Head & Neck 1 - Nasal Cavity & Paranasal Sinuses

Question 1

which one of these bones DO NOT make up the external nose?
A: frontal bones
B: nasal bones
C: sphenoid bones
D: maxillary bones

Answer 1

C: sphenoid bones - external nose consists of frontal, nasal & maxillary bones

Question 2

what holds together the different cartilaginous components of the external nose?

Answer 2

fibrofatty tissue

Question 3

what are the anterior nares?

Answer 3

nostrils - anterior openings into nasal cavity

Question 4

what components make up the ROOF of the nasal cavity?

Answer 4

frontal & nasal bones
cribriform plate of ethmoid bone
sphenoid bone

Question 5

what components make up the FLOOR of the nasal cavity?

Answer 5

hard palate (formed by maxilla & palatine bony components)

Question 6

what bones form the hard palate?

Answer 6

palatine process of maxilla
horizontal plate of palatine bone

Question 7

what components make up the MEDIAL WALL of the nasal cavity?

Answer 7

septal cartilage (anterior)
perpendicular plate of ethmoid (superoposterior)
vomer (posteroinferior)

Question 8

what components make up the LATERAL WALL of the nasal cavity?

Answer 8

lacrimal bones
frontal process of maxilla
superior, middle & inferior conchae
perpendicular plate of palatine bone
pterygoid plate of sphenoid bone

Question 9

which one of the conchae is NOT part of the ethmoid bone?
A: superior concha
B: middle concha
C: inferior concha

Answer 9

C: inferior concha - is a separate bone

Question 10

which of the conchae IS part of the ethmoid bone? (2)
A: superior concha
B: middle concha
C: inferior concha

Answer 10

A & B: superior & middle conchae

Question 11

what external structure marks the medial wall of the nasal cavity?

Answer 11

nasal septum

Question 12

what two arteries give off branches that mainly supply the MEDIAL & LATERAL WALL of the nasal cavity?

Answer 12

internal carotid artery
external carotid artery

Question 13

what 6 arteries supply the medial & lateral walls of the nasal cavity? (from the artery they arise from too)

Answer 13

internal carotid artery
- anterior ethmoidal artery
- posterior ethmoidal artery

external carotid artery
- sphenopalatine artery
- greater palatine artery

facial artery (branch of ECA)
- superior labial artery
- lateral nasal artery

Question 14

what is the difference between the blood supply to the medial & lateral walls of the nasal cavity?

Answer 14

there isn’t one - both are supplied by the same branches of the internal & external carotid arteries

Question 15

what key structures does the lateral wall of the nasal cavity consist of?

Answer 15

nasal conchae (3) - superior, middle, inferior
nasal meati (3) - superior, middle, inferior

each nasal meatus is under its corresponding concha - e.g. superior nasal meatus is under the superior nasal concha

Question 16

what is the function of the nasal conchae?

Answer 16

1. increase surface area for efficient airflow into lungs
2. warming and humidifying air as it passes to the lungs - rich vascular supply in mucosal lining of nasal cavity

Question 17

what is the Kisselbach’s plexus?

Answer 17

network of 5 arteries in the nasal cavity
- anterior ethmoidal artery
- posterior ethmoidal artery
- sphenopalatine artery
- greater palatine artery
- superior labial artery

Question 18

what is epistaxis?

Answer 18

bleeding from the anterior part of the nasal cavity (nosebleed) - often originates from Kisselbach’s plexus

Question 19

what is the clinical significance of Kisselbach’s plexus?

Answer 19

often the origin of nosebleeds

Question 20

which of these arteries are NOT part of Kisselbach’s plexus?
A: anterior ethmoidal artery
B: lateral nasal artery
C: sphenopalatine artery
D: superior labial artery

Answer 20

B: lateral nasal artery

Question 21

what is the general sense innervation for the nasal cavity?

Answer 21

ophthalmic & maxillary divisions of the trigeminal nerve (CNV1 & 2)

Question 22

what is the special sense innervation for the nasal cavity?

Answer 22

olfactory nerve (CN1)

Question 23

what type of epithelium covers the majority of the nasal cavity? what area is the exception and what is it covered by instead?

Answer 23

majority of nasal cavity - ‘respiratory epithelium’/ pseudostratified columnar ciliated epithelium

nasal vestibule is the exception - covered by stratified squamous epithelium

Question 24

what is ‘respiratory epithelium’?

Answer 24

pseudostratified columnar ciliated epithelium
- appears to have multiple cell layers, but consists of a single layer
- has goblet cells which secrete mucus & ciliated cells sweep mucus away

Question 25

what are the 4 paranasal sinuses?

Answer 25

frontal ethmoidal sphenoidal maxillary (they're all paired!!)

Question 26

what are paranasal sinuses?

