7) The Nose

Question 1

What is the external nose comprised of?

Answer 1

Bony component
Predominantly cartilaginous
Nostrils bounded laterally by alae
Skin, extends into vestibule

Question 2

Which bones make up the bony part of the nose?

Answer 2

Nasal bones
Maxillae frontal processes
Frontal bone (nasal part & nasal spine)

Question 3

How many cartilages make up the cartilaginous portion of the nose?

Answer 3

2 Lateral cartilages
2 Alar cartilages
1 Septal cartilage

Question 4

How is the nasal septum comprised?

Answer 4

Anterior portion - Cartilaginous
Middle portion - Perpendicular plate of Ethmoid bone
Posterior portion - Vomer

Question 5

Why are nasal fractures the most common facial fractures?

Answer 5

Exposed organ
History of force to face, deformity
Complications - septal haematoma

Question 6

What components make up the nasal cavity?

Answer 6

Nostrils
Chonchae (turbinates)
Mucosal lining (except for vestibule)

Question 7

How many conchae are there in the nasal cavity?

Answer 7

Superior nasal conchae
Middle nasal conchae
Inferior nasal conchae

forming 5 passages (recesses/meatus)

Question 8

What are the 5 passages in the nasal cavity?

Answer 8

Spheno-ethmoidal recess
Superior meatus
Middle meatus
Inferior meatus
Hard palate

Question 9

How is the spheno-ethmoidal recess modified for olfaction?

Answer 9

Lining epithelium of mucous membrane

Axonal processes of olfactory cell pass through cribriform plate, penetrate meninges & enter olfactory bulb

Question 10

Name the openings in the nasal cavity

Answer 10

Cribriform plate (CNI)
Sphenopalatine foramen
Incisive foramen
Foramen cecum (nasal veins)

Question 11

What is the arterial supply to the nasal cavity?

Answer 11

Branches of:
Ophthalmic artery (ICA)
Maxillary & Facial arteries (ECA)

Question 12

What is Kiesselbach’s/Little’s area of the nasal cavity?

Answer 12

Rich anastomoses on anterior part of septum of nasal cavity (between vestibular & mucosal lining)
Lots of capillaries - extensive blood supply

Question 13

Which area of the nose causes profuse bleeding during nose bleeds?

Answer 13

Kiesselbach’s/Little’s area

Question 14

What is epistaxis?

Answer 14

Bleeding from the nose (nose bleed)
Very common
Anterior bleeds 90%
Posterior bleeds - sphenopalatine artery

Question 15

Describe the venous drainage of the nose

Answer 15

Submucosal venous plexus drains into:

• Cavernous sinus
• Facial vein
• Pterygoid plexus

Question 16

Which nerves innervate the nasal cavity?

Answer 16

Olfactory (CNI) - smell
Maxillary (CNVii) & Nasopalatine nerve - posteroinferior nasal mucosa
Ophthalmic (CNVi) & Ant. + Post. Ethmoidal nerves - anterosuperior nasal mucosa
External nasal (CN Vi) & Infraorbital (CN Vii) - External nose

Question 17

What types of epithelium can be found in the nasal cavity?

Answer 17

Respiratory: pseudostratified columnar cililated + goblet cells
Olfactory: Olfactory cells & receptors

Question 18

What are the 4 paranasal sinuses?

Answer 18

Frontal
Ethmoidal
Sphenoid
Maxillary

Question 19

Where do the frontal sinuses drain?

Answer 19

Frontonasal duct into ethmoidal infundibulum

to Middle nasal recess

Question 20

Where do the ethmoidal sinuses drain?

Answer 20

Middle nasal recess (anterior & middle ethmoidal cells)

Superior nasal recess (posterior ethmoidal cells)

Question 21

Where do the sphenoidal sinuses drain?

Answer 21

Sphenoethmoidal recess

Question 22

Where do the maxillary sinuses drain?

Answer 22

Maxillary ostium to middle nasal recess via semilunar hiatus

Question 23

Where may infections of the nasal cavity spread?

Answer 23

Anterior cranial fossa via cribriform plate
Paranasal sinuses via openings in nasal cavity
Lacrimal apparatus & conjunctiva via opening of nasolacrimal duct
Middle ear via eustachian tube

Question 24

What is rhinitis?

Answer 24

Inflammation of the nasal mucosa
swelling & increased volume of secretion
Causes:
 - infective (viral) adeno/rhinovirus, RSV
 - allergic
 - nasal polyps

Question 25

What is sinusitis?

Answer 25

Inflammation of mucosal lining of sinues
Acute 7-30 days, Chronic >90 days
Infection: Viral + bacterial, Strep pneum. Haem. inf

Question 26

What may happen if there is an ethmoidal sinus air cell infection?

Answer 26

Break through medial wall of orbit
Proximity to optic canal, optic nerve & ophthalmic artery
Visual disorders

Question 27

What happens when the maxillary sinuses become infected?

Answer 27

Most commonly infected
Small ostia, located high up obstructed
Sinuses cannot drain when head erect until full
Must lie on side

Question 28

What is the relationship between the maxillary teeth and maxillary sinus?

Answer 28

3 maxillary molar teeth close to floor of maxillary sinus
Removal, fracture of root may enter sinus
Communication between oral cavity and maxillary sinus
Infection
(superior alveolar nerves)