10) Anatomy of Nose

Question 1

What are the functions of the nose?

Answer 1

Sense of smell 
Route for inspired air 
Filters air (removes particles by trapping in nasal hair or mucus)
Moistens and warms air 
Resonating chamber for speech

Question 2

What gives the external nose shape?

Answer 2

Hyaline cartilage (located anteriorly)

Question 3

Describe the features of the external nose:

Answer 3

Root (top)
Bridge (below root)
Tip/apex

Question 4

What bones form the root of the nose?

Answer 4

Nasal bone and frontal process of maxilla

Question 5

What is the nose susceptible to and why?

Answer 5

Fractures and septal deviation due to prominent position

Question 6

Where does the nasal cavity run?

Answer 6

Nostrils to posterior nasal aperture (choana)

Question 7

What is posterior to the nasal cavity?

Answer 7

Nasopharynx and Eustachian tube

Question 8

What forms the lateral wall of the nasal cavity?

Answer 8

Maxilla and inferior concha

Question 9

What forms the medial wall of the nasal cavity?

Answer 9

Septal cartilage, perpendicular plate of ethmoid and vomer

Question 10

What forms the floor of the nasal cavity?

Answer 10

Hard palate (maxilla and palatine) and soft palate

Question 11

What forms the roof of the nasal cavity?

Answer 11

Nasal, frontal, ethmoid and sphenoid

Question 12

What is the path of CSF in CSF rhinorrhoea?

Answer 12

Crista gala perforates meninges, CSF leaks through cribriform plate

Question 13

What is a septal haematoma?

Answer 13

Trauma to nose leads to buckling of septum and shearing of BVs causing blood to accumulate between perichondrium and cartilage

Question 14

What can occur if a septal haematoma is left untreated?

Answer 14

Avascular necrosis of cartilaginous septum and saddling of nasal dorsum
Also, infection leading to septal abscess

Question 15

What is the function of the concha on the lateral wall of nasal cavity?

Answer 15

Slow airflow and increase SA for humidification and warming of air

Question 16

What is the relevance of the spheno-ethmoidal recess?

Answer 16

Where some sinuses drain into nasal cavity

Question 17

What is the majority of epithelium of nasal cavity?

Answer 17

Pseudostratified columnar ciliated epithelium

Question 18

Where does the nasolacrimal duct drain into the nasal cavity?

Answer 18

Inferior meatus

Question 19

How does the epithelium of the nasal cavity carry out functions of the nose?

Answer 19

Filters - mucus and cilia
Warms - rich blood supply
Humidifies - watery secretions

Question 20

What are nasal polyps?

Answer 20

Fleshy, benign swellings arising from nasal mucosa, usually both sides
Greater than 40 years

Question 21

What are the symptoms of nasal polyps?

Answer 21

Blocked nose
Watery rhinorrhoea
Post nasal drip
Decreased smell and taste

Question 22

How does a nasal tumour present?

Answer 22

Unilateral polyp with blood tinged secretion

Question 23

What is rhinitis?

Answer 23

Inflamm of nasal mucosa lining

Question 24

What are the symptoms of rhinitis?

Answer 24

Nasal congestion
Rhinorrhoea
Sneezing
Irritation 
Post nasal drip

Question 25

What are the causes of rhinitis?

Answer 25

Acute infective rhinitis, allergic rhinitis

Question 26

Describe the blood supply to the nasal cavity:

Answer 26

Branches of ophthalmic artery (ICA) - ant and pos ethmoidal | Branch of maxillary artery (ECA) - sphenopalantine (posterior septum)

Question 27

What is the clinical relevance of Kiesselbach's area?

Answer 27

Where anastomoses occur, 90% of nose bleeds from here

Question 28

Why are nose bleeds from sphenopalantine artery worse?

Answer 28

Hard to stop as posterior and blood is at higher pressure

Question 29

What is the venous drainage of the nasal cavity?

Answer 29

Cavernous sinus, facial vein and pterygoid plexus

Question 30

Name the paranasal sinuses:

Answer 30

Frontal, ethmoid, sphenoid and maxillary

Question 31

What are the paranasal sinuses?

Answer 31

Air filled spaces lined with respiratory mucosa

Question 32

What is the function of the paranasal sinuses?

Answer 32

Help humidify and warm air, lighten skull

Question 33

How do the sinuses drain into the nasal cavity?

Answer 33

Via ostia, most into middle meatus

Question 34

What can cause sinusitis? | Where is it most likely?

Answer 34

Infections spreading from nasal cavity Obstruction of drainage Maxillary Sinus

Question 35

What are some important anatomical relations to the sinuses?

Answer 35

Orbit and anterior cranial fossa (frontal and ethmoidal) | Roots of upper teeth (maxillary)

Question 36

What is acute sinusitis?

Answer 36

Acute inflammation of lining of sinus lasting less than 4 weeks Commonly infective or secondary to cold

Question 37

Describe the pathophysiology of acute sinusitis:

Answer 37

Infection leads to reduced ciliary function, mucosal oedema and increased nasal secretions. This impedes drainage and stagnant secretions are breeding ground for bacteria

Question 38

What are the symptoms of acute sinusitis?

Answer 38

Non-resolving cold Pyrexia Rhinorrhoea with discharge Headache/facial pain in area of sinus (worse leaning forward)

Question 39

What conditions can increase the risk of sinusitis?

Answer 39

Conditions blocking ostia e.g. polyps or deviated septum | Dental infection

Question 40

What is the treatment for sinusitis?

Answer 40

Self limiting, but may need antibiotics

Question 41

What is a complication of sinusitis?

Answer 41

Orbital cellulitis

Question 42

What is the nerve supply to the nasal cavity and sinuses?

Answer 42

Antero-superior part of cavity and most sinuses - ophthalmic nerve (CN Va) Postero-inferior part and maxillary sinus - maxillary nerve (CN Vb)

Question 43

What is epistaxis and how can it be self-treated?

Answer 43

Nose bleed, pinch nose in front of bony bridge

Question 44

What can cause nose bleeds?

Answer 44

Spontaneous, minor trauma, abnormal coagulation or CT disorders

Question 45

What is the treatment for nose bleeds if compression fails?

Answer 45

Cauterise Anterior packing or nasal tampons Posterior packing Surgery e.g. ligation