nasal cavity

Question 1

main components of nasal cavity

Answer 1

bone, cartilage and muscle

Question 2

name bones of nose

Answer 2

nasal bones
frontal processes of maxillae

Question 3

name cartilage of nose

Answer 3

septal cartilage
major and minor alar cartilages

Question 4

name muscles of nose

Answer 4

nasalis
depressor septi nasi
levator labii superioris alaequae nasi

Question 5

name parts of floor of nasal cavity

Answer 5

hard palate - palatine process of maxilla & horizontal palate of palatine bones

Question 6

features of nasal floor

Answer 6

nares
incisive (nasopalatine) canals - contain nasopalatine nerve and greater palatine artery
nasal crest - ridge formed at connection of paired maxillae and palatine bones

Question 7

what makes up medial wall of nose

Answer 7

nasal septum:
septal cartilage
perpendicular plate of ethmoid bone
vomer

Question 8

what makes up roof of nasal cavity

Answer 8

highest point is cribiform plate of ethmoid bone
nasal bones
nasal spine of frontal bone
sphenoid bone

Question 9

outline ethmoid bone

Answer 9

left and right ethmoidal labryinth with a single midline cribiform plate
the plate has many foramina to allow the passage of olfactory nerves into nasal cavity
the labyrinth projects the superior and middle conchae

Question 10

what can a tumour in frontal lobe lead to

Answer 10

may cause. the brain and olfactory bulb to move, tearing the olfactory nerves. this can cause anosmia

Question 11

what may a fracture of cribiform plate cause

Answer 11

as the olfactory nerves are anchored by dura, if there is a fracture there can be a leakage of CSF down into nasal cavity - CSF rhinorrhoea

Question 12

what forms lateral wall of nasal cavity

Answer 12

ethmoid bone which forms superior and middle concha
inferior concha is its own bone

Question 13

what lies underneath the chonchas

Answer 13

meatus

Question 14

what provides blood supply to nasal cavity

Answer 14

external carotid: maxillary artery (sphenopalatine, greater palatine) & facial artery (superior labial, lateral nasal)

internal carotid/ opthalmic artery

anterior & posterior ethmoidal arteries - These vessels form many anastomoses, especially in the anterior septal region & this is an area in which nosebleeds can commonly occur

Question 15

what provides venous drainage from nasal cavity

Answer 15

veins tend to follow arteries
Veins that follow arteries of the maxillary artery drain into the pterygoid plexus
Veins that follow arteries of the facial artery drain into the facial vein
Veins that follow ethmoidal arteries drain into the ophthalmic vein & subsequently the cavernous sinus

Question 16

name the paranasal sinuses

Answer 16

frontal sinus
ethmoidal air cells
maxillary sinus
sphenoid sinus

Question 17

what are functions of paranasal sinuses

Answer 17

Hollow air-filled cavities
Increase surface area aiding efficient “air conditioning”
Lighten the skull
Add resonance to the voice

Question 18

what is the drainage point of ethmoidal air cells

Answer 18

Anterior cells drain into infundibulum in middle meatus
Middle cells drain into middle meatus at the ethmoidal bulla
Posterior cells drain into superior meatus

Question 19

where does maxillary sinus drain

Answer 19

Drains into the middle meatus at the semilunar hiatus

Question 20

where does frontal sinus drain

Answer 20

Drains into the middle meatus at the infundibulum

Question 21

where does sphenoid sinus drain

Answer 21

it drains into sphenoethmoidal recess superiorly and posteriorly in the nasal cavity