Pharynx Anatomy Flashcards
General Features of Pharynx
A. The pharynx is a musculofascial tube serving respiratory and digestive functions.
B. Extends from base of the skull to CV6, where it is continuous with esophagus.
C. Connects oral and nasal cavities to larynx, for passage of air to and from lungs.
D. Connects oral cavity to the esophagus for passage of food/liquids to the stomach.
Divisions of the pharynx
- Nasopharynx – posterior to nasal cavities
- Oropharynx – posterior to oral cavity
- Laryngopharynx – posterior to larynx
Pharynx Communicates with 7 cavities:
- Nasal cavities (2) via choanae
- Tympanic cavities (2) via auditory (pharyngotympanic; Eustachian) tube
- Oral cavity
- Larynx
- Esophagus
Nasopharynx
- Pharyngeal recess – located on posterior superior wall of nasopharynx (anterior to CV1 and CV2)
- Pharyngeal tonsil
a. Located within pharyngeal recess - Tubal tonsil
a. Lymphoid tissue
b. Located near opening of auditory tube - Torus tubarius
a. Mucosal prominence formed by cartilage of auditory tube.
b. Pharyngeal ostium below torus tubarius represents opening of the auditory tube. - Salpingopharyngeal fold
a. Fold of mucosa overlying salpingopharyngeus muscle
b. Salpingopharyngeus muscle - Origin – cartilage of auditory tube
- Insertion – thyroid cartilage
- Innervation – vagus nerve
- Function – assists other pharyngeal muscles during swallowing
- Levator pad
a. Located below torus tubarius
b. Fold of mucosa overlying levator veli palatini muscle
CLINICAL CORRELATION: Adenoids
– enlarged, inflamed pharyngeal tonsils. Enlarged tonsils can obstruct nasopharynx, making breathing difficult. Infection can also spread to tubal tonsils; blocking the auditory tube and impairing hearing. Infections can also spread to middle ear (causing otitis media) via the auditory tube.
Oropharynx
Portion of pharynx posterior to oral cavity.
Fauces
passageway from mouth to oropharynx.
Faucial pillars
palatoglossal and palatopharyngeal folds.
Palatoglossal arch
a. Fold of mucosa overlying palatoglossus muscle
b. Palatoglossus muscle
1. Origin – soft palate
2. Insertion – tongue
3. Innervation – vagus n
- Function – pulls tongue and soft palate together during swallowing
Pharyngeal arch derived muscles always get
SVE fibers
Tonsillar bed/fossa
a. Depression between palatoglossal and palatopharyngeal folds
b. Structures forming tonsillar bed:
1. Superior constrictor
2. Hyoglossus
3. Middle constrictor
Palatine tonsil
a. Lymphoid tissue
b. Lies within tonsillar bed
Epiglottic valleculae
a. Depressions (2) between epiglottis and posterior tongue.
b. Formed by lateral and median glossoepiglottic folds.
Laryngopharynx
- Laryngeal inlet – anterior communication with larynx
- Piriform recess
a. Depression lateral to larynx
b. Internal laryngeal nerve runs deep to the mucosa of the piriform recess. - Narrows inferiorly to become continuous with the esophagus.
Clinical correlation: laryngopharynx (stuff gets stuck where and can damage what?)
Swallowed/inspired objects can sometimes lodge in the epiglottic valleculae or piriform recesses. If an object pierces the mucosa of the piriform recess it can potentially damage the internal laryngeal nerve.
macintosh blade
you will see the epiglottis. It is a curved blade.
Fascias of Pharynx
A. Pharyngobasilar fascia
- Internal
- Lines muscles of pharynx
B. Buccopharyngeal fascia
- External
- Covers muscles of pharynx
Muscles of pharynx: superior constrictor
- Circularly oriented muscle forming superior portion of pharynx
- Attaches to base of skull
- Innervation – vagus n via pharyngeal plexus
- Function – swallowing
Muscles of pharynx: middle constrictor
- Circularly oriented muscle forming middle portion of pharynx
- Attaches to hyoid bone
- Innervation – vagus n via pharyngeal plexus
- Function – swallowing
Inferior constrictor
- Circularly oriented muscle forming inferior portion of pharynx
- Attaches to thyroid and cricoid cartilages
- Innervation – vagus n via pharyngeal plexus
- Function – swallowing
Stylopharyngeus
- Origin – styloid process
- Insertion – thyroid cartilage
- Function – swallowing
- Innervation – CN IX
Salpingopharyngeus
- Origin – cartilage of auditory tube
- Insertion – thyroid cartilage
- Function – swallowing
- Innervation – CN X
Palatopharyngeus
- Origin – hard and soft palates
- Insertion – thyroid cartilage
- Function – swallowing
- Innervation – CN X
Gaps in Pharyngeal Wall
A. The overlapping pharyngeal constrictor muscles leave gaps in wall of pharynx; these gaps allow for passage of structures to and from the pharynx.
B. Gap 1
- Between base of skull and superior constrictor
- Allows for passage of levator veli palatini and auditory tube.
C. Gap 2
- Between superior and middle constrictors
- Allows for passage of stylopharyngeus and glossopharyngeal n
D. Gap 3
- Between middle and inferior constrictors
- Allows for passage of internal laryngeal nerve and superior laryngeal artery
E. Gap 4
- Between inferior constrictor muscle and esophagus
- Allows for passage of inferior (recurrent) laryngeal nerve and artery.
Vasculature of Pharynx
A. Arteries
- Superior thyroid artery
- Ascending pharyngeal artery
B. Veins
- Pharyngeal plexus of veins
- Drain to internal jugular vein
Pharyngeal Nerve Plexus
A. SVE
- Vagus n
- Except stylopharyngeus – glossopharyngeal nerve
B. GVA – Glossopharyngeal n.
C. Sympathetic fibers – directly from cervical sympathetic chain
Clinical Correlation – Gag Reflex (pharyngeal reflex
- Afferent limb – glossopharyngeal nerve
- Efferent limb – vagus nerve.
- Protective response to prevent foreign objects from passing deeper into pharynx or larynx. Stimulated by touching root of tongue, oropharynx.
Lymphatic Drainage of Pharynx
A. Retropharyngeal lymph nodes
B. Deep cervical lymph nodes
