Nasal Cavity Flashcards
describe the nasal cavities
paired structures with left & right nasal cavities separated by nasal septum
anterior apertures of the nasal cavities
the nares
posterior apertures of nasal cavities
chonae which open up into the nasopharynx
function of nasal cavities
olfactory receptors for smell
respiratory - filtration and humidifying inspired air
receives & eliminates secretions from paranasal sinuses & lacrimal ducts
bones of the nasal cavity
nasal bones
frontal process of maxillae
cartilage of the nasal cavity
septal cartilage
major & minor alar cartilages
these extend the nasal cavity beyond the skull, directing nares inferiorly
muscles of nasal cavity
nasalis, depressor septi nasai, levator labii superioris alaeque nasi
what forms the floor of the nasal cavity
palatine process of maxillae & horizontal plate of palatine bones i.e. hard palate
what is found in incisive canal
nasopalatine nerve & greater palatine artery
what is the medial wall of the nasal cavity and what are its main components
medial wall = nasal septum
3 main components are:
1. septal cartilage
2. perpendicular plate of ethmoid bone
3. vomer
lateral wall of nasal cavity formed from
nasal, ethmoid (superior & middle conchae), lacrimal, maxilla, inferior concha, palatine, sphenoid
ethmoidal labyrinth projects what into nasal cavity
there is a L and R ethmoidal labyrinth which projects superior and middle conchae into nasal cavity
what is found underlying each conchae
the corresponding meatus
3 main nerves innervate nasal cavity
- olfactory nerve CN I
- ophthalmic nerve CN V1
- maxillary nerve CN V2
parasympathetic innervation of nasal cavity
- axons from salvatory nucleus in brainstem are carried in greater petrosal nerve of CN VII to pterygopalatine ganglion in fossa
- post ganglionic axons are carried within branches of maxillary nerve
sympathetic innervation of nasal cavity
- axons from sympathetic trunk ascend in the internal carotid plexus and travel to pterygopalatine ganglion via deep petrosal nerve
- post ganglionic axons are also carried within branches of maxillary nerve
ECA blood supply of nasal cavity
from maxillary artery; sphenopalatine, greater palatine (from oral cavity)
from facial artery; superior labial, lateral nasal
ICA blood supply of nasal cavity
anterior and posterior ethmoidal arteries from ophthalmic
venous drainage of nasal cavity
- veins that follow maxillary artery drain to pterygoid plexus
- veins that follow facial artery drain to facial vein
- veins that follow ethmoidal arteries drain to ophthalmic vein and then cavernous sinus
what are paranasal sinuses
hollow cavities in bones within the skull lined with respiratory epithelium and open into nasal cavity. name based on which bone the are found within.
what is the ethmoid bulla
the largest anterior ethmoid cell
what is the hiatus semilunaris
a crescent shaped groove in the lateral wall of the nasal cavity just inferior to the ethmoidal bulla
hiatus semilunaris is the site of openings for
frontal, maxillary and anterior ethmoidal sinuses
ethmoidal sinus drainage
anterior cells - drain into infundibulum in middle meatus
middle cells - drain into middle meatus at ethmoidal bulla
posterior cells - drain into superior meatus
maxillary sinus drainage
drain into middle meatus at semilunar hiatus
frontal sinus drainage
drains into middle meatus at infundibulum
sphenoid sinus drainage
only sinus not to drain into lateral wall. drains into sphenoethmoidal recess superiorly and posteriorly in nasal cavity
what is the infundibulum
continuation of frontonasal duct at anterior end of semilunar hiatus
superior alveolar nerve innervates what
maxillary teeth and mucous membrane of maxillary sinuses
