The Nose Flashcards
What are the two components of the external nose?
Bony part - located superiorly (nasal bones, maxillae and frontal bone)
Cartilaginous part - located inferiorly (2 lateral cartilages, two alar cartilages and 1 septal cartilage)
What is a saddle nose deformity?
Occurs primarily as a result of nasal trauma, whereby septal support to the nose is lost and the middle part of the nose appears sunken
Either as a result of direct damage to the septal bone or cartilage or a consequence of nasal septal haematoma (avascular necrosis)`
Describe the venous drainage of the nose
Drains into facial vein and cavernous sinus
as CS lies within cranial cavity, infections can spread from nasal area to brain
What provides sensory innervation to the external nose?
Trigeminal (CN V)
What are the four functions of the nasal cavity?
1) Warms and humidifies inspired air
2) Removes and traps pathogens/debris
3) Carries smell
4) Drains and clears paranasal sinuses and lacrimal ducts
What are the three divisions of the nasal cavity?
1) Vestibule
2) Respiratory region
3) Olfactory region (apex)
What are nasal conchae?
Curved shelves of bone that project out of the lateral walls of the nasal cavity
How many nasal conchae are there?
3 - inferior, middle and superior
What are meatuses?
The four pathways for the air to flow in the nasal cavity, created by the conchae
What are the meatuses in the nasal cavity?
Inferior meatus - between inferior concha and nasal floor
Middle meatus - between inferior and middle concha
Superior meatus - between middle and sperior concha
Spheno-ethmoidal recess - superiorly and posteriorly to superior concha
What is the function of the nasal conchae?
Increase surface area of nasal cavity to increase the amount of inspired air that can come into contact with the cavity walls
Make airflow slow and turbulent, so that the air spends longer in the nasal cavity to be humidified
Where is the most common location of epistaxis?
Anterior third of the nasal cavity - kiesselbach area
What are the paransal sinuses?
Frontal, Ethmoid, sphenoid, maxillary
Describe the innervation to paranasal sinuses
Frontal, ethmoid, sphenoid - CN Va
Maxillary - CN Vb
