Anatomy: Palate and PPF Flashcards
what is the PPF?
Pterygopalatine fossa
- located postero-inferiorly to apex of orbit, posterior to maxillary sinus, deep to infratemporal region
- contains pterygopalatine ganglion: receives PS via V2
- infratemporal fossa is lateral to PPF
- palate is inferior to PPF
- orbit/maxillary sinus anterior
- nasal cavity is medial
how can you access PPF?
transantrally, through the maxillary sinus.
- the upper lip is elevated and maxillary sinus is entered anteriorly
- can be used to remove tumors or ligate sphenopalatine a in cases of chronic epistaxis
general contents of PPF?
3rd portion of maxillary a.
maxillary branch of V2
pterygopalatine ganglion
boundaries of PPF?
lateral = pterygomaxillary fissure
superior=sphenoid (no foramina)
ant=maxillary bone
medial = palatine bone
inferior = open via pterygopalatine canal
posterior= pterygoid process of sphenoid bone
what does pterygomaxillary fissure transmit?
- doorway into PPF
- found in lateral boundary, comminicates with infratemporal fossa
- transmits maxillary a; posterior superior alvolar a.v.n.
what does inferior orbital fissure transmit?
- anterior (facing anteriorly and looking up)- communicates with orbit
- transmits:
infraorbital a.v.n.
zygomatic a.v.n.
what does sphenopalatine foramen transmit?
- located in upper part of palatine bone (medial border)- communicates with nasal cavity
- transmits::
sphenopalatine a/v, nasopalatine n, posterior superior lateral nasal n.
what does pterygopalatine canal transmit?
- located in inferior wall of PPF - communicates with palate and oral cavity (opens up to hard palate)
transmits:
descending palatine a.
greater/lesser palatine nn.
foramen rotundum
located in posterior of PPF; lateral of the three
- communicates with middle cranial fossa
- transmits V2 to PPF
pterygoid canal
- located in posterior PPF; middle of three posterior openings
- communicates with middle cranial fossa near foramen lacerum
- transmits nerve and artery of pterygoid canal
pharyngeal canal
- located in posterior PPF, medial most of openings
- communicates with nasopharynx
- transmits pharyngeal a.v.n.
what are branches of maxillary artery in PPF?
- posterior superior alveolar a.
- descending palatine a.
- infraorbital a.
- artery of pterygoid canal
- pharyngeal a.
- sphenopalatine a.
posterior superior alveolar a.
- enters un-named foramen on maxillary bone
- supplies maxillary teeth and gingiva and maxillary sinus
infraorbital artery
exits the PPF anteriorly via inferior orbital fissure
- courses through floor of orbit in infraorbital canal, and exits face via infraorbital foramen
- supplies floor of orbit, maxillary sinus, maxillary teeth, skin of face via:
1. zygomatic a.
2. middle superior alveolar a.
3. anterior superior alveolar a.
4. nasal branches
5. superior labial branches
descending palatine a.
exits the PPF inferiorly via the pterygopalatine canal
- supplies palate, nasal cavity, palatine tonsil via:
1. greater palatine a.
2. lesser palatine a.
artery of pterygoid canal
exits PPF posteirorly via pterygoid canal
- supplies nasopharynx, auditory tube, tympanic cavity
pharyngeal a.
exits PPF posteriorly via pharyngeal canal - courses through medial wall of sphenoid sinus to open into nasopharynx
- supplies nasopharynx, sphenoid sinus, auditory tube
sphenopalatine a.
exits PPF medially via sphenopalatine foramen - supplies nasal cavity
what does maxillary nerve provide?
CN V2, only GSA!
V2 exits the middle cranial fossa via the forament rotundum to enter the PPF
- V2 provides sensory to the middle dermatome of the face, nasal cavity, paranasal sinuses; maxillary teeth
- distributes PS innervation from pterygopalatine ganlgion
what does V2 supply to the skull?
meningeal branch to dura of middle cranial fossa
zygomatic n.
branch of V2
- exits PPF anteriorly via inferior orbital fissure
- courses through floor and lateral wall of orbit then divides into two nn. which supply GSA innervation to face:
1. zygomaticofacial n.
