![]() Middle and inferior pharyngeal constrictors.Squamous cell carcinoma of the hypopharynx most commonly develops in this region. ![]() Food particles can become trapped in these spaces.Piriform recess: a set of depressions in the hypopharynx located posterolaterally to both sides of the laryngeal opening.Inferiorly: esophagus at the level of the cricoid cartilage.Superiorly: upper margin of the epiglottis.Extends from the epiglottis to the beginning of the esophagus.Part of the conducting zone of the respiratory system.Inferiorly: upper margin of the epiglottis.Extends from the inferior border of the soft palate to the superior aspect of the epiglottis.Formed by the cartilaginous portion of the medial end of the eustachian tube.A mucosal prominence in the lateral aspect of the nasopharynx that protects the opening of the eustachian tube.Laterally: pharyngeal openings of the eustachian tube (connecting with the tympanic cavities), fossa of Rosenmueller, medial pterygoid plates, and superior pharyngeal constrictor muscles.Posteriorly: clivus, prevertebral musculature covering C1–C2.Extends from the base of the skull to the soft palate.Diseases that may affect the pharynx include infections ( pharyngitis, tonsillitis, diphtheria, infectious mononucleosis), sleep apnea, dysphagia, and pharyngeal cancer. The pharyngeal mucosa is lined by both stratified squamous epithelium and ciliated pseudostratified epithelium with goblet cells. Motor and sensory innervation are mainly via branches of the vagus and glossopharyngeal nerves. The lymphatics drain directly into the deep cervical nodes, either directly or through the retropharyngeal or paratracheal nodes. The pharyngeal veins drain into the internal jugular vein. The arterial supply is derived from branches of the external carotid artery, the ascending palatine and tonsillar branches of the facial artery, the maxillary artery, and the dorsal lingual branches of the lingual artery. The pharynx plays a role in deglutition, vocalization, and air conduction. from the uvula to the level of the hyoid bone), and the laryngopharynx (extending approx. from the base of the skull to the soft palate), the oropharynx (extending approx. It is divided into the nasopharynx (extending approx. Its development commences between the 4th and 7th week of gestation.The pharynx is a musculomembranous cavity that connects the oral and nasal cavities to the larynx and esophagus. Development Įmbryological origin is the third pharyngeal arch. Supernumerary muscles originating from other nearby regions of the skull may be present, and may be clinically significant. The glossopharyngeal nerve runs on the lateral side of this muscle, and crosses over it to reach the tongue. On the lateral pharyngeal wall, it is situated posterior to the superior constrictor muscle, and anterior to the buccopharyngeal fascia. The muscle is situated in between the external carotid artery and internal carotid artery. The stylopharyngeus is the medial-most and most vertical of the three styloid muscles. The lymphatic drainage of the region of the stylopharyngeus muscle is mediated by the middle cervical lymph nodes that drain into the supraclavicular lymph nodes. The stylopharyngeus receives arterial supply from the paryngeal branch of the ascending pharyngeal artery. ![]() The stylopharyngeus is the only muscle of the pharynx innervated by the glossopharyngeal nerve (CN IX) (all others being instead innervated by the vagus nerve (CN X)) by special visceral motor neurons with their cell bodies in the rostral part of the nucleus ambiguus. Some of its fibers are lost in the superior and middle constrictor muscles, some merge with the lateral glossoepiglottic fold, while still others join with those of the palatopharyngeus muscle to insert onto the posterior border of the thyroid cartilage. It is the only muscle of the pharynx not to originate in the pharyngeal wall. It arises from (the medial side of the base of) the temporal styloid process. It passes inferior-ward along the side of the pharynx between the superior pharyngeal constrictor (situated deep to the stylopharyngeus) and the middle pharyngeal constrictor (situated superficial to the stylopharyngeus), before spreads out beneath the mucous membrane. It is cylindrical superiorly, and flattened inferiorly. The stylopharyngeus is a long, slender, tapered pharyngeal muscle. It acts to elevate the larynx and pharynx, and dilate the pharynx, thus facilitating swallowing. It is innervated by the glossopharyngeal nerve (cranial nerve IX). Some of its fibres insert onto the thyroid cartilage, while others end by intermingling with proximal structures. It originates from the temporal styloid process. The stylopharyngeus muscle is a muscle in the head.
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