| Pyriform sinus | |
|---|---|
 Pyriform sinus, a part of hypopharynx | |
 The entrance to the larynx, viewed from behind, with Pyriform sinus labeled at bottom left. | |
| Details | |
| Identifiers | |
| Latin | recessus piriformis, sinus piriformis |
| MeSH | D056144 |
| TA98 | A05.3.01.024 |
| TA2 | 2880 |
| FMA | 55067 |
| Anatomical terminology | |
The pyriform sinus (also piriform recess, piriform sinus, piriform fossa, or smuggler's fossa) is a small recess on either side of the laryngeal inlet. It is bounded medially by the aryepiglottic fold, and laterally by the thyroid cartilage and thyrohyoid membrane.[1] The fossae are involved in speech.
The term "pyriform," which means "pear-shaped," is also sometimes spelled "piriform".[citation needed]
The term smuggler's fossa comes from its use for smuggling of small items.[2]
Deep to the mucous membrane of the pyriform fossa lie the recurrent laryngeal nerve as well as the internal laryngeal nerve, a branch of the superior laryngeal nerve.[3] The internal laryngeal nerve supplies sensation to the area, and it may become damaged if the mucous membrane is inadvertently punctured. The pyriform sinus is a subsite of the hypopharynx. This distinction is important for head and neck cancer staging and treatment.[4]
This sinus is a common place for food particles to become trapped; if foreign material becomes lodged in the piriform fossa of an infant, it may be retrieved nonsurgically. If the area is injured (e.g., by a fish bone), it can give the sensation of food stuck in the subject's throat.[2]
Remnants of the pharyngeal pouches III and IV may extent to the piriform sinus as sinus tracts which are sometimes imprecisely called "fistulas".[5][6] This can result in acute infectious thyroiditis which is more common on the left side of the neck.[7]
This article incorporates text in the public domain from page 1142 of the 20th edition of Gray's Anatomy (1918)
{{cite book}}: CS1 maint: location missing publisher (link)
