8. nose, nasal cavity (lecture) 2 Flashcards
what is the nasal cavity lined with?
olfactory mucous membrane
olfaction = smell
what is respiratory mucous membrane?
pseudostratified columnar ciliated epithelium
function of respiratory mucous membrane?
- filters (mucous / cilia)
- humidifies (watery secretions)
- warms (rich blood supply)
where does nasal cavity receives drainage from?
paranasal sinuses (into middle meatus first) nasolacrimal duct (drains eye into inferior meatus first)
what are conchae also known as?
turbinates
which cranial nerve carries general sensation from the nasal cavity?
trigeminal (V1, V2)
which cranial nerve carries specific sensation to the nasal cavity?
olfactory
purely sensory: smell
what are nasal polyps?
flesh, BENIGN swellings arising from nasal MUCOSA
what do nasal polyps usually affect?
both sides of nasal cavity
how do nasal polys appear?
pale or yellow in appearance
OR
fleshy and reddened
which age group do nasal polyps normally affect?
typically > 40 years
what are symptoms of nasal polyps?
- blocked nose and watery rhinorrhoea (CSF)
- post nasal drip
- decreased smell and reduced taste
how does nasal poly suggest tumour?
unilateral polyp +/- blood-tinged secretion may suggest tumour
how can nasal polyp result in post nasal drip?
increased nasal secretions drips down the back, gets a tickling feeling at the back of throat (drains to posterior nasal cavity rather than front of nose) - causes cough
what is rhinitis?
inflammation of the nasal mucosal lining
what are symptoms of rhinitis?
- nasal congestion
- rhinorrhoea (runny nose)
- sneezing
- nasal irritation
- postnasal drip
what are common causes of rhinitis?
- simple acute infective rhinitis (viral - common cold)
2. allergic rhinitis
what can foreign body in the nostril cause?
smelly and blood stained discharge
how does discharge of rhinitis normally present?
both nostrils, NOT usually blood stained
what is key to allow for warming and humidification of inspired air in nasal cavity?
rich blood supply
what does rich blood supply to nasal cavity result in?
nasal mucosa is susceptible to injury and bleeding
where does arterial supply of medial and lateral walls of nasal cavities arise from?
branches of OPHTHALMIC artery and branches of maxillary artery
what do branches of ophthalmic artery and branches of maxillary artery form?
a point of arterial anastomoses in anterior septum (Kiesselbach’s / little’s area)
where is the most common source of bleeding in epistaxis?
in Kiesselbach’s / Little’s area
anastomoses in anterior septum of ophthalmic and maxillary artery
where does venous drainage from the nasal cavity drain into?
cavernous sinus,
facial vein,
pterygoid plexus
what are the 5 arteries which supply the nose?
- anterior ethmoid
- posterior ethmoid
- sphenopalatine
- greater palatine
- superior labial
what are branches of the ophthalmic artery which supply the nose?
anterior and posterior ethmoid arteries
what is sphenopalatine artery a branch of?
maxillary artery which supplies the nose
where do 5-10% of nose bleeds come from?
sphenopalatine artery (posterior part of nose) - much more difficult to stop bleeding - too far into nasal cavity + in bony nasal cavity
where do 90% of nose-bleeds come from?
Kisselbach’s area
what are you pinching in nose-bleeds?
Kisselbach’s plexus - just in front of bony nasal (bridge)
where does the nasal arteries anastomose?
Kisselbach’s plexus
