Which nerve provides sensation to the piriform recess?

From the Guidelines

The internal branch of the superior laryngeal nerve provides sensation to the piriform recess. This nerve is a branch of the vagus nerve (cranial nerve X) and supplies sensory innervation to the laryngeal mucosa above the level of the vocal folds, including the piriform recesses, as described in the study by 1. The piriform recesses are paired structures located on either side of the laryngeal inlet, forming part of the hypopharynx. This sensory innervation is clinically significant because foreign bodies can lodge in the piriform recess and stimulate this nerve, triggering protective reflexes such as coughing or gagging. Additionally, when performing procedures such as flexible laryngoscopy or during intubation, stimulation of this area can provoke these protective reflexes, as noted in the context of thyroid surgery and the importance of preserving the superior laryngeal nerve 1. Understanding this innervation is important for clinicians performing examinations of the hypopharynx or when administering topical anesthesia prior to certain procedures. Key points to consider include:

• The internal branch of the superior laryngeal nerve is responsible for sensation in the piriform recess.
• This nerve is a branch of the vagus nerve and plays a critical role in protective reflexes.
• Preserving this nerve is important during surgical procedures in the vicinity, such as thyroid surgery, to maintain voice quality and prevent complications, as emphasized by 1. The information from 1 regarding the relationship of recurrent laryngeal nerves and superior laryngeal nerves to the thyroid lobe and tracheoesophageal groove, while informative about the anatomy and potential variations, does not directly impact the identification of the nerve responsible for sensation in the piriform recess.

From the Research

Nerve Supply to the Piriform Recess

The piriform recess, a small recess on each side of the laryngeal entrance, receives its sensory innervation from a specific branch of the superior laryngeal nerve.

• The internal branch of the superior laryngeal nerve (ibSLN) is responsible for providing sensation to the mucosa of the larynx, including the piriform recess 2.
• The ibSLN courses through the thyrohyoid membrane and splits into superior, middle, and inferior rami, with the superior ramus distributing to the mucosa of the piriform recess 2.
• The anatomy of the internal superior laryngeal nerve is complex, with variations in its branching pattern, but it is generally divided into three divisions: superior, middle, and inferior 3.
• The superior division of the internal superior laryngeal nerve supplies the mucosa of the laryngeal surface of the epiglottis, while the middle and inferior divisions supply other areas of the larynx 3.
• The internal branch of the superior laryngeal nerve is at risk of injury during surgical procedures in the neck, and knowledge of its anatomy is crucial to avoid damage 4, 5.