pharynx and soft palate Flashcards
goals of safe deglutition
1: bolus formed to prevent dispersion - needs to be of suitable size and consistency
2: differential pressures must develop for aboral propulsion
3: prevent entry of food into nasopharynx and larynx
4: suspends respiration while food is passing
5: rapid passage of food
structures involved in deglutition
mouth cheeks tongue teeth salivary glands palate pharynx
structures involved in respiration
nares nasal cavities nasopharynx oropharynx associated glands
goals of safe respiration
remove particulate matter
warm, humidify and cleanse air
structures involved in speech
lungs larynx nasal cavities sinuses nasopharynx oropharynx associated glands
production of speech
1: source of energy - elastic recoil of lungs moves air
2: oscillation of vocal cords
3: resonator - size and shape of
- pharynx
- oral cavity
- nasal cavity
- paranasal sinuses
pharynx
vertically oriented funnel-shaped half-cylinder
serves a passageway for air and food
suspended in midline from basal surface of occipital bone by submucosal layer
direct continuation of nasal and oral cavities
leads into larynx before continuing as esophagus
goes to cricoid cartilage/C6 vertebrae and then becomes esophagus
pharyngeal tubercle
basal surface of occipital bone from which pharynx is suspended by its submucosal layer
pharyngobasilar fascia
submucosal layer of pharynx from which pharynx is suspended from occipital bone
three regions of pharynx
nasopharynx
oropharynx
laryngopharynx
nasopharynx
posterior to posterior nasal apertures (choanae) of nasal cavities superior to soft palate contains: - adenoids - auditory tube - torus tubarius - tubal tonsils
oropharynx
posterior to fauces of oral cavity
contains:
- fauces/oropharyngeal isthmus
- palatine arches
-palatoglossal arch
- palotaoglossus muscle
- palatopharyngeal arch
- palatopharyngeus muscle
- palatine tonsilslaryngopharynx
posterior to larynx
extends from tip of epiglottis to beginning of esophagus at C6
internal walls:
posterior: nothing to note
lateral: pharyngeal muscles attaching to hyoid bone and thyroid cartilage
anterolaterally (piriform recess): mucosa overlies the medial surface of theyroid cartilage aand jsut superior to his, the thyrohyoid membrane
anteromedially: epiglottis, aditus to the larynx, posterior wall of larynx
tissue layers of pharyngeal wall (list)
mucosa
submucosa (pharyngobasilar fascia)
muscular
- inner layer
- outer layer
exterior (buccopharyngeal fascia)mucosal layer of pharynx
innermost layer of pharynx
has pharyngeal glands (mixed salivary glands)
has pseudostratified ciliated epitehlium in nasopharynx
stratified squamous epithelium in oropharynx and laryngopharynx
pharyngeal glands
mixed salivary glands in mucosal layer of pharyngeal wall
mucosa of nasopharynx
has pseudostratified ciliated epithelium
mucosa of oropharynx and laryngopharynx
has stratified squamous epithelium
pharyngobasilar fascia
submucosal layer of pharynx
strong continous layer of fascia tha tsupports the pharynx
muscular layer of the pharynx
has inner and outer layer, each with three muscles - inner longitudinal, outer circular
inner layer of muscular layer of pharynx
3 longitudinal/elevator muscles
palotopharyngeus
styloparyngeus
salpingopharyngeus
descend and insert into pharyngeal wall by blending with each other and the constrictors
elevate and shorten pharynx during swallowing
outer layer of muscular layer of pharynx
3 circular muscles
superior constrictor
middle constrictor
inferior constrictor
buccopharyngeal fascia
outer layer of pharynx
has a layer of loose areolar tissue
bones of pharyngeal skeleton
includes: base of skull (pharyngeal tubercle) medial pterygoid plate pterygomandibular raphe mandible hyoid bone thryroid cartilage cricoid cartilate
pterygomandibular raphe
part of pharyngeal skeleton
runs between hamulus of the medial pterygoid plate and the inner surface of the posterior mandible
both buccinator and portion of superior constrictor muscle of pharynx insert here
allows for continuity and coordination of these two muscles during deglutition
constrictor muscles
outer, circular layer of pharyngeal musculature
originate bilaterally from sides of head and neck
insert on midline fibrous pharyngeal raphe
each muscle partially overlapped by the muscle immediately caudal to it
sequential contraction aids in aboral (away from mouth) propulsion of food
gaps exist between base of skull and superior constrictor muscle of pharynx and between muscles themselves (pharyngobasilar fascia fills these gaps)
superior constrictor muscle
