Benign thyroid swelling presenting as Horner's syndrome.

Horner's syndrome is a rare neurological condition seen in association with the disruption in the sympathetic nerve supply. Thyroid swelling is a common condition but rarely causes cervical sympathetic chain compression. We describe a case of a 54-year-old man who presented with Horner's syndrome secondary to a benign thyroid nodule with pressure effect on the sympathetic chain. An association between thyroid pathologies and Horner's syndrome has been mentioned previously, however, to our knowledge, this is the first case of Horner's syndrome being the initial presentation for an underlying benign thyroid swelling.