Nasal Anatomy

Question 1

Name the 3 divisions of the nasal cavity

Answer 1

1) Nasal vestibule
2) Nasal cavity
a) respiratory region (inferior)
b) olfactory epithelium

Question 2

Describe the lining of the three divisions of the nasal cavity

Answer 2

• 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

Question 3

What three structures make up the nasal septum

Answer 3

• perpendicular plate of ethmoid bone
• vomer bone
• septal cartilage

Question 4

What structures make up the lateral walls of the nasal cavity

Answer 4

• 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

Question 5

What are nasal conchae & what is their function

Answer 5

Curved shelves of bone that project out of the lateral walls of the nasal cavity to increase surface area

Question 6

The superior and middle nasal concha are formed by ________ bone, while the inferior nasal concha is formed by ________ bone

Answer 6

The superior and middle nasal concha are formed by the ethmoid bone, while the inferior nasal concha is formed by its own bone

Question 7

Where are the superior, middle & inferior conchae each located

Answer 7

• Superior meatus - between superior & middle conchae
• Middle meatus - between middle & inferior conchae
• Inferior meatus - between inferior conchae & nasal cavity floor

Question 8

What does the inferior meatus drain

Answer 8

nasolacrimal duct

Question 9

What does the middle meatus drain

Answer 9

• frontal & maxillary sinuses
• anterior & middle ethmoidal air cells

Question 10

What structure drains anterior ethmoid air cells

Answer 10

Semilunar hiatus in the middle meatus

Question 11

What structure drains middle ethmoid air cells

Answer 11

Ethmoidal bulla in the middle meatus

Question 12

Where is the sphenoethmoidal recess located

Answer 12

superiorly and posteriorly to the superior concha

Question 13

What does the sphenoethmoidal recess & where does it drain to

Answer 13

it drains the posterior ethmoid air cells and sphenoid sinuses into the superior meatus

Question 14

Name the three openings of the nasal cavity

Answer 14

• Cribriform plate of ethmoid bone
• Sphenopalatine foramen
• Incisive canal

Question 15

What passes through the cribriform plate

Answer 15

fibres of the olfactory nervehydrogenhydrogen

Question 16

What is the role of the sphenopalatine foramen

Answer 16

Allows communication between the nasal cavity and pterygopalatine fossa

Question 17

What passes through the sphenopalatine foramen

Answer 17

• sphenopalatine artery
• nasopalatine nerve
• superior nasal nerves

Question 18

What is the role of the incisive canal

Answer 18

Allows communication between the nasal cavity and the incisive fossa of the oral cavity

Question 19

What passes through the incisive canal

Answer 19

• nasopalatine nerve
• greater palatine artery

Question 20

What 2 arteries supply the superior part of the nasal cavity

Answer 20

Anterior & posterior ethmoidal artery

Question 21

What artery supplies the middle part of the nasal cavity

Answer 21

Sphenopalatine artery

Question 22

What 3 arteries supply the middle part of the nasal cavity

Answer 22

Greater palatine artery (branch of sphenopalatine artery),
Lateral nasal artery & septal branch of superior labial artery

Question 23

What artery does the anterior &b posterior ethmoidal artery originate from

Answer 23

Branch of ophthalmic artery

Question 24

What artery does the sphenopalatine artery originate from

Answer 24

Maxillary artery

Question 25

What artery does the lateral nasal artery & superior labial artery originate from

Answer 25

Facial artery

Question 26

Summarise the arterial supply to the nasal cavity

Answer 26

- 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

Question 27

What foramen does the sphenopalatine artery go through to reach the nasal cavity

Answer 27

Sphenopalatine foramen

Question 28

What foramen does the anterior & posterior ethmodial arteries go through to reach the nasal cavity

Answer 28

A & P ethmoidal foramen

Question 29

Where does the sphenopalatine artery travel to become the greater palatine artery

Answer 29

Descend the greater palatine canal, travels anteriorly, inferior to the hard palate before ascending the incisive canal

Question 30

What artery’s form the Kiesselbach's plexus

Answer 30

Anteriro ethmoidal artery Posterior ethmoidal artery Sphenopalatine artery Superior labial artery Greater palatine artery

Question 31

What is the clinical relevance of the Kiesselbach's plexus

Answer 31

Any disruption to Kiesselbach's plexus can lead to epistaxis due to the rich blood supply

Question 32

Describe the olfactory pathway

Answer 32

1. Receptor cells in the olfactory epithelium 2. Pass up through cribiform plate 3. Synapse with olfactory bulb (ganglia) 4. These neurons pass along the olfactory tract 5. To temporal lobe and olfactory areas

Question 33

Where is the olfactory bulb located

Answer 33

On the superior surface of the cribriform plate, above the nasal cavity

Question 34

What two nerves provide general sensory innervation to the nasal cavity

Answer 34

nasopalatine and nasociliary nerve

Question 35

What is the nasopalatine nerve a branch of

Answer 35

Maxillary nerve

Question 36

What is the nasociliary nerve a branch of

Answer 36

Ophthalmic nerve

Question 37

What nerve supplies the anterosuperior section of the nasal cavity

Answer 37

nasociliary nerve (branch of ophthalmic nerve - CN V1)

Question 38

What nerve supplies the inferoposterior section of the nasal cavity

Answer 38

nasopalatine nerve (branch of maxillary nerve - CN V2)