Thyroid eye disease (TED) most commonly occurs as part of Graves’ disease, where the immune system attacks the thyroid, typically causing hyperthyroidism or increased thyroid hormone production. In up to 50% of patients with Graves’ disease, inflammation can also affect the tissues around the eyes leading to thyroid eye disease (TED). It’s not clear why the eyes are affected, but immune cells that attack receptors around the eyes cause inflammation and tissue expansion. Specifically, the insulin like growth factor 1 receptor (IGF-1R) has been identified as playing a central role in the pathogenesis of TED and is the basis for targeted treatment of TED. Women are approximately 5-6 times more likely to experience TED than men. Smokers have a significantly increased risk for TED.
The disease is recognized to follow two general phases: an active phase where there may be ongoing inflammation and change, and a stable phase during which the inflammation has subsided and there is little day to day changes in appearance or symptoms. Thyroid eye disease can range from mild to severe, and symptoms can be variable from one individual to another. In the active phase, there is typically inflammation of tissue around the eye as well as tissue expansion. The tissues that typically expand include orbital fat and extraocular muscles. These changes can lead to a variety of clinical findings.
