Nasal cavities and Paranasal sinuses Flashcards
What are 5 functions of the nasal cavity?
Acts as a patent conduit for air to be transported to the nasopharynx Filters air of particulate material Humidifies air Warms inspired air in the nasal passage Sense of smell
What are vibrissae?
Small hairs
What are the 7 parts of the external nose (surface)?
Root Dorsum Tip Ala Nostril/Nares Septum Philtrum
What 7 bones are involved in the nose?
Frontal Ethmoid Nasal Inferior nasal concha Maxilla Perpendicular plate of the ethmoid bone Vomer
What is the crista galli?
Upward part of the ethmoid bone that seperates the two hemispheres of the brain
How many concha are there?
3
Where are the concha found?
Lateral wall of nasal cavities
Which concha is a also a bone?
Inferior concha
How many Le Fort fractures are there?
3
What can Le fort fractures disrupt?
Cribriform plate of ethmoid
What can result from Le fort fractures?
Anosmia
Infection
What is Anosmia?
Loss of smell
What 2 things are involved in the nasal mucosa?
Nasal vestibule
Nasal cavity
What type of tissue is the nasal vestibule?
Stratified squamous eptihelium
What type of tissue is in the nasal cavity?
Respiratory epithelium
Olfactory epithelium
What is olfaction?
Sense of smell
What nerve is the olfactory nerve?
CN 1
What type of nerve is olfactory?
Special sensory
What is the olfactory pathway?
Receptor cells in the olfactory epithelium Pass up through cribriform plate Synapse with olfactory bulb Then neurons pass along olfactory tract To temporal lobe and olfactory
What is the innervation of the nasal cavity?
Top portion: CN V1
Bottom portion: CN V2
What bones are involved in the medial wall of the nasal cavity (septum)?
Perpendicular plate of ethmoid
Septal cartilage
Vomer
What bones are involved in the lateral wall of the nasal cavity?
Lateral cartilage
Maxilla
Palantine
S,M,I concha
Where is the olfactory bulb in relation to the nose?
Above the nasal cavity
What is the origin of the anterior ethmoidal nerve?
Nasociliary
CN V1
What does the anterior ethmoidal nerve pass through?
Anterior ethmoidal foramen
What is the nasopalatine nerve a branch of?
CN V2
What does the nasopalatine nerve pass through?
Sphenopalatine foramen
What arteries supply the lateral nasal wall?
Anterior ethmidal artery Posterior ethmoidal artery Sphenopalatine artery Greater palatine artery Lateral nasal artery
What is Kiesselbach’s (Little’s) area?
Site where anastomosis between the arterial contributions
Where is Kiesselbach’s area located?
Anteroinferiorly on nasal septum
What can irritation of kiesselbach’s area lead to?
Epistaxis
Nose bleed
What is the name of the space below each nasal concha?
Meatus
Label this diagram
INSERT
What are concha often referred to as?
Turbinates
What do concha do and what does this allow?
Causes turbulent airflow through the nasal cavity
Increases opportunity for humidifying, warming and filtering air
How can airflow through the nose be impacted?
Engorgement of the nasal mucosa
How often does the side of nasal mucosa engorgement swap?
Every 1-5 hours
How many paranasal sinuses does the body have?
4 pairs (bilateral)
What are the 4 paranasal sinuses called?
Frontal sinuses
Ethmoidal air cells
Maxillary sinuses
Sphenoid sinuses
What lines each sinus?
Respiratory epithelium
Where does the sphenoid sinus drain?
Sphenoethmoidal recess
Where do the posterior ethmoidal air cells drain?
Superior meatus
What drains into the semilunar hiatus of the middle meatus?
Frontal sinus
Maxillary sinus
Anterior ethmoidal air cells
What drains into the ethmoidal bulla of the middle meatus?
Middle ethmoidal air cells
What drains into the inferior meatus?
Nasolacrimal duct
How does lacrimal fluid drain?
Inferomedially to the nasolacrimal duct which drains into the inferior meatus
What is sinusitis?
Inflammation of the mucosa in 1 or more of the paranasal sinuses
What are the 3 subtypes off sinusitis?
Acute
Sub chronic
Chronic
What direction do the cilia of respiratory mucosa waft towards?
Ostia
What can a viral URTI cause?
Swelling of mucosa, reducing diameter of ostia
What can fill sinuses causing pressure to build?
Infected mucous
Where can pain from sinusitis be referred?
Teeth
Which sinus is predisposed to infection?
Maxillary
Why is the maxillary sinus predisposed to infection?
Ostium of maxillary sinus is located superiorly in relation to its cavity
Cilia must work against gravity
What is an oro-antral fistula?
A communication between maxillary sinus and tooth socket