2. zygomaticotemporal n. (gives rise to communicating branch to lacrimal n. of V1)
Note: route for autonomic fibers to the lacrimal gland
posterior superior alveolar n.
enters foramen in maxillary bone
supplies maxillary teeth and gingiva and maxillary sinus
infraorbital n.
exits PPF anteriorly via inferior orbital fissure
- courses through floor of orbit in infraorbital canal and exits to face via infraorbital foramen
- supplies floor of orbit, maxillary sinus, maxillary teeth, skin of face via:
1. middle/anterior superior alveolar n.
2. inferior palpebral nn.
3. external nasal branches
4. superior labial branches
Pterygopalatine nn.
suspend the pterygopalatine ganglion to V2
- there are x2
- carry PS nn. to pterygopalatine ganglion.
greater palatine n.
- exits PPF inferiorly via pterygopalatine canal to oral cavity
- supplies hard palate
- supplies nasal cavity via posterior inferiror lateral nasal n.
lesser palatine n.
exits PPF inferiorly via pterygoplatine canl to oral cavity, supplies soft palate and tonisillar bed
posterior superior lateral nasal n.
exits PPF medially via sphenopalatine foramen to enter nasal cavity, supplies lateral wall of nasal cavity
pharyngeal n.
exits PPF posteriorly via pharyngeal canal to nasopharynx, supplies nasopharynx.
n. of pterygoid canal
enters PPF posteriorly via pterygoid canal
carries autonomics to PPG
nasopalatine n.
exits PPF via the sphenopalatine foramen to nasal cavities
supplies nasal cavity
then passes through incisive foramen to supply anterior hard palate
nerve blocks to PPF?
nasopalatine n. block: anesthetic injected near incisive forament
greater palatine n. block: anesthetic injected near greater palatine foramen
PPG
pterygopalatine ganglion
- suspended from V2 by pterygopalatine nn. contains cell bodies of post PS neurons. the PPG receives pre fibers from facial n (via greater petrosal n.) and post fibers from the deep petrosal n. these autonomic fibers then distribute via various branches of V2 to the mucus glands of the deep head (nasal and paranasal cavities, palate, pharynx) and to the lacrimal gland
nerve of pterygoid canal
carries PS (pre) and symp (post) to PPG
- composed of greater petrosal n.(pre PS) and deep petrosal n.(post symp)
- Pathway of autonomic innervation to lacrimal gland and mucous-secreting glands of head.
greater petrosal n.
PS!
- pathway of PS fibers going to PPG
- pre cell bodies located in brainstem in salivatory nucleus
- pre fibers travel with CN VII to greater petrosal nerve to nerve of pterygoid canal to pterygopalatine ganglion
- post fibers then distribute via branches of the maxillary n.
deep petrosal n.
carries Symp!
- pathway of Symp going to PPG
- pre cell bodies located in IMLCC from T1/4
- pre fibers travel within symp chain to SCG
- post cell bodies located in the SCG
- post fibers from internal carotid n travel with deep petrosal n to the nerve of pterygoid canal and pass through PPG without synapsing
- post fibers then distribute via branches of the maxillary n.
PS innervation to lacrimal gland
pre cell bodies: salivatory nucleus
- pre fibers: travel with CN VII via greater petrosal n.
- post bodies: pterygopalatine ganglion
post fibers: distribute the zygomatic branch of V2 and the lacrimal branch of V1
** increase lacrimal gland secretions**
Symp innervation to lacrimal gland
- pre cell bodies located in upper thoracic spinal levels (T1-4)
- pre fibers enter symp chain and ascend
- post cell bodies in SCSG; fibers distribute via internal carotid n. to deep petrosal n.
- greater and deep petrosal nn. merge to form the n. of pterygoid canal
- post fibers distribute with zygomatic branches of V2 and lacrimal branches of V1.