one of circular constrictor muscles of outer layer of pharynx
originates on pterygomandibular raphe and the adjacent bony structures (pterygoid hamulus and posterior end of hte mylohyoid line of hte mandible
forms part of a semi-cylander completed anteriorly by buccinator and obicularis oris muscles
middle constrictor muscle
one of the constrictor muscles of outer circle of pharynx muscular layer
originates mostly from the greater horn of the hyoid
inferior constrictor muscle
one of the constrictor muscles of the outer circular muscles of the muscular layer of the pharynx
originates from the thyroid cartilage and cricoid cartilage
has two parts: thyropharyngeal and cricopharyngeal
thyropharyngeal part of the inferior constrictor muscle
fibers overlap middle constrictor
cricopharyngeal part of inferior constrictor
major component of upper esophageal sphincter
upper esophageal sphincter
narrowest passage of entire GI tract
resting (basal) high pressure zone located at the junction of the laryngopharynx and esophagus
capable of rapid relaxation and contraction during swallowing which prevents swallowing air during inspiration and aspiration of regurgitated esophageal contents
gaps between pharyngeal constrictors
gap 1: levator veli palatini muscle
auditory tube
gap 2: stylopharyngeus muscle
glossopharyngeal nerve (CN IX)
gap 3: superior laryngeal nerve (internal branch; vagus)
superior laryngeal artery (branch of superior thyroid artery
gap 4: recurrent laryngeal nerve
inferior laryngeal artery (branch of inferior thyroid artery)
gap 1
between base of skull and superior constrictor
levator veli palatini muscle
auditory tube
gap 2
between superior and middle constrictors stylopharyngeus muscle glossopharyngeal nerve (CN IX)
gap 3
between middle and inferior constrictors
superior laryngeal nerve (internal branch; vagus)
superior laryngeal artery (branch of superior thyroid artery
gap 4
below inferior constrictor
recurrent laryngeal nerve
inferior laryngeal artery (branch of inferior thyroid artery)
stylopharyngeus
one of inner longitudinal muscles of pharynx
originates from styloid process
only muscle of pharynx innervated by glossopharyngeal nerve (CN IX)
salpingopharyngeus
one of muscles of inner longitudinal layer of pharynx
originates from auditory tube cartilage and terminates in pharyngeal wall after joining palotopharyngeus
elevates pharynx and participates with tensor veli palitini to open cartilaginous end of auditory tube durin gswallowing
palatopharyngeus
one of inner longitudial muscles of pharynx and also one of 5 paired muscles of soft palate
originates from palatine aponeruosis of soft palate
inserts on interior of lateral wall of pharynx and thyroid cartilage
3 actions:
- lowers soft palate
- constricts faucial isthmus
- shortens pharynx during swallowing by pulling it up, forwards and medial
innervated by vagus nerve
adenoids (nasopharyngeal tonsils)
lymphoid tissue within the pharyngeal fornix (roof)
in nasopharynx
auditory/pharyngotympanic/eustachian tube
part of nasopharynx
bony and cartilaginous tube with a funnel-shaped opening into the nasopharynx that equalizes pressure on either side of the tympanic membrane
torus tubarius
component of nasopharynx
elevation produced by the cartilage of the auditory tube
tubal tonsils
in nasopharynx
lymphatic tissue around the auditory opening
choana
posterior nasal aperture forming the boundary between nasal cavities and nasopharynx
fauces/oropharyngeal isthmus
part of oropharynx
passageway from the oral cavity to the oropharynx
bounded by soft palate, palatine arches and dorsum of the tongue
palatine arches
part of oropharynx
2 arches:
palatoglossal arch
palatopharyngeal arch
palatoglossal arches
one of two palatine arches part of oropharynx means anterior pillar of fauces mucosa overlying the palatoglossus muscle between the soft palate and tongue
palatoglossus muscle
palatoglossal arch overlies one of the 5 paired muscles of the soft palate elevates posterior tongue closes oropharyngeal isthmus innervated by vagus
palatopharyngeal arch
posterior pillar of the fauces
one of palatine arches of oropharynx
mucosa overlying palatopharyngeus muscle
between the soft palate and poterolateral wall of pharynx
palatopharyngeus muscle
overlayed by palatopharyngeal arch mucosa
one of the 5 paired muscles of the soft palate
elevates pharynx and larynx
innervated by vagus
palatine tonsils
lymphoid tissue lying in the tonsilar fossae between palatoglossal and palatopharyngeal arches
pharyngeal portion of tongue
vertically-oriented posterior 1/3 of tongue
forms anterior wall of oropharynx below fauces
