Nasal Cavity

Question 1

What are the anterior and the posterior apertures called?

Answer 1

Anterior = nares

Posterior = chonae

Question 2

What bones make up the nasal cavity?

Answer 2

Nasal
Ethmoid
Lacrimal
Maxilla
Palatine
Sphenoid

Question 3

What is septal deviation? How can it occur? What does this result in?

Answer 3

Where the nasal septum is displaced away from the midline

Birth defects or injury

Results in nasal cavity being obstructed on one side, causing symptoms such as snoring, difficulty breathing through nose and nosebleeds

Question 4

Why is the ethmoid bone important for the nasal cavity?

Answer 4

Has a left and right ethmoidal labyrinth with a single midline perpendicular plate and the cribiform plate

This forms the superior and middle nasal concha

Question 5

How many concha are there? What forms them? Whats their function

Answer 5

3 - superior, middle and inferior

Superior and middle formed by ethmoid bone

Inferior is a separate bone

Functions to increase surface area for air to be warmed and humidified. Also protects sinuses and olfactory cells

Question 6

Describe the cartilage of the nares

Answer 6

Minor alar cartilages are closest to the skull then the major alar cartilage forms the nares

Question 7

Describe the nervous innervation of the nasal cavity

Answer 7

CNI

CNV1 - anterior ethmoidal

CNV2 - anterior superior alveolar (nasal), infraorbital (nasal), nasopalatine and lateral nasal nerves

Question 8

Describe the autonomic nervous supply to the nose

Answer 8

Parasympathetic
- salvatory nucleus in brainstem are carried by greater petrosal nerve to the pterygopalatine ganglion
- post ganglionic axons travel within maxillary nerve

Sympathetic
- sympathetic trunk axons ascend and synapse with pterygopalatine ganglion via deep petrosal nerve
- also carried within maxillary nerve post ganglion

Question 9

Describe the arterial supply of the nasal cavity

Answer 9

ECA
- maxillary artery (sphenopalatine and greater palatine)
- facial artery (superior labial and lateral nasal)

ICA
- anterior and posterior ethmoidal arteries

Question 10

Describe the venous drainage of the nasal cavity

Answer 10

Pterygoid plexus veins from the maxillary arteries

Facial vein from facial arteries

Ophthalmic vein and cavernous sinus

Question 11

What are the paranasal sinuses? Whats their function?

Answer 11

Hollow cavities in bones within skull, lined with respiratory epithelium and open into nasal cavity

Lighten head, increase resonance of voice

Ethmoidal, maxillary, frontal, sphenoid