Horner syndrome as a complication after thyroid microwave ablation: Case report and brief literature review

RATIONALE: Horner's syndrome (HS) can present as a complication of thyroid surgery, particularly after thyroid microwave ablation (MWA). HS presents clinically with eyelid ptosis, miosis, enophthalmos, anhidrosis, and vascular dilatation, all of which result from a damaged oculosympathetic chain. We aimed to try to avoid such devastating symptoms in future cases by exploring reasons for the destruction of the cervical sympathetic trunk. PATIENT CONCERNS: HS has previously been reported in the literature as a complication of thyroid surgery. Here, we report the case of a 44-year-old female patient who presented with miosis and eyelid ptosis following thyroid MWA. DIAGNOSES: This patient was subsequently diagnosed with HS. INTERVENTIONS: Mecobalamin was administered immediately. OUTCOMES: After 5 months of follow up, the patient's miosis and ptosis was incompletely relieved. LESSONS: Although HS is a rare complication of thyroid MWA, surgeons must be aware of the anatomic relationship of the cervical sympathetic trunk and thyroid gland with adjacent structures. Moreover, we hope this case presentation enables surgeons to take measures to minimize the possibility of oculosympathetic damage. Long-term follow up and comprehensive assessments are important for the patient's prognosis.