Thyroid eye disease (TED) is an autoimmune condition in which the tissues of the eye socket (orbit) are attacked by the same antibodies that attack and dyregulate the thyroid gland.
About 90% of patients who develop thyroid eye disease also have Graves disease, or hyperthyroidism. This results in an excess of thyroid hormones causing symptoms such as a rapid or racing heart rate, sweating/heat intolerance, weight loss, irritability, and hair loss or thinning. Only about 50% of people who have Graves disease will develop TED.
The remaining 10% of those with TED have Hashimoto’s disease, primary hypothyroidism or euthyroid, meaning the thyroid gland and hormones function normally but they have the antibodies present that attack the orbital tissues.
Thyroid eye disease can range from mild to severe disease. The antibodies cause the eyelid and orbital tissues to inflame. The eye muscles and fat in the eye socket can enlarge. Symptoms include: eye bulging, pain in the orbit, pain with eye movement, double vision, eyelid retraction, swelling of the eyelids, redness of the eyelids, swelling of the eyes (called chemosis), redness of the eyes, dryness in the eyes, light sensitivity, tearing of the eyes. In the most severe cases, vision loss can occur but this only occurs in 10% or less of cases.
Thyroid eye disease is highly variable depending on the patient, and treatment must be tailored to the patient.