Nose - Anatomy / Physiology

Question 1

what part of the nose is responsible for creating laminar flow of air ?

Answer 1

septum and turbinates

Question 2

why is the nasal airway important for neonates?

Answer 2

because they are obligate nasal breathers

Question 3

which congenital abnormality can occur in the nose in neonates?

Answer 3

choanal atresia

back of the nasal passage is blocked either by soft or bony tissue

Question 4

what is the mucosal lining of the nose?

Answer 4

anterior 1/3rd is stratified squamous

posterior 2/3rds is pseudo stratified columnar epithelium

Question 5

what nerve provides our sense of smell and where does it arise from?

Answer 5

olfactory nerve which arises from cribriform plate

Question 6

what provides aeration of the middle ear?

Answer 6

eustachian tube

Question 7

what are the functions of the sinuses and what are they?

Answer 7

frontal, ethmoid, sphenoid, maxillary

lightens the skull
protects crumpling zones from trauma
helps with vocal resonance
lined with same mucosa as the nose providing an immune barrier

Question 8

what are the external sub units of the nose?

Answer 8

glabella 
nasion 
dorsum 
supra tip 
tip
collumnella

Question 9

within the internal nose what forms the …

1. roof
2. lateral
3. floor
4. nasal septum

Answer 9

1. cribriform plate / skull base
2. turbinates
3. hard palate
4. bone - vomer and perpendicular plates of ethmoid & septal cartilage

Question 10

what is the clinical significance of breaking the nose?

Answer 10

you have to investigate whether the perpendicular plate of sphenoid bone isn’t broken as this can damage the cribriform plate resulting CSF leakage

Question 11

how does a septal haematoma form?

Answer 11

usually post trauma which results in lack of blood supply to the cartilage
tis results in septal necrosis and can lead to perforation

Question 12

what are the causes of a septal haematoma?

Answer 12

trauma

drugs - overuse of vasoconstrictors such as coccaine

Question 13

what type of tissue covers the turbinates and why?

Answer 13

erectile tissue
allows them to expand in response to temperature i.e. when its cold outside more air has to be humidified so the turbinates expand to humidify a greater volume of air

Question 14

what is the function of the turbinates?

Answer 14

humidify and warm air

Question 15

what is the name of the tear duct and where is it found and what does it pass through?

Answer 15

nasolacrimal duct

opens under inferior turbinate and passes through inferior meatus

Question 16

why do you get a runny nose when you cry?

Answer 16

the nasolacrimal duct (tear duct) opens up through the inferior turbinate into the nasal cavity

Question 17

where does each sinus open into and drain into?

Answer 17

frontal - lateral to middle turbinate and drains into middle meatus
maxillary - lateral to middle turbinate and drains into middle meatus
ethmoid - anterior to middle meatus and lateral to middle turbinate & posterior to superior and later to superior turbinate
sphenoid - drains to sphenoethmoidal recess and lies medial to superior turbinate

Question 18

which sinuses are termed as ‘honeycomb like’? and where do they drain?

Answer 18

ethmoid sinuses
anterior drains to middle meatus
posterior drains to superior meatus

Question 19

which nerve runs above the sphenoid sinus?

Answer 19

optic nerve

Question 20

what can result as a complication from severe sinusitis of the frontal sinuses?

Answer 20

pots puffy

swelling and oedema bulging out of the forehead

Question 21

what drains into the inferior meatus?

Answer 21

nasolacrimal duct

Question 22

what is the condition called when there is inflammation and infection that affects the nasal passageway and therefore paranasal sinuses?

Answer 22

rhino sinusitis

Question 23

what is the important relation with the maxillary sinus?

Answer 23

orbits

if infection spreads can cause orbital sepsis - affect eye sight

Question 24

what is the important relation with the frontal and sphenoid sinuses?

Answer 24

the cranial fossa

infection can spread causing meningitis or intracranial abscess

Question 25

whats is the clinical importance of the middle meatus ?

Answer 25

the frontal, maxillary and anterior sphenoid sinuses drain into the middle meatus, therefore if there is an infection in either of these sinuses it can spread through the middle meatus

Question 26

what are the treatments for sinusitis?

Answer 26

anti histamines
steroid nasal spray
antibiotics if infection
chronic - surgery to remove polyps or to open up sinus drainage pathway

Question 27

what are the risks of performing surgery for sinusitis?

Answer 27

lovely related structures;
damage to the lamina papyracea (orbital damage)
damage to skull base causing CSF leak

Question 28

what is the blood supply of the internal nose?

Answer 28

branches of internal carotid artery;

anterior and posterior ethmoid arteries via ophthalmic nerve V3

Question 29

what is the external blood supply of the nose?

Answer 29

external carotid artery
sphenopalatine artery via maxillary
greater palatine via maxillary
superior labial via facial

Question 30

what is the clinical relevance of littles area?

Answer 30

most common area which causes nose bleeds / epistaxis

Question 31

what arteries make up littles area?

Answer 31

anterior and posterior ethmoid arteries , sphenopalatine and superior labial artery

Question 32

what is the nerve supply of the nose?

Answer 32

trigeminal V1 and V2

parasympathetic = Vidian nerve (greater and deep petrosal)

Question 33

what equalises the pressure in the middle ear during swallowing?

Answer 33

the muscles of the soft palate is attached to eustachian tube and opens the tube during swallowing

Question 34

where in the post nasal space does adenomas commonly form and why?

Answer 34

waldeyers ring

area of lymphatic tissue

Question 35

what is the clinical significance of the fossa of Rosenmuller in the post nasal space?

Answer 35

contains the node of rouvier which is the first lymph nodes that nasopharyngeal carcinoma spreads to

Question 36

what is a sign of nasopharyngeal carcinoma?

Answer 36

one sided glue ear (otitis media with effusion)

Question 37

what arteries are part of the keisselbach’s plexus and why is this of clinical significance?

Answer 37

anterior and posterior ethmoidal arteries
greater palatine artery
sphenopalatine artery
superior labial artery

keisselbach’s plexus = littles area, most common source of epistaxis (nose bleeds)