Flashcards in H&N 8.1- the nose and paranasal sinus' Deck (53)
What are the main functions of the nose and nasal cavity?
-sense of smell
-route for air to get from the atmosphere into the lungs
-warms and humidifies inspired air
-filters inspired air (nasal hair and mucus)
-resonating chamber for speech
Why does your mouth get dry when you breath through your mouth?
It is not designed to warm and moisten the air like the nose is, so the air dries the mouth out.
What different structures are found in the nasal area?
What is the external nose made of?
cartilage and bone
What are the features of the external nose?
-the root (the bony part of the nose between the eyes)
-the bridge (the point at which the bone becomes cartilage)
What bones contribute to the external nose?
-frontal part of maxilla
Why are broken noses common?
The external nose is prominent so susceptible to trauma
How do you treat a broken nose?
-sometimes just left to heal on their own
-if there a deviated midline then surgery may be required to reallign the nose (only after swelling has gone down)
If someone has a broken nose, what must you bear in mind?
They will have experienced trauma, so there is also the risk of head injuries and neck injuries which need to be considered.
How can you further divide the nasal cavity?
-Vestibule- Just surrounding the external opening to the nasal cavity
-respiratory region- where the air travels, it is lined with pseudostratified clilliated mucosa which has goblet cells.
-olfactory region- located at apex, contains the olfactory receptors
What are the boundaries of the nasal cavity?
-superior- ethmoid bone (cribriform plate, crista galli), frontal bone, nasal bone, sphenoid bone
-lateral- maxilla and conchae
-medial- nasal septum
-floor- hard palate and soft palate
What is the nasal septum made from?
-the perpendicular plate of the cribriform plate
What makes up the hard palate?
-the palatine bones and the palatine process' of the maxilla.
What lies immediately superior to the nasal cavity?
What is the significance of this?
The anterior cranial fossa, which is attached to the crista galli via the falx cerebri,
Trauma to the nose can cause tearing of the falx cerebri, resulting in cerebral rhinorrhoea.
This could later result in an increased risk for meningitis/brain abcess.
What is a septal haematoma?
Can result after trauma to the nose, where there is a build up of blood between the perichondrium and cartilage.
What symptoms would someone with haematoma present with?
feelings of a blocked nose
change in the shape of the nose
What complications can arise from a septal haematoma and why do these develop?
The cartilage normally get's its blood supply from the overlying perichondrium, so when this is stripped away the cartilage undergoes avascular necrosis, and the septum can loose it's shape resulting in a concave appearance.
infection within the heamatoma due to stasis.
How would you treat a septal haematoma?
drain the blood from it and pack the nose, to push the 2 layers (perichondrium and cartilage) back together, to stop blood from building up between them again and to return blood supply to the cartilage.
What are conchae and what is their function?
bony projections on the lateral walls of the nasal cavity.
They act to increase surface area, to air with warming and humidifying inspired air and slowing the flow.
What is found beneath each conchae?
a corresponding meatus (here are where drainage from the paranasal sinus' and the nasolacrimal duct occurs)
What is the spheno-ethmoidal recess?
The area above the superior concha, therefore it is not a meatus.
The sphenoid sinus drains here.
What appearance does the nasal mucosa have?
you see this when looking up the nose, before the nasal mucosa you'll see skin coloured epithelia and hairs.
What membranes are found within the nasal cavity?
-olfactory mucus membrane (allow us to smell)
-respiratory mucus membrane (allow air to slow, warm and become humidified)
what nerve innervates the sensation of the nasal cavity?
The trigeminal nerve
(superior anterior-opthalmic branch)
(inferior posterior- maxillary branch)
What is a nasal polyp?
A benign fleshy swelling found within the nose which come from nasal mucosa.
-often occur in people >40
-pale/yellow in appearance or fleshy and redenned.
What symptoms might someone with a polyp complain of?
-a blocked nose
-decreased smell and reduced taste
-post-nasal drip (causing a tickly cough)
-rhinorrhoea (runny nose)
When might you be concerned about a polyp?
When it's unilateral / blood tinged/ in young people.
How could you determine between a concha or a polyp?
-a polyp will be paler in colour, mobile, and not hurt when touched.
-a concha will be pinker, be immobile and if poked will hurt.
What is rhinitis?
inflammation of the mucosal lining.