Horner's syndrome subsequent to minimally invasive video-assisted thyroidectomy in two patients.

Horner's syndrome (HS), characterized by a combination of ptosis and miosis, is an uncommon complication of thyroid surgery, particularly in minimally invasive thyroid surgery. Two cases of HS were observed secondary to minimally invasive video-assisted thyroidectomy in the Department of Thyroid Breast Surgery of Zhejiang Provincial People's Hospital between August 2012 and July 2014. The two patients developed miosis and ptosis following total thyroidectomy; all symptoms had resolved at 1 and 11 months subsequent to surgery, respectively. HS has currently been reported secondary to numerous types of minimally invasive thyroid procedures. The literature was reviewed to identify cases of this iatrogenic complication secondary to each type of thyroidectomy and the possible injury mechanisms underlying the syndrome were summarized in the present study. In addition, factors that were associated with minimally invasive thyroidectomy, such as the limited endoscopic vision during the procedure, the retraction effect and the occurrence of thermal damage from the use of the harmonic scalpel, were emphasized. The present study concluded that close attention is required during minimally invasive thyroid surgery in order to avoid HS as a complication of the procedure.