laryngealnerven

The laryngeal nerves are a pair of nerves that originate from the vagus nerve and play a crucial role in controlling the muscles of the larynx, which is responsible for voice production and airway protection. There are two main laryngeal nerves: the superior laryngeal nerve and the recurrent laryngeal nerve.

The superior laryngeal nerve divides into two branches: an external branch that innervates the cricothyroid muscle, responsible for tensing the vocal cords and affecting pitch, and an internal branch that provides sensory innervation to the larynx above the vocal cords. Damage to the external branch can lead to a weak or hoarse voice, particularly affecting the ability to produce higher pitches.

The recurrent laryngeal nerve follows a longer and more circuitous path. In the neck, it ascends back towards the larynx, lying close to the thyroid gland. This nerve innervates most of the intrinsic muscles of the larynx, including those that abduct (open) and adduct (close) the vocal cords, as well as the thyroarytenoid muscle which alters vocal cord tension. Lesions to the recurrent laryngeal nerve can cause vocal cord paralysis, resulting in hoarseness, breathiness, or difficulty breathing, depending on whether one or both vocal cords are affected.

Due to their anatomical location, the laryngeal nerves are vulnerable to injury during surgery, particularly thyroidectomies and neck dissections. Careful identification and preservation of these nerves during surgical procedures are paramount to prevent voice dysfunction.