external branch of the superior laryngeal nerve
Motor nerve branch innervating the cricothyroid muscle, injury to which causes voice pitch and projection problems.
Full Definition
The external branch of the superior laryngeal nerve (EBSLN) is a motor nerve that innervates the cricothyroid muscle, which is responsible for vocal cord tensioning and pitch control. During thyroid surgery, this nerve is at risk of injury due to its variable anatomy and close relationship to the superior thyroid vessels. EBSLN injury results in inability to tense the vocal cords, leading to voice fatigue, loss of high pitch range, and reduced vocal projection. This complication is particularly devastating for professional voice users such as singers and teachers. Careful identification and preservation of this nerve during superior pole dissection is crucial for maintaining voice quality.
Usage
Usage note: Always spell out on first use, then may abbreviate as EBSLN.
In Context
- "Intraoperative neuromonitoring confirmed preservation of the external branch of the superior laryngeal nerve during superior pole dissection." — operative note
- "The patient's voice fatigue and loss of high pitch range suggested injury to the external branch of the superior laryngeal nerve." — otolaryngology consultation