Thyroid eye disease (TED) is a rare eye condition characterized by progressive inflammation
Thyroid eye disease (TED) is a rare eye condition characterized by progressive inflammation of and damage to the muscles and soft tissues in and around the eyes, especially the extraocular muscles (the muscles present in the orbit but outside the eyeball), connective, and fatty tissue. TED is also known as thyroid-associated ophthalmopathy (TAO), thyroid orbitopathy, Graves’ orbitopathy, or Graves’ ophthalmopathy (GO). The disease often appears suddenly with endocrine and ophthalmic symptoms impairing normal life. TED can cause facial disfigurement affecting the quality of life and daily function of patients.
Treatment of TED involves medications for controlling the symptoms; protecting the eyes; maintaining optimal thyroid hormone levels by using oral antithyroid medicine (methimazole and propylthiouracil), radioactive iodine, medications to suppress the immune system, and vitamin supplements such as selenium; and performing thyroidectomy (thyroid removal) and surgery to restore the function and appearance of the eyes (reconstructive orbital or eyelid surgery may be done).
Phases of thyroid eye disease
There are two phases of thyroid eye disease (TED):
- The active stage: It is the period in which progressive inflammation, swelling, and tissue changes occur, and this stage typically lasts for about 6 months to 2 years.
- The inactive or burnt-out stage: It is the stable phase when active inflammation settles down, and the disease progression stops. In some patients, the eyes return to normal, whereas in others, permanent changes such as double vision and bulging eyes may remain.
What causes thyroid eye disease?
Thyroid eye disease (TED) is caused by an autoimmune process in which the body sees part of itself as foreign and reacts to it as it would to any bacteria or viruses.
The immune system attacks both the thyroid and tissues around the eye. Although TED is seen in all thyroid disorders, it is more often associated with hyperthyroidism or Graves’ disease.
Patients with TED produce antibodies that bind to the fibroblast cells (a type of connective tissue making the cells) within the eye socket. This causes the fibroblast cells to produce chemical signals and release biological materials that lead to swelling and congestion in and around the eye socket. This causes inflammation and swelling of the fat and muscle tissues around the eye causing bulging of the eyes, retraction of the eyelids, and double vision.
What are the signs and symptoms of thyroid eye disease?
Some common signs and symptoms of thyroid eye disease (TED) include:
- Red and puffy eyelids that are more obvious in the morning
- Irritation and redness of the eyes
- Dry eyes (watering, grittiness, and soreness)
- Corneal scarring
- Bags under the eyes
- Eyelid retraction (the upper eyelid rises to a higher position making the white of the eye more visible causing staring eyes)
- Exophthalmos or proptosis (bulging of the eyes)
- Difficulty in closing eyelids
- Strabismus (also called squint)
- Swelling or feeling of fullness in one or both the upper eyelids
- Blurring or dimming of vision due to optic nerve compression
- Painful orbits (eye sockets)
- Pain in or behind the eye, especially when looking up, down, or sideways
- Difficulty moving the eyes
- Diplopia (double vision due to pain or restricted eye movements)
- Discomfort to bright lights
- Pressure sensation with headache