Answer 26

air-filled cavities connected to the lateral walls of the nasal cavity

Question 27

what type of epithelium are the paranasal sinuses lined by?

Answer 27

pseudostratified columnar ciliated epithelium

Question 28

what is the main source of blood supply to the paranasal sinuses? A: branches of the internal carotid artery B: branches of the facial artery C: branches of the external carotid artery D: branches of the common carotid artery

Answer 28

C: branches of the external carotid artery

Question 29

what cranial nerve innervates the paranasal sinuses? A: abducens nerve; CN6 B: facial nerve; CN7 C: trochlear nerve; CN4 D: trigeminal nerve; CN5

Answer 29

D: trigeminal nerve; CN5

Question 30

what are the functions of the paranasal sinuses?

Answer 30

1. lighten the skull (as air-filled cavities) 2. increase voice resonance 3. help with immune defence of the nasal cavity 4. humidify inspired air

Question 31

within what bone is the frontal sinus located?

Answer 31

within the frontal bone - superior to the orbit (eye socket)

Question 32

where are the ethmoidal air cells/sinus located?

Answer 32

within the ethmoidal bone - form part of the medial wall of the nasal cavity

Question 33

how many ethmoidal air cells are typically present within the ethmoidal bone?

Answer 33

3-18 - irregularly-shaped air-filled cavities, giving the ethmoid bone a honeycomb appearance

Question 34

what are the three subdivisions of the ethmoidal air cells?

Answer 34

anterior middle posterior

Question 35

where does the sphenoid sinus lie relative to the sella turcica (which houses the pituitary gland)? what does this mean clinically?

Answer 35

sphenoid sinus lies BELOW/INFERIOR to the sella turcica clinically means the pituitary gland can be surgically accessed via the nasal cavity and sphenoidal sinus (transsphenoidal surgery)

Question 36

where does the frontal sinus drain?

Answer 36

middle nasal meatus (via the frontonasal duct)

Question 37

where does the anterior ethmoidal sinus drain?

Answer 37

middle nasal meatus (via the frontonasal duct)

Question 38

where does the middle ethmoidal sinus drain?

Answer 38

middle nasal meatus (via ethmoid bulla)

Question 39

where does the posterior ethmoidal sinus drain?

Answer 39

(lateral wall of) superior nasal meatus

Question 40

where does the sphenoidal sinus drain?

Answer 40

sphenoethmoidal recess (superoposterior to superior nasal concha)

Question 41

where does the maxillary sinus drain?

Answer 41

middle nasal meatus (via the maxillary ostium)

Question 42

which is the largest of the paranasal sinuses?

Answer 42

maxillary sinus

Question 43

where is the maxillary sinus located?

Answer 43

within the maxilla inferior to the orbit (eye socket) superior to the upper teeth

Question 44

why is drainage of the maxillary sinus often difficult?

Answer 44

ostium (opening) of the maxillary sinus is higher than the sinus floor - makes its natural drainage against gravity difficult

Question 45

how does head positioning affect maxillary sinus drainage in individuals with sinusitis?

Answer 45

patients with maxillary sinusitis may feel relief when *tilting their head* - allows better alignment with gravity for drainage

Question 46

which of the ethmoidal sinuses DON'T drain into the middle meatus? where does it drain instead?

Answer 46

posterior ethmoidal sinus - drains into lateral wall of the superior nasal meatus

Question 47

which sinuses drain into the middle meatus? (4)

Answer 47

frontal sinus anterior ethmoidal sinus middle ethmoidal sinus maxillary sinus

Question 48

Which of the following sinuses drains into the sphenoethmoidal recess? A) Anterior ethmoidal sinus B) Posterior ethmoidal sinus C) Maxillary sinus D) Sphenoidal sinus

Answer 48

D) Sphenoidal sinus

Question 48

Which sinus drains into the superior meatus of the nasal cavity? A) Frontal sinus B) Maxillary sinus C) Sphenoidal sinus D) Posterior ethmoidal sinuses

Answer 48

D) Posterior ethmoidal sinuses

Question 49

The maxillary sinus drains into which of the following locations? A) Superior meatus B) Middle meatus C) Inferior meatus D) Sphenoethmoidal recess

Answer 49

B) Middle meatus

Question 50

The nasolacrimal duct drains into which part of the nasal cavity? A) Middle meatus B) Inferior meatus C) Superior meatus D) Sphenoethmoidal recess

Answer 50

B) Inferior meatus

Question 51

Which paranasal sinus can be used to surgically access the pituitary gland? A) Frontal B) Ethmoidal C) Sphenoidal D) Maxillary

Answer 51

C) Sphenoidal - pituitary gland lies inferior to the sphenoid sinus in the sella turcica; can access it through the nasal cavity