness and irritation caused by eyelid retraction and incomplete blinking. Wearing sunglasses can reduce light sensitivity, and elevating the head of the bed at night can help reduce morning swelling. Smoking cessation is strongly recommended, as smoking worsens disease severity and can reduce the effectiveness of treatment.
Anti-inflammatory medications may be used during the active phase to reduce orbital swelling and slow disease progression.
If conservative treatment does not improve TED, orbital decompression surgery may be recommended. This procedure involves carefully removing bone and fat from the eye socket to create more space, allowing the eye to move back into a more natural position. It is used to reduce significant eye bulging, relieve pressure on the optic nerve when vision is at risk, and improve the ability of the eyelids to close over the eye. Orbital decompression is typically performed during the inactive phase of the disease, after inflammation has stabilized, though it may be performed earlier in cases where vision is threatened.
Eyelid surgery addresses eyelid retraction, the wide or staring appearance caused by the upper eyelid sitting too high or the lower eyelid sitting too low. Surgical procedures to lower the upper eyelid or raise the lower eyelid can restore a more natural eyelid position, improve the ability of the eyes to close fully, and reduce dryness and corneal exposure. Eyelid surgery is typically the final step in the surgical rehabilitation of thyroid eye disease.
Thyroid eye disease is a complex condition that changes over time and requires care at every stage. The oculofacial plastic surgeons at The Iowa Clinic evaluate and treat the full spectrum of thyroid eye disease, from early supportive management through surgical rehabilitation. Call 515.875.9480 to schedule an appointment.