Pterygopalatine Fossa Flashcards
Where do all of the upper teeth receive their innervation and blood supply?
From maxillary nerve and artery that pass through the PP fossa
What forms the anterior wall of the PP fossa?
posterior surface of the maxilla
What forms the medial wall of the PP fossa?
vertical plate of palatine bone
What forms the posterior wall of the PP fossa?
pterygoid process of sphenoid bone
What foramen does the maxillary nerve enter the PP fossa through?
Foramen Rotundum
What passes through the anterior opening of the pterygoid canal?
Nerve of pterygoid canal, which consists of GVE parasympathetics in Greater petrosal nerve from CN VII and sympathetic fibers from the deep petrosal nerve
Describe the position of the anterior openeing of the pterygoid canal relative to the foramen rotundum.
Anterior opening of the pterygoid canal is medial and inferior to the foramen rotundum. (p 941 gray’s)
Which gateways allow structures to enter/leave the posterior wall of the PP fossa?
foramen rotundum, pterygoid canal, and palatovaginal canal
What space does the palatovaginal canal connect the PP fossa to?
It opens in the posterior wall of the PP fossa and leads to the nasopharynx
What gateway is on the floor of the PP fossa? What does it go to?
Palatine canal. Leads to the roof of the oral cavity (hard palate)
What gateway lies on the medial wall of the PP fossa?
sphenopalatine foramen, which leads to lateral wall of nasal cavity
What gateway lies on the lateral wall of the PP fossa?
Pterygomaxillary fissure, leads to IT fossa
What gateway opens in the superior aspect of the anterior wall of the PP fossa? What does it lead to?
Inferior orbital fissure, leads to floor of orbit
What type of fibers does the nerve of the pterygoid canal carry?
GVE parasymp preganglionics from greater petrosal branch of CN VII
GVE sympathetic postganglionics from deep petrosal branch of carotid plexus
What passes through the inferior orbital foramen?
Infra-orbital nerve, orbital branches, and zygomatic nerve
Why can a lesion along the course parasympathetics of the facial nerve be very severe?
Some of the parasympathetics of the facial nerve are ultimately carried to the lacrimal gland along the branches of the CN V1. If these are severed, the lacrimal gland will cease to function and severe loss of vision will follow due to ‘dry-eye’
What passes through the incisive foramen?
The greater palatine artery passes up from the palate into the nasal cavity.
The nasopalatine nerve passes down from the nasal cavity into the palate.
What forms the roof of the PP fossa?
greater wing of the sphenoid bone
Starting in the middle cranial fossa, what space would a wire poked through the foramen rotundum end up in?
Pterygopalatine fossa
What does the pterygoid canal transmit and between what to spaces?
Conducts the artery and nerve of pterygoid canal from the base of the skull (just anterior to the foramen lacerum) to the PP fossa
What is another name for pharyngeal canal? What passes through it and between what two areas?
Palatovaginal canal.
Pharyngeal branch of maxillary artery and pharyngeal branch of maxillary nerve from the PP fossa to the nasopharynx
What passes through the inferior orbital fissure and between what two spaces?
Orbital branches of V2 (zygomatic and infraorbital nerves) and the infraorbital artery between the PP fossa and orbit
What passes through the sphenopalatine foramen and between what areas?
Sphenopalatine artery and nasopalatine nerve between the superior-medial wall of PP fossa to the lateral wall of nasal cavity
What two areas do the lesser and greater palatine foramen connect and what passes through them? Which foramen is anterior?
PP fossa to the roof of the oral cavity. they carry lesser and greater palatine nerves. Greater palatine foramen is more anterior to the lesser.
What passes through the posterior superior alveolar foramen and between what two areas?
posterior superioralveolar artery and nerve from the IT fossa into the bony wall of the maxillary sinus and superior dental arch.
What is the terminal branch of the maxillary artery?
sphenopalatine artery, which enters the nasal cavity via the sphenopalatine foramen
What are the branches of the PP part of the maxillary artery?
infraorbital, zygomatic, descending palatine, posterior superior alveolar and sphenopalatine
Of the 9 canals in the PP fossa, only one does not transmit an artery. Which one?
Foramen rotundum only has the nerve
What is the parent branch of the greater and lesser palatine arteries?
descending palatine artery off the maxillary
Which artery in the PP fossa makes a characteristic loop that can help you identify it in lab?
3rd part of maxillary artery
What is the parent artery that zygomatic artery branches off of?
opthalmic artery in orbit. This is in contrast to the zygomatic nerve, which is a branch off the maxillary nerve in the PP fossa
Describe the pathway that parasympathetics of CN VII take to reach the lacrimal gland from the cranial cavity.
Parasymp preganglionic cell body in the brainstem, then passes through internal auditory meatus then through hiatus of greater petrosal nerve, then through pterygoid canal via the pterygoid nerve, then into pterygopalatine ganglion synapse, then postganglionics travel with the zygomatic nerve (a branch of V2) through the infraorbital fissure into the orbit, then piggy-back onto lacrimal n. (a branch of V1) to reach lacrimal gland.
If any of this is disrupted, blindness will likely follow due to dysfunction of lacrimal glands.
What type of fibers run in greater petrosal nerve?
SA, GVE parasymp preganglionics
eventually sympathetics will join after it merges with deep petrosal nerve to form pterygoid nerve
What type of fibers run in greater petrosal nerve?
SA, GVE parasymp
What CN is lesser petrosal nerve associated with?
CN IX
Why is the anastomoses between the greater palatine artery and the anterior ethmoidal artery in the nasal cavity clinically important?
It is the most common site of nose-bleeds. The anastomoses is directly superior and anterior to the incisive canal. (p1026 grays)
