The Nasal Cavity and Paranasal Air Sinuses Flashcards
What are the paranasal air sinuses?
Air gilled spaceds of facial bones
What kind of epithelium forms the respiratory mucosa which lines most of the nasal cavity?
Pseudostratified columnar ciliated epithelium
What is the roof of the nasal cavity lined by?
Olfactory mucosa
Which cranial nerve, responsible for the sense of smell, innervates this mucosa?
Olfactory (cranial nerve 1)
Which plate of bone lying on the roof of the cranial cavity do axons of this nerve pass through to enter into the cranial cavity?
Cribiform plate of the ethmoid bone
Crista galli
What are the 3 lateral wall projections called?
Conchae
What is the space inferior to each concha called?
Meatus
What is the name given to the space above the superior concha?
Sphenoethmoidal recess
The inferior concha is a separate bone. What bone are the superior and middle conchae parts of?
Perpendicular plate of ethmoid bone
The nose has a rich arterial supply from what?
Branches of the ophthalmic artery (itself a branch of the ICA) and also branches of the ECA.
What is venous drainage of the nose done by?
Venous plexus
What implications does this rich vascular supply of the nose have for a common clinical condition?
Commonly get nose bleeds- Epistaxis
This is Littes Area
What opens into the meatus?
A number of structures including opening of paranasal air sinuses and the nasolacrimal duct open into the meatuses
What are the paranasal air sinuses?
Air filled extensions of the nasal cavity
What are the functions of the paranasal air sinuses?
Lighten weight of the head
Increase resonance of the voice
Respiratory mucosa similar to and continuous with the lining of the nasal cavity lines the paranasal air sinuses. What is the clinical significance of this fact?
Respiratory Infections can easily spread through and infect sinuses.
What open into the spehnoid ethmoidal recess?
Sphenoid sinus
What open into the superior meatus?
Posterior ethmoidal air cells
What open into the middle meatus?
Maxillary sinus
Frontal sinus
Anterior ethmoidal air cells
Middle ethmoidal air cells
What open into the inferior meatus?
Nasolacrimal duct
Why is it essential that sinuses can drain freely into nasal cavity?
Due to it being lined by secretory mucosa
What sinus has its opening not at its most inferior part and therefore does not drain well?
Macxillary sinus
What air sinus has their floor indented with tooth sockets?
Maxillary sinus
What is sinus inflammation called?
Sinusitis
What can sinusitis result iN?
Blockage of the sinus opening into the nasal cavity subsequently resulting in severe sinus pain
What is the pain sensation for sinusitis carried by?
Braches of the trigeminal nerve innervating the sinus
Name the branches of CN V that innervate the following air sinuses:
Frontal air sinus: CNV1
Maxillary air sinus: CNV2
Spehnoid air sinus: CNV1 and V2
Ethmoidal air cells: CNV2
