Nasal Cavity and Pterygopalatine fossa Flashcards
What are the three regions of the nose?
Nasal vestibules
Respiratory regions
olfactory regions
What bones make up the medial wall of the nasal cavity?
What makes up the roof of the nasal cavity?
- Nasal
- frontal
- cribiform plate
- sphenoid
What makes up the floor of the nasal cavity?
- palatine
- maxillary bones of the hard palate
What makes up the posterior boundary of the nasal cavity?
Chonana
What makes up the lateral wall of the nasal cavity?
- nasal
- lacrimal
- maxillary
- ethmoid
- palatine
- sphenoid
- inferior concha
What is the purpose of the three conchae?
- they increase the surface area in the nasal cavity
- helps us to warm and moisten the air
- the air twists through the recess underneath each concha like a turbine
What sinus is this?
Sphenoid sinus which drains into the sphenoethmoidal recess
What is this area?
Ehmoid bulla- middle ethmoid air cells
- see little dots, the little ethmoid air cells
What is this area beneath the ethmoid bulla?
- semilunar hiatus
- frontal sinus
- draining starts here then proceeds to the next two
- ant ethmoid air cells
- maxillary sinus
What meatus does the nasolacrimal duct drain into in the nasal cavity?
Inferior meatus
What is the clinical issue of this image?
- Deviation of the nasal septum
- causes:
- birth injury
- trauma (most common)
- Deviation may be so severe that it contacts the lateral wall and impairs your breathing
- causes:
- Rhinitis
- nasal mucosa become swollen and inflamed
- occurs during upper respiratory infections or allergic reaction
What are the four paranasal sinuses?
frontal
ethmoid
sphenoid
maxillary
What happens if you have a lot of inflammation in the paranasal sinuses?
- their drainage area is incredibly small
- if you have a lot of inflammation of mucous membranes the spaces starts to close off
- you get backed off
What nerve are the paranasal sinuses innervated by?
CN V
Why is the maxillary sinus not very effective at draining?
Because it drains superiorly
Why cant you have a sinus infection under the age of 7?
- because the sinuses arent really fully developed till the age of 7
What is the clinical issue of infection in ethmoidal cells?
- infection may break through the medial wall of the orbit
- may cause blindness or optic neuritis
What is a clinical issue with maxillary sinus?
- openings are located superiorly
- have to fill it alot to get it to drain
- when you lay down it drains
Describe the vasculature of the Nasal cavity
where do your anterior nose bleeds come from?
kiesselbach area
- an anastomsis of the nasal arteries
Where do your posterior nose bleeds come from?
Spehnopalatine artery
- drains in back of your mouth
- very uncommon
Where do the veins originating from opthalmic drain to?
Cavernous sinus
What does the triangle of danger mean to the nasal cavity?
- the veins from the nasal cavity can drain into the opthalmic vein which then drains into the cavernous sinus
- whats right next door to the cavernous sinus?
- THE BRAIN
- whats right next door to the cavernous sinus?
What are the four nerves that innervate the nasal cavity?
- olfactory nerve
- opthalamic V1
- maxillary V2
- Parasympathetic fibers from facial CN VII
What comes out of the pterygopalatine fossa?
What drains into the spenoethmoidal recess?
Sphenoid sinus
What drains into the superior meatus?
Posterior ethmoid air cells
What drains into the middle meatus-specifically the ethmoid bulla?
- Middle ethmoid air cells
What drains into the middle meatus- specifically the semilunar hiatus?
- frontal sinus
- anterior ethmoid air cells
- maxillary sinus
What drains into the inferior meatus?
Nasolacrimal duct
