superior laryngeal nerve
A branch of the vagus nerve with external and internal divisions. The external branch innervates the cricothyroid muscle and is at risk during thyroid surgery.
Full Definition
The superior laryngeal nerve is a branch of the vagus nerve that divides into external and internal branches. The external branch of the superior laryngeal nerve (EBSLN) provides motor innervation to the cricothyroid muscle, which is responsible for vocal cord tensioning and pitch control. During thyroid surgery, particularly when dissecting near the superior thyroid pole, this nerve is vulnerable to injury. Damage results in loss of vocal pitch control and voice fatigue, particularly affecting singers and professional voice users.
Usage
Usage note: Distinguish clearly from recurrent laryngeal nerve in surgical documentation.
In Context
- "Care was taken to identify and preserve the external branch of the superior laryngeal nerve during superior pole dissection." — Operative report
- "The patient experienced voice fatigue consistent with superior laryngeal nerve injury." — Post-operative note