Nasal Cavity

Question 1

describe the nasal cavities

Answer 1

paired structures with left & right nasal cavities separated by nasal septum

Question 2

anterior apertures of the nasal cavities

Answer 2

the nares

Question 3

posterior apertures of nasal cavities

Answer 3

chonae which open up into the nasopharynx

Question 4

function of nasal cavities

Answer 4

olfactory receptors for smell
respiratory - filtration and humidifying inspired air
receives & eliminates secretions from paranasal sinuses & lacrimal ducts

Question 5

bones of the nasal cavity

Answer 5

nasal bones
frontal process of maxillae

Question 6

cartilage of the nasal cavity

Answer 6

septal cartilage
major & minor alar cartilages
these extend the nasal cavity beyond the skull, directing nares inferiorly

Question 7

muscles of nasal cavity

Answer 7

nasalis, depressor septi nasai, levator labii superioris alaeque nasi

Question 8

what forms the floor of the nasal cavity

Answer 8

palatine process of maxillae & horizontal plate of palatine bones i.e. hard palate

Question 9

what is found in incisive canal

Answer 9

nasopalatine nerve & greater palatine artery

Question 10

what is the medial wall of the nasal cavity and what are its main components

Answer 10

medial wall = nasal septum
3 main components are:
1. septal cartilage
2. perpendicular plate of ethmoid bone
3. vomer

Question 11

lateral wall of nasal cavity formed from

Answer 11

nasal, ethmoid (superior & middle conchae), lacrimal, maxilla, inferior concha, palatine, sphenoid

Question 12

ethmoidal labyrinth projects what into nasal cavity

Answer 12

there is a L and R ethmoidal labyrinth which projects superior and middle conchae into nasal cavity

Question 13

what is found underlying each conchae

Answer 13

the corresponding meatus

Question 14

3 main nerves innervate nasal cavity

Answer 14

1. olfactory nerve CN I
2. ophthalmic nerve CN V1
3. maxillary nerve CN V2

Question 15

parasympathetic innervation of nasal cavity

Answer 15

• 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

Question 16

sympathetic innervation of nasal cavity

Answer 16

• 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

Question 17

ECA blood supply of nasal cavity

Answer 17

from maxillary artery; sphenopalatine, greater palatine (from oral cavity)
from facial artery; superior labial, lateral nasal

Question 18

ICA blood supply of nasal cavity

Answer 18

anterior and posterior ethmoidal arteries from ophthalmic

Question 19

venous drainage of nasal cavity

Answer 19

• 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

Question 20

what are paranasal sinuses

Answer 20

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.

Question 21

what is the ethmoid bulla

Answer 21

the largest anterior ethmoid cell

Question 22

what is the hiatus semilunaris

Answer 22

a crescent shaped groove in the lateral wall of the nasal cavity just inferior to the ethmoidal bulla

Question 23

hiatus semilunaris is the site of openings for

Answer 23

frontal, maxillary and anterior ethmoidal sinuses

Question 24

ethmoidal sinus drainage

Answer 24

anterior cells - drain into infundibulum in middle meatus
middle cells - drain into middle meatus at ethmoidal bulla
posterior cells - drain into superior meatus

Question 25

maxillary sinus drainage

Answer 25

drain into middle meatus at semilunar hiatus

Question 26

frontal sinus drainage

Answer 26

drains into middle meatus at infundibulum

Question 27

sphenoid sinus drainage

Answer 27

only sinus not to drain into lateral wall. drains into sphenoethmoidal recess superiorly and posteriorly in nasal cavity

Question 28

what is the infundibulum

Answer 28

continuation of frontonasal duct at anterior end of semilunar hiatus

Question 29

superior alveolar nerve innervates what

Answer 29

maxillary teeth and mucous membrane of maxillary sinuses