Nasal Anatomy Flashcards
Name the 3 divisions of the nasal cavity
1) Nasal vestibule
2) Nasal cavity
a) respiratory region (inferior)
b) olfactory epithelium
Describe the lining of the three divisions of the nasal cavity
- Nasal vestibule - skin (stratified squamous epithelium, keratinised to non-keratinised)
- Respiratory region of nasal cavity - respiratory epithelium (ciliated pseudostratified columnar epithelium) with sero-mucinous glands
- Olfactory region of nasal cavity - olfactory epithelium lined by olfactory cells with olfactory receptors
What three structures make up the nasal septum
- perpendicular plate of ethmoid bone
- vomer bone
- septal cartilage
What structures make up the lateral walls of the nasal cavity
- cribriform plate of the ethmoid bone (roof)
- medial plate of the pterygoid process of sphenoid bone
- the perpendicular plate of the palatine bone
- the medial surface of the lacrimal and maxillary bones
- the (superior, middle &) inferior concha
What are nasal conchae & what is their function
Curved shelves of bone that project out of the lateral walls of the nasal cavity to increase surface area
The superior and middle nasal concha are formed by ________ bone, while the inferior nasal concha is formed by ________ bone
The superior and middle nasal concha are formed by the ethmoid bone, while the inferior nasal concha is formed by its own bone
Where are the superior, middle & inferior conchae each located
- Superior meatus - between superior & middle conchae
- Middle meatus - between middle & inferior conchae
- Inferior meatus - between inferior conchae & nasal cavity floor
What does the inferior meatus drain
nasolacrimal duct
What does the middle meatus drain
- frontal & maxillary sinuses
- anterior & middle ethmoidal air cells
What structure drains anterior ethmoid air cells
Semilunar hiatus in the middle meatus
What structure drains middle ethmoid air cells
Ethmoidal bulla in the middle meatus
Where is the sphenoethmoidal recess located
superiorly and posteriorly to the superior concha
What does the sphenoethmoidal recess & where does it drain to
it drains the posterior ethmoid air cells and sphenoid sinuses into the superior meatus
Name the three openings of the nasal cavity
- Cribriform plate of ethmoid bone
- Sphenopalatine foramen
- Incisive canal
What passes through the cribriform plate
fibres of the olfactory nervehydrogenhydrogen
What is the role of the sphenopalatine foramen
Allows communication between the nasal cavity and pterygopalatine fossa
What passes through the sphenopalatine foramen
- sphenopalatine artery
- nasopalatine nerve
- superior nasal nerves
What is the role of the incisive canal
Allows communication between the nasal cavity and the incisive fossa of the oral cavity
What passes through the incisive canal
- nasopalatine nerve
- greater palatine artery
What 2 arteries supply the superior part of the nasal cavity
Anterior & posterior ethmoidal artery
What artery supplies the middle part of the nasal cavity
Sphenopalatine artery
What 3 arteries supply the middle part of the nasal cavity
Greater palatine artery (branch of sphenopalatine artery),
Lateral nasal artery & septal branch of superior labial artery
What artery does the anterior &b posterior ethmoidal artery originate from
Branch of ophthalmic artery
What artery does the sphenopalatine artery originate from
Maxillary artery
What artery does the lateral nasal artery & superior labial artery originate from
Facial artery
Summarise the arterial supply to the nasal cavity
- Interior carotid artery → opthalmic artery → anterior ethmoidal and posterior ethmoidal artery
- External carotid artery → maxillary artery → sphenopalatine and greater palatine artery
- External carotid artery → facial artery → superior labial artery and lateral nasal artery
What foramen does the sphenopalatine artery go through to reach the nasal cavity
Sphenopalatine foramen
What foramen does the anterior & posterior ethmodial arteries go through to reach the nasal cavity
A & P ethmoidal foramen
Where does the sphenopalatine artery travel to become the greater palatine artery
Descend the greater palatine canal, travels anteriorly, inferior to the hard palate before ascending the incisive canal
What artery’s form the Kiesselbach’s plexus
Anteriro ethmoidal artery
Posterior ethmoidal artery
Sphenopalatine artery
Superior labial artery
Greater palatine artery
What is the clinical relevance of the Kiesselbach’s plexus
Any disruption to Kiesselbach’s plexus can lead to epistaxis due to the rich blood supply
Describe the olfactory pathway
- Receptor cells in the olfactory epithelium
- Pass up through cribiform plate
- Synapse with olfactory bulb (ganglia)
- These neurons pass along the olfactory tract
- To temporal lobe and olfactory areas
Where is the olfactory bulb located
On the superior surface of the cribriform plate, above the nasal cavity
What two nerves provide general sensory innervation to the nasal cavity
nasopalatine and nasociliary nerve
What is the nasopalatine nerve a branch of
Maxillary nerve
What is the nasociliary nerve a branch of
Ophthalmic nerve
What nerve supplies the anterosuperior section of the nasal cavity
nasociliary nerve (branch of ophthalmic nerve - CN V1)
What nerve supplies the inferoposterior section of the nasal cavity
nasopalatine nerve (branch of maxillary nerve - CN V2)
