Abstract
OBJECTIVES: Horner syndrome (HS) is a rare complication of thyroid surgery. However, the relationship between the occurrence of HS and thyroid upper pole injury is still not completely clear, and there are only few reports. CASE PRESENTATION: A 24-year-old female underwent endoscopic thyroidectomy for thyroid papillary carcinoma. The intraoperative examination found that the upper pole of the thyroid was bleeding. During hemostasis, the ultrasonic knife consciously peeled too deep and stopped. The patient developed HS immediately after operation. We analyzed the association between deep dissection of the upper thyroid pole and an increase in the HS incidence rate through literature searches and anatomical relationships. CONCLUSIONS: Our case report discussed the potential relationship between the degree of thyroid upper pole dissection and the occurrence of HS in routine thyroid surgery, and provided a warning for the degree of thyroid upper pole dissection in the clinic to avoid HS.