Nasal Cavity And Pterygopalatine Fossa Flashcards
What are the bony parts of the nose?
Nasal bones, frontal process of maxilla, nasal part of frontal bone and nasal spine, bony part of nasal septum
What are the cartilaginous parts of the nose?
2 lateral cartilages, 2 alar cartilages, and septal cartilage (nasal septum)
What lines the nasal cavity?
Nasal mucosa
Except for the vestibule of the nose (considered an external portion)
Nasal mucosa is firmly connected to what?
The periosteum of the bony parts of the nasal cavity and the perichondrium of the cartilaginous nasal components
What do the areas lined with nasal mucosa constitute?
The respiratory area (inferior 2/3) and the olfactory area (superior 1/3)
The olfactory area of the nasal cavity has specialized nasal mucosa that contains what?
The peripheral nerve endings of the olfactory nerve (CN I) for special sense of olfaction
What makes up the roof of the nasal cavity?
Frontal bone, ethmoid bone and sphenoid bone
What forms the floor of the nasal cavity?
Palatine process of maxilla and horizontal plate of palatine bone
What forms the medial wall of the nasal cavity?
Nasal septum (perpendicular plate of ethmoid, vomer, septal cartilage, nasal crests of maxillary and palatine bones)
What forms the lateral wall of the nasal cavity?
Superior, middle and inferior nasal conchae
Which structures pass through the sphenopalatine foramen?
Sphenopalatine A and nasopalatine N
What is the sphenoethmoid recess an opening of?
Sphenoid sinus
What is the superior nasal meatus an opening of?
Ethmoidal sinuses
What is the middle nasal meatus an opening of?
Frontal sinus
Maxillary sinus also opens into middle nasal meatus in posterior part of semilunar hiatus at the maxillary ostium (below ethmoid bulla)
What is the inferior nasal meatus an opening of?
Nasolacrimal duct
The nasal conchae divided the nasal cavity into what 4 passages?
Sphenoethmoidal recess, superior nasal meatus, middle nasal meatus, inferior nasal meatus
Most of the blood supplied to the nasal cavity is to what?
The lateral and medial walls
Which arteries provide arterial blood supply to the nasal cavity?
Opthalamic artery via anterior and posterior ethmoid arteries
Maxillary artery via sphenopalatine and greater palatine A
Facial artery via superior labial and lateral nasal branches
Venous drainage to the nasal cavity is through which veins?
Sphenopalatine, facial and ophthalmic veins
What is the Kiesselbach area?
Where all five arteries supplying the nasal cavity come together in a capillary bed and can bleed profusely
What is the pterygopalatine fossa?
A small pyramid shaped space that is found inferior to the apex of the orbit
What is the anterior boundary of the pterygopalatine fossa?
Maxillary tuberosity
What is the posterior boundary of the pterygopalatine fossa?
Pterygoid process of sphenoid (lateral plate)
What is the medial boundary of the pterygopalatine fossa?
Perpendicular plate of palatine bone
What is the lateral boundary of the pterygopalatine fossa?
Opens into infratemporal fossa via pterygomaxillary fissure
What is the roof of the pterygopalatine fossa?
Greater wing of sphenoid (incomplete)
What is the floor of the pterygopalatine fossa?
Pyramidal process of palatine bone
What does the superior opening of the pterygopalatine fossa open into?
Inferior orbital fissure
What does the inferior opening of the pterygopalatine fossa open into?
It is closed except for at the palatine foramen
What are the contents of the pterygopalatine fossa?
Maxillary nerve (CN V2), pterygopalatine ganglion and third part of maxillary artery
Describe the innervation to the lacrimal gland
Maxillary nerve -> zygomatic nerve -> zygomaticotemporal nerve -> has a communicating branch that conveys parasympathetic fibers to the lacrimal nerve (CN V1) -> to lacrimal gland
Parasympathetic fibers to the pterygopalatine ganglion are from what?
The facial nerve (CN VII) via the greater petrosal nerve which joins the deep petrosal nerve to form the nerve of the pterygoid canal
The fibers from the greater petrosal nerve synapse in the ganglion
Describe the sympathetics of the pterygopalatine fossa
The deep petrosal nerve arises from the internal carotid plexus and conveys postsynaptic sympathetic fibers which join branches of the maxillary N via the pterygopalatine ganglion but do not synapse there
Presynaptic sympathetic fibers synapse in the superior cervical ganglion
Which nerves are in the pterygopalatine fossa?
Infraorbital N, zygomatic N, orbital branches (CN V2), maxillary N (CN V2), nerve of pterygoid canal (greater and deep petrosal nerves), greater and lesser palatine N, medial and lateral superior and posterior inferior nasal branches from nasopalatine N (V2)
Which artery is within the pterygopalatine fossa?
Maxillary A including descending palatine, posterior-superior alveolar A, infraorbital A, artery of pterygoid canal and sphenopalatine A
Which structures pass through the inferior orbital fissure to exit the pterygopalatine fossa?
Zygomatic branch of maxillary N
Infraorbital A and inferior opthalamic vein
Communicates with the orbit
Which structures pass through the foramen rotundum of the middle cranial fossa to enter the pterygopalatine fossa?
Maxillary N
Which structures pass through the pterygoid canal at the base of the skull to enter the pterygopalatine fossa?
N of pterygoid canal (greater and deep petrosal)
A of pterygoid canal
Which structures pass through the greater palatine canal to the exit the pterygopalatine fossa to go to the oral cavity?
Greater and lesser palatine N
Descending palatine A
Communicates with the oral cavity
What is the lesser palatine canal?
A branch from the greater palatine canal
Which structures pass through the sphenopalatine foramen to exit the pterygopalatine fossa?
Nasopalatine N and sphenopalatine A
Connects to the nasal cavity
What is the most common cause of epistaxis?
Local trauma or trauma to the face
Where do most cases of epistaxis occur?
In the anterior part of the nose with the bleeding usually arising from Kiesslebach’s plexus
Posterior epistaxis usually arises from what?
The posterior nasal cavity via branches of the sphenopalatine arteries
What structures pass through the pterygomaxillary fissure?
Posterior superior alveolar N
Terminal part of the maxillary A
Leaving fossa to enter the infratemporal fossa
What passes through the pharyngeal canal to exit the pterygopalatine fossa and enter the nasal cavity?
Pharyngeal branches of the maxillary N and A
