Differential diagnosis of thyroid orbitopathy — diseases mimicking the presentation or activity of thyroid orbitopathy

Abstract

with no previous or concomitant symptoms of thyroid disorders, lack of symptoms of eyelid retraction, divergent strabismus, diplopia as the only symptom of the disease, and a history of increasing diplopia at the end of the day.The inflammatory activity and severity of TO should be diagnosed based on personal experience and according to standard diagnostic criteria. Assessment of TO inflammatory activity can be performed using the clinical activity score (CAS). Magnetic resonance imaging (MRI) is not necessary to diagnose typical cases of TO but may be necessary to assess the inflammatory activity of TO, especially in those with a so-called "posterior" course. Orbital MRI is indicated in patients with unilateral or highly asymmetric exophthalmos, suspected optic nerve neuropathy, and TO with euthyroidism, while computed tomography (CT) of the orbit is par-