Superior Thyroid Artery

arteria thyroidea superior

The superior thyroid artery is the primary blood supply to the upper pole of the thyroid gland and the adjacent larynx through the superior laryngeal artery. It runs with the external branch of the superior laryngeal nerve (EBSLN) which supplies the cricothyroid muscle, and inadvertent ligation of the nerve alongside the artery during thyroid surgery produces the subtle but professionally devastating voice pitch limitation of EBSLN palsy.

Region: Neck

Anatomical Data

Origin, Insertion & Supply

Origin	First branch of the external carotid artery

Clinical Relevance

Clinical Notes

The external branch of the superior laryngeal nerve runs in close proximity to the superior thyroid artery — the nerve crosses the artery at variable distances from the superior pole (the Cernea classification), making identification and preservation of the nerve before ligating the artery the critical manoeuvre in upper thyroid pole dissection. Singers, teachers, and professional voice users are particularly affected by EBSLN injury.

Pathology

Common Injuries & Conditions

EBSLN Injury with STA Ligation

Cricothyroid muscle denervation from external SLN injury during superior thyroid artery ligation producing loss of high vocal pitch range, managed with voice therapy.