nasal cavity

Question 1

what are the functions of the nasal cavity

Answer 1

• sense of smell
• warms and moistens air
• helps speech

Question 2

what is the external nose made up of

Answer 2

mostly cartilaginous but also bone (nasal bone and maxilla)

Question 3

what is the vestibule in the nose

Answer 3

where the air flows into from the nostrils in the external nose

Question 4

how is the superior part of the nasal cavity different

Answer 4

its lined with olfactory mucus membrane - this contains receptors for the olfactory nerve so is where smell is sensed

Question 5

what is the roof of the nasal cavity

Answer 5

ethmoid bone (cribiform plate) and frontal bone

Question 6

what is the medial wall of the nasal cavity

Answer 6

the nasal septum - cartilaginous and also bony (ethmoid, vomor bone and sphenoid bone)

Question 7

what is the lateral wall of the nasal cavity

Answer 7

maxilla

Question 8

what is the floor of the nasal cavity

Answer 8

hard palate

Question 9

what happens to the movement of air when it enters the nasal cavity

Answer 9

it slows down

Question 10

what causes a slower movement of air in the nasal cavity

Answer 10

• movement into a bigger area

- turbulent air flow set up by the conchae

Question 11

what are the conchae in the nasal cavities

Answer 11

bony projections lined by the mucus membrane

Question 12

what are the spaces between the conchae called

Answer 12

meatus

Question 13

what epithelia lines the nasal cavity

Answer 13

pseudo stratified columnar ciliated

Question 14

what do the conchae in the nose do

Answer 14

• slows air down by creating turbulent blood flow

- increases the SA of the nasal cavity

Question 15

what sinuses drain into the nasal cavity and where in the cavity do they drain

Answer 15

• paranasal and nasolacrimal duct

- drain into the metauses

Question 16

what are the role of the sinuses

Answer 16

humidify and warm inspired air

reduce the weight of the skull

Question 17

what is the innervation to the paranasal sinuses

Answer 17

frontal, ethmoid and sphenoid = ophthalmic

maxillary = maxillary

Question 18

what are the names of the 4 paranasal sinuses

Answer 18

frontal, ethmoid, sphenoid and maxillary

Question 19

why does sinusitis most commonly occur in the maxillary sinus

Answer 19

as the drainage is higher up in the sinus wall, making it harder to drain into the nasal cavity so stasis can occur easily

Question 20

why does sinusitis involving the maxillary sinus cause tooth pain

Answer 20

the teeth and the maxillary sinus share a nerve supply (maxillary)

Question 21

where can infection in the ethmoid sinuses potentially spread to

Answer 21

orbits

Question 22

what nerves supply sensation to the nose

Answer 22

maxillary and ophthalmic branches of the trigeminal nerve

Question 23

where is the blood supply to the nose from

Answer 23

ophthalmic and maxillary arteries

Question 24

what is the most common type of nose bleed

Answer 24

anterior nose bleed - where the anatomoses in the cartilage of the nasal septum bleed

Question 25

what blood vessel causes posterior nose bleeds

Answer 25

sphenopalatine artery

Question 26

where does the venous drainage of the nose go

Answer 26

pterygoid plexus - cavernous sinus - facial vein

Question 27

how can a basilar skull fracture cause CSF leakage from the nose

Answer 27

can damage the crista Galli - the falx cerebri is attached to this so can rip the dura and cause CSF to fall into the nasal cavity

Question 28

what is a septal haematoma

Answer 28

where trauma to the nose separates the perichondrium overlying the cartilage of the nasal septum and blood accumulates in this space

Question 29

what happens to an untreated haematoma

Answer 29

saddle deformity due to avascular necrosis

Question 30

what are nasal polyps

Answer 30

benign growths in the nasal cavity from the mucosa

Question 31

what symptoms do nasal polyps give

Answer 31

reduced smell, reduced taste, watery rhinorrhoea, blocked nose

Question 32

what is rhinitis

Answer 32

inflammation of the nasal mucosal lining

Question 33

what is sinusitis

Answer 33

inflammation of the lining of the sinus

Question 34

how does an infection in the nasal cavity cause sinusitis

Answer 34

the infection causes reduced ciliary function, mucosal oedema and increased nasal secretions - this impedes drainage of the sinuses so theres stasis leading to infection