contains lingual tonsil
lingual tonsil
nodules of lymphoid tissue on the pharyngeal portion of the tongue
epiglottis
posterior to pharyngeal portion of tongue
projects superiorly
connected to base of tongue by 3 folds:
- 2 lateral glossoepiglottic folds
- median glossoepiglottic fold
has valleculaeglossoepiglottic folds
connect epiglotis to base of tongue
valleculae
shallow depressions on the lingual surface of the epiglottis between each lateral glossoepiglotic fold and the median glossoepiglotic fold
important landmark for endotracheal intubation
foreign bodies often lodge here
piriform recesses (sinuses, fossae)
anterolateral recesses of the pharynx extending forward on either side of the larynx
superior laryngeal neves, arteries and veins lie under the mucosal folds, having entered through the thyrohyoid membrane
foreign bodies often lodge here
zone of sparse fibers/upper esophageal sphincter
between cricopharyngeus and thyropharyngeus portions of inferior constrictor
area where the mucosa is unsupported by musculature
retropharyngeal space
area of loose connective tissue between the buccopharyngeal fascia of the pharynx and prevertebral fascia
permits necessary expansion and movement of pharynx, larynx, trachea and esophagus
extends from base of skull to infrahyoid area - becomes retrovisceral space
lateropharyngeal space
lateral extension of retropharyngeal space subdivided into anterior and posterior part anterior: - pterygoid plexus - retromandibular vein - external carotid artery posterior - carotid sheath and its contents
retrovisceral space
retropharyngeal space extends into this
frequently terminates in superior mediastinum at level of T3-T4 when the prevertebral fascia obliterates the space by adhering to the esophagus
arterial blood supply to pharynx
mainly from ascending pharyngeal artery but also from branches of external carotid (esp. tonsillar and ascending palatine branches of facial)
pharyngeal venous plexus
collects blood on the posterior aspect of the pharynx
superiorly drains into pterygoid plexus (in infratemporal fossa)
inferiorly drains into IJV or into tributaries of it
pharyngeal plexus
on external surface of pharynx within the buccopharyngeal fascia
formed by sensory branches of glossopharyngeal nerve (CN IX) and sensory and motor branches from vagus nerve
motor innervation of muscles of pharynx
all by vagus except stylopharyngeus = glossopharyngeal
sensory innervation of nasopharynx
pharyngeal branch of maxillary nerve (V2)
sensory innervation of oropharynx
glossopharyngeal nerve
sensory innervation of laryngopharynx
vagus nerve
waldeyer’s ring
provides immune defense to pharynx oblique circumpharyngeal ring of mucosa-associated lymphoid tissue (MALT) guards entrance to respiratory and digestive tracts composed of: - nasopharyngeal tonsils - palatine tonsils - tubal tonsils - lingual tonsils
hard palate
anterior 2/3 of palate
palatine processes of maxillary bones and horizontal plate of palatine bones
mucosa is thick, adherent and contains numerous minor salivary glands
serves as a partition between oral and nasal cavities
soft palate
posterior 1/3
serves to close off the oropharynx from the nasopharynx during deglutition
thick fold of mucosa suspended from the posterior border of the hard palate
hangs down as a mobile projection in front of the posterior pharyngeal wall
forms anterior border of nasopharynx
contains 5 paired muscles, mucous glands, vessels, nerves, lymphatics, two arches, uvula
the five paired muscles of the soft palate (list)
tensor veli palatini levator veli palatini palatoglossus muscle palatopharyngeus muscle uvular muscle
all innervated by CN X except tensor veli palatini (CN V3)
tensor veli palatini
one of the 5 paired muscles of the soft palate
tenses soft palate prior to elevation
innervated by CN V3
levator veli palatini
elevates soft palate
one of the 5 paired muscles of soft palate
innervated by vagus
uvular
one of the 5 paired muscles of the soft palate
stiffens the soft palate
innervated by vagus
uvula
part of soft palate
projects downward from the posterior margin
palatine tonsils
largest accumulation of lymphoid tissue in waldeyer’s ring
thin capsule covers deep surface, separating it from the pharyngobasilar fascia
tonsillar fossa
depression between palatoglossal and palatopharyngeal arches
tonsillar branch of facial artery
larges to many vessels nourishing the palatine tonsil
most vessels enter via deep surface of interior pole
paratonsillar vein
drains into facial vein from palatine tonsils
lymphatic drainage of palatine tonsils
to jugulodiagastric node
