Nasal Cavity and Paranasal Sinuses Flashcards
(26 cards)
Why is it important for air to flow through the concha and meatuses?
creates more surface area, warms air, humidifies and filters air
Where does frontal sinus drain?
into infundibulum via the frontonasal duct into the semilunaris hiatus to the middle meatus
Where do anterior ethmoidal cells drain?
semilunaris hiatus
Where do middle ethmoidal air cells drain?
ethmoidal bulla
What makes the inferior surface of the semilunar hiatus?
uncinate process of ethmoidal bone
What are the 3 walls of the maxillary sinus?
superior = separates sinus from orbit Medial= separates sinus from nasal cavity Lateral = separates from infra temporal fossa
T/F Maxillary sinus cannot dip below the hard palate
F; can
Where does maxillary sinus drain?
middle meatus through the maxillary ostium
What does the nasal cavity share borders with?
oral cavity, anterior cranial fossa and orbit
What does the nasal cavity share neurovasculature with?
oral cavity
What might the roots of upper teeth be covered by in the maxillary sinus?
mucoperiosteum
Why is it bad if tooth root extends into maxillary sinus?
infection could spread, extraction may tear the membrane, produces fistula between mouth and maxillary sinus
What happens if fistula forms between mouth and maxillary sinus?
patient unable to blow cheeks out
- air from mouth escapes via fistula into sinus and nasal cavity
- no way to filter air
Where do posterior ethmoidal air cells drain?
superior meatus
Where does the nasolacrimal duct drain?
inferior meatus
Why can profuse bleeding occur in nasal cavity?
from extensive anastomoses in Kiesselbach’s area
What are the anastomoses in Kiesselbach’s area?
facial = superior labial and lateral nasal of facial arteries
Greater palatine a. via the incisive foramen/canal
How is epistaxisis controlled?
nasal packs or cautery
What are the orbital branches in the nasal cavity?
septal and lateral branches of anterior and posterior ethmoidal aa.
What are the facial artery branches?
alar branch of lateral nasal a and septal branch of nasal from superior labial artery
What are the maxillary artery branches?
lateral and septal branches of spenopalatine a, and greater palatine a
What is the special sensory n of the nasal cavity?
CN I
What are the general sensory n from?
CN V1 = nasociliary n
CN V2 = infraorbital, nasopalatine, ASA, PS lateral , PIL nn
What are the branches from nasociliary n?
external nasal br of anterior ethmoidal n, anterior ethmoidal n, septal branch of anterior ethmoidal n