** vasomotor fn. creates more watery lacrimal fluid **
PS innervation to mucous-secreting glands of head (nasal cavities and paranasal sinuses)?
pre bodies: salivatory nucleus
pre fibers: facial n. travels into midle cranial fossa via greater petrosal n, becomes n. of pterygoid canal..
post bodies: pterygopalatine ganglion
- post fibers: travel with branches of V2 to distribute to nasal cavities and paranasl sinuses
Symp innervation to nasal cavities and paranasal sinuses?
pre bodies: T1-4
post bodies: SCG
post fibers: form internal carotid n –> deep petrosal n.
- deep petrosal n. joins to form n. of pterygoid canal
- post fibers distribute with branches of V2
Palate general features
hard (ossified)
soft (musculofascial)
- forms boundaryb/w nasal and oral cavities
- superior nasal surface covered with resp. mucosa
- inferior oral surface covered with typical oral mucosa
what is the structure of the hard palate? foramina?
anterior 2/3 of palate
- bony, internal skeleton formed by: palatine processes of maxillary bones and horizontal plate of palatine bones
- formina: incisive foramen, greater palatine foramine, lesser palatine foramina
what travels through incisive foramen?
nasopalatin n. and greater palatine a.
what makes up mucosa of hard palate?
- mucous secreting palatine glands
- transverse palatine folds
- palatine raphe
note: anesthetic injection is very painful here because the mucosa is very tightly adhered to the underlying bone, thus anesthetics are usually injected in superior gingiva mucosa
structure of soft palate?
posterior 1/3 of palate
- mobile, allows for swallowing
- presses against tongue to hold food in oral cavity
- presses against roof of pharynx to prevent food from passing into nasal cavity
- composed of palatine aponeurosis and overlying mucosa with palatine glands
- ends in posterior projection called the uvula
fauces
passage from oral cavity to pharynx
boundaries:
- superior: palate
- inferior: base of tongue
- lateral: faucial pillars
what makes up the faucial pillars?
- palatoglossal arch: most anterior
- palatopharyngeal arch: more posterior
- isthmus of fauces: constricted portion of fauces bounded by palatoglossal pillars
tonisllar bed/fossa
- depression b/w palatoglossal and palatopharyngeal folds
- houses palatine tonsil
structures forming tonsilar bed?
- superior constrictor, hyoglossus, middle constrictor, glossopharyngeal n, tonsillar vessels
palatine tonsil
- lymphoid tissue
- arterial supply: facial a, palatine branch of ascending pharyngeal, ascending palatine a, dorsal lingual a, lesser palatine a (highly vascularized area, thus there may be complications with tonsillectomy)
- venous drainage: tonsillar plexus and pharyngeal plexus of v.
Palatoglossus
O: soft palate
I: tongue
n: vagus
fn: pulls tongue and soft palate together during swallowing
Palatopharyngeus
O: soft palate
I: thyroid cart.
N: vagus
fn: swallowing (pulls laryngopharynx over food bolus and prevents food from going into larynx)
musculus uvulae
o: soft palate
I: uvula
n: vagus
fn: shortens and elevates ubula
tensor veli palatini
- more anterior/lateral
O: lateral side of auditory tube
I: attaches to palatine aponeurosis
N: trigeminal n (V3) ** only mm. of palate not innervated by CN X ***
fn: tenses palate; fns. during mastication and swallowing; opens membranous portion of auditory tube (by pulling laterall, it gives greater mechanical advantage for levator veli palatini)
Levator veli palatini
O: medial side of auditory tube
I: passes b/w base of skull and superior constrictor to attach to palatine aponeurosis
N: vagus
fn: elevate palate; pull against roof of pharynx - prevents food from going into nasal cavity
What is innervation to almost all mm. of palate? what happens with loss of this n?
all mm. except tensor veli palatini (CN V3) are innervated by vagus n.
- with paralysis of CN X, the soft palate and the faucial pillars will sag, also uvula will deviate to UNAFFECTED side.
arteries of palate?
arterial:
- maxillary artery (3rd portion): greater and lesser palatine
- facial a: ascending palatine a.
venous drainage of palate?
pterygoid plexus of vv to maxillary v.
how is sensory supplied to the palate?
Trigeminal n (V2) via:
- nasopalatine n.
- greater palatine
- lesser palatine n.
- note: these branches of V2 also distribute autonomic fibers tot he blood vessels and glands of the palate
