G53: The Pharynx Flashcards
The pharynx connects the
nasal and oral cavities to the esophagus and larynx
Pharynx has complete _________ walls and incomplete ________ walls
posterior and lateral walls; anterior walls
Retropharyngeal space
space between buccopharyngeal fascia and prevertebral fascia
External layers of pharynx
buccopharyngeal fascia
Buccopharyngeal fascia
outer surface of buccinator, continuous with pretracheal fascia
Outer layer of muscle - Pharyngeal constrictors
outer layer of voluntary muscle, circular in orientation
Inner layer of muscle
stylopharyngeus and palatopharyngeus, longitudinal in orientation
Internal fibrous layer of pharynx
pharyngobasilar fascia, suspends pharynx from skull
Mucosa of pharynx
abundant mucosal glands and lymph tissue (esp in tonsils)
Nasopharynx
posterior to nasal cavity
choanae
posterior nasal aperture opens into nasopharynx
Auditory tubes
open into lateral wall of nasopharynx
Torus Tubarius
bulge over the cartilage tube
Salphingopharyngeal fold
runs inferior from torus tubarius
Pharyngeal recess
narrow space posterior to torus tubarius and salpingopharyngeal fold
Soft palate separates
nasopharynx and oropharynx
Pharyngeal isthmus
the communication between the oro- and nasopharynx (posterior to soft palate)
Pharyngeal tonsil
adenoids, superior region of posterior wall of naso pharynx
Enlarged adenoids
may block auditory tube, cause hearing impairment, difficulty breathing or talking
Oropharynx
posterior to oral cavity
Oropharyngeal isthmus
communication between oropharynx and oral cavity, between palatoglossal folds
Faucial isthmus
deeper passageway including oropharyngeal isthmus and extending to the PALATOPHARYNGEAL FOLDS
palatoglossal folds
first M-arch you see in the back of your mouth
Palatopharyngeal folds
deeper M-arch seen in back of mouth
Anterior wall of oropharynx
tongue
Lingual tonsil
covers posterior part of tongue
Palatine tonsils
on lateral walls between palatoglossal folds and palatopharyngeal folds
Tonsillar fossa
houses the palatine tonsils, depression between palatoglossal folds and palatopharyngeal folds
Tonsillar crypts
grooves seen on the palatine tonsils
Valleculae
depressions between tongue and epiglottis, where swallowed objects get lodged.
Laryngopharynx
posterior to larynx
Anterior wall of Laryngopharynx
posterior aspect of larynx
Laryngopharynx communicates with
inlet of larynx and esophagus
Piriform recess
lateral to cricoid cartilage, food my get lodged here
Superior constrictor anterior attachments
medial pterygoid plate and pterygomandibular raphe (same as buccinator)
pterygomandibular raphe
band of fibrous tissue running from pterygoid hamulus to body of mandible
Superior constrictor posterior attachments
median pharyngeal raphe and pharyngeal tubercle on occipital bone
Middle constrictor anterior attachment
stylohyoid ligament and horns of hyoid bone
Middle constrictor posterior attachment
median pharyngeal raphe (overlaps superior constrictor)
Inferior constrictor anterior attachment
thyroid and cricoud cartilage of larynx
Inferior constrictor posterior attachment
median pharyngeal raphe (overlaps middle constrictor)
Action of all constrictors?
constrict and shorten (elevate) the pharynx
Inferior constrictor has an additional action?
circular layer of muscle that acts as a sphincter, preventing air from entering the esophagus
Pulsion diverticulum
if you do not relax the inferior constrictor during swallowing you may cause a herniation of mucosa through the muscular layer
Stylopharyngeus origin
styloid process of temporal bone
Stylopharyngeus insertion
thyroid cartilage and inner wall of laryngopharynx
What muscles does the stylopharyngeus pass between?
