nose physiology (week 1)

Question 1

what is the functions of the nose?

Answer 1

help moisturise air

sense organ (has the olfactory apparatus)

immune - has mucus and IgA and IgE.

speech

Question 2

what is choanal atresia?

Answer 2

the failed recanalization of the nasal fossae during foetal development

neonates (new-borns) are only nasal breathers, so requires urgent surgical repair or else will suffocate

Question 3

what are paranasal sinuses and their function ?

Answer 3

air-filled and arise from nasal cavity

reduce the skull weight
humidification
vocal resonance
immune barrier (lined by respiratory mucosa
heat insulation
physical buffer (like crumple zone of a car)

Question 4

what bones and cartilages make up the nose?

Answer 4

nasal bone - 2 symmetrical

upper lateral cartilages - 2 symmetrical

lower lateral (alar) cartilages - 2 symmetrical

septal cartilage

Question 5

describe what happens in saddle nose deformity

Answer 5

result of nasal trauma

cartilage does not have its own blood supply so relies off surrounding tissues

saddle bump occurs and pushes perichondrium from the septal cartilage, stopping it getting blood supply

results in ischaemia and necrosis of the septum

Question 6

what arteries and veins supply the external nose?

Answer 6

skin of nose - supratrochlear and dorsal nasal arteries (branches of ophthalmic artery) and infraorbital artery (branch of maxillary artery)

septum and alar cartilages receive supply from the angular artery and lateral nasal artery

venous drainage via facial vein, then into IJV

Question 7

what is the danger triangle?

Answer 7

area from middle of eyes to both sides of the mouth

due to connections of cavernous sinus and ophthalmic veins means infection can spread rapidly

infections in cavernous sinus which can cause cavernous vein thrombosis.