The Superior Laryngeal Nerve

Abstract

The superior laryngeal nerve, once an afterthought in thyroid surgery, is now recognized as a vital structure worthy of preservation in thyroidectomy. The superior laryngeal nerve is a branch of the vagus nerve which bifurcates into an internal branch, providing sensory innervation to the larynx, and an external branch, supplying motor innervation to the cricothyroid. The anatomical path of the internal branch of the superior laryngeal nerve protects it from injury during thyroidectomy. The external branch, however, can be closely associated with the superior pole of the thyroid, and as such can be at high risk of intraoperative injury. The surgical approach to preservation, direct identification versus avoidance, remains controversial. While current advancements in thyroid surgery, including minimally invasive and robotic thyroidectomy, have introduced new challenges in superior laryngeal nerve preservation, continued innovations in surgical strategies and nerve monitoring technology allow for consistent preservation of the external branch of the superior laryngeal nerve.