superior and middle pharyngeal constrictors (along with glossopharyngeal)
Palatopharyngeus superior attachment
soft palate
Palatopharyngeus inferior attachment
thyroid cartilage and inner wall of laryngopharynx (same as stylopharyngeus)
Action of stylopharyngeus
shorten (elevate) pharynx and elevate larynx
Action of Palatopharyngeus
Elevates pharynx and larynx, depresses soft palate and narrows space palatopharyngeal folds
Salpingopharyngeus superior attachment
medial cartilage of auditory tube
Salpingopharyngeus inferior attachment
blends with Palatopharyngeus; some fibers insert on thyroid cartilage
Action of Salpingopharyngeus
Open the auditory tube, elevate pharynx and larynx
Velum
soft palate
Uvula
part of the soft palate
Soft palate composition
mucous and seromucous glands on inferior aspect and muscle
Soft palate attachment
hard palate anteriorly and walls of pharynx laterally
Palatoglossus muscle superior attachment
soft palate
Palatoglossus muscle inferior attachment
sides of tongue
Action of Palatoglossus muscle
depress soft palate, elevate tongue, narrow oropharyngeal isthmus (seal for sucking and swallowing)
Levator Veli Palatini origin
petrous part of temporal bone
Levator Veli Palatini insertion
soft palate
Action of Levator Veli Palatini
elevate soft palate and draw it posteriorly (MAIN mechanism for closing pharyngeal isthmus during swallowing or for speech)
Tensor Veli palatini origin
scaphoid fossa and lateral membranous wall of auditory tube
Tensor Veli palatini insertion
tendon via the pterygoid hamulus; the palatine aponeurosis attaches to posterior margin of the hard palate and opposite half of aponeurosis
palatine aponeurosis
tendon of tensor veli palatini becomes the aponeurosis after passing the hamulus
Action of Tensor Veli palatini
opens the auditory tube by pulling on its lateral membranous wall during swallowing or yawning
Innervation of Tensor Veli palatini
mandibular division of trigeminal n
Stylopharyngeus innervation
glossopharyngeal n
What nerve primarily innervates the pharyngeal and soft palate muscles?
Vagus n.
Recurrent laryngeal nerve supplies what muscles
voluntary muscles of the esophagus
Levator veli palatini is partially supplied by what nerve?
facial n
Sensory innervation to the soft palate and nasopahrynx is supplied by
Maxillary division of trigeminal n
Oropharynx and part of laryngopharynx sensory innervation is supplied by
glossopharyngeal n
What nerve supplies special sensory taste fibers and sensory fibers to the posterior 1/3 of tongue
glossopharyngeal n
What nerve supplies the mucus membrane of the auditory tube and middle ear cavity?
glossopharyngeal n.
Major portion of laryngopharynx is supplied by
vagus n.
What arteries contribute to supplying the pharynx?
maxillary a. (lesser palatine to soft palate), ascending pharyngeal a, superior thyroid a., inferior thyroid a, facial a. branches
What veins drain the pharynx
pharnygeal venous plexus, connections to internal jugular v
Lymph drainage of pharynx
retropharyngeal nodes -> deep cervical nodes -> jugular lymph trunks
Anterior 2/3 of the auditory tube
Cartilage superior and medially, but is membranous laterally
Posterior 1/3 of auditory tube is
embedded in the temporal bone
Function of auditory tube
equalize air pressure form middle ear cavity and atmosphere for optimal sensitivity to sound
Chronic obstruction of auditory tube
air is absorbed and replaced by serous fluid
Deglutition
swallowing
Tongue movement during deglutition
superiorly and posteriorly
Pharyngeal isthmus action during deglutition
closes due to levator veli palatini and superior constrictor
Auditory tube during deglutition
OPENS
Constrictor action during deglutition
contract in a sequential peristaltic wave
Pharynx action during deglutition
elevates past the bolus of food (glove action)
Larynx action during deglutition
elevates and epiglottis covers opening, glottis closes
Esophagus action during deglutition
sphincter relaxes to let bolus pass and immediately contracts to force bolus down
Changes during development
Oropharynx lengthens an laryngeal entrance stays in pharyngeal isthmus (projects into nasopharynx in infants, milk flows laterally around)
Benefits for infants and adults
Infants: suckle and breath; Adults: speech progression but more likely to choke
Pharynx role in vocalization
controls air in its lumen
Less air in pharynx
resonation at a higher sound frequency (high pitch)
High pitch mechanism
larynx is raised to reduce volume of oropharynx and pharyngeal isthmus narrows reducing volume of oral cavity