EDITORIAL: Thyroid associated orbitopathy: Understanding pathophysiology

Thyroid-associated orbitopathy (TAO) or thyroid eye disease is the most common cause of unilateral or bilateral proptosis in adults. The disease is more prevalent in female patients than male counterparts with annual incidence being 16/100,000 in women and 3/100,000 in men (Stiebel-Kalish et al., 2009; Yang et al., 2011). When males are affected, they tend to have a later onset and a poor prognosis. Other poor prognostic indicators include, age greater than 50 years, rapid onset of symptoms under 3 months, cigarette smoking, diabetes, severe or uncontrolled hyperthyroidism, pretibial myxedema, hyperlipidemia and peripheral vascular disease (Stiebel-Kalish et al., 2009; Yang et al., 2011; Stan and Bahn, 2010).