Horner syndrome following thyroid surgery: the clinical and pharmacological presentations

Purpose: to report the clinical and pharmacological findings of a patient with iatrogenic horner syndrome (hs) which occurred after thyroid surgery. case report: a 29-year-old man was referred to our emergency ward due to anisocoria and unilateral eyelid ptosis reported by the patient immediately after a recent thyroidectomy for a papillary carcinoma. ophthalmologic examination revealed 3 mm ptosis of the right eyelid. in dim illumination,the right and left pupil size was measured 3 and 6 mm,respectively. in bright illumination,the amount of anisocoria decreased; the near pupillary reaction was intact. brain and neck magnetic resonance imaging and chest radiography were normal. pharmacological tests with 10% cocaine,1% hydroxyamphetamine and 1% phenylephrine localized the interruption of the oculosympathetic pathway with postganglionic third-order neuron involvement. after 6 months of follow-up,no sign of recovery was recorded. conclusion: despite hs could appear to be a rare complication of thyroid surgery,it is of importance for the neck surgeons to be aware that oculosympathetic pathway (osp) is a potentially vulnerable structure with close anatomical relationship with the thyroid gland,and for the ophthalmologists that hs may occur secondary to neck surgery and taking an accurate history is mandatory. © 2016 journal of ophthalmic and vision research.