Anatomy and Physiology of the Nose

Question 1

What are the main functions of the nose?

Answer 1

Nasal airway
Olfaction (smell)
Immune
Speech

Question 2

What does the nose do to inspired air?

Answer 2

Warms and humidifies it

Question 3

After which surgeries may a patient need need to humidifier to prevent drying out of the lower airways?

Answer 3

Tracheostomy
Laryngectomy

Question 4

What in the function of the cilia on the walls of the nasal cavity?

Answer 4

Trap dust and harmful particles.

Question 5

Why do we smell?

Answer 5

For pleasure and to warn against danger e.g. fire

Question 6

How does smell link to taste?

Answer 6

While chewing, chemicals from food activate olfactory receptors to indentify food flavour.

Question 7

What is choanal atresia of the nose?

Answer 7

Failed recanalization of the nasal fossae during foetal development

Question 8

Why is choanal atresia an emergency in neonates?

Answer 8

They are obligate nasal breathers so will be unable to breathe.

Question 9

How is choanal atresia fixed?

Answer 9

Surgery

Question 10

How does the nose play a role in immunity?

Answer 10

Mucus consists of compounds which can neutralize antigens.

Question 11

Which immunoglobulins are found on the mucosal surfaces of the nose?

Answer 11

IgA
IgE

Question 12

What can reduce number of nasal cilia and changes mucus viscosity?

Answer 12

Smoking

Question 13

How does the nose affect speech?

Answer 13

Provides vocal resonance and nasal clicks

->if bunged up because of a cold, voice is thicker and less easily understood

Question 14

At which point does nasal flow turn from laminar to turbulent?

Answer 14

When it goes through the nasal valve

Question 15

Why is it important that nasal laminar flow turns into turbulent flow?

Answer 15

Decreases velocity so there is prolonged exposure to nasal mucosa

->this is probably to give more time to trap dust, neutralize pathogens, smell, etc.

Question 16

What are the paranasal sinuses?

Answer 16

Air filled cavities

Question 17

What is the function of paranasal sinuses?

Answer 17

Debated but suggested decreases weight of skull?
Possible heat insulation?
Humidification?

Question 18

What is meant by the dorsum of the nose?

Answer 18

Surface between root of nose and tip

Question 19

What is the name of the openings of the nose?

Answer 19

Nares

Question 20

What are the two nares separated by?

Answer 20

Columella

Question 21

There are two parts of the nasal skeleton- bone and cartilage. Describe the bones of the nasal skeleton.

Answer 21

Paired, symmetrical and oblong

Question 22

Name the two main paired cartilages of the nose.

Answer 22

Upper lateral cartilage
Lower lateral (alar) cartilage

Question 23

Which bones do the nasal bones articulate with:
1. superiorly
2. laterally

Answer 23

1. Frontal bones
2. Maxilla bones

Question 24

What are the two paired cartilages of the nose attached to and supported by?

Answer 24

Septal cartilage

Question 25

What is the most common facial fracture?

Answer 25

Nasal fracture

Question 26

What can a nasal fracture result in?

Answer 26

Permanent deformity

Question 27

How can a nasal fracture be corrected?

Answer 27

Via surgery but has to be quick before bone heals

Question 28

When assessing nasal injury, what trauma-related issue must you look out for?

Answer 28

Septal haematoma

Question 29

What can untreated septal haematoma result in?

Answer 29

Saddle nose deformity

Question 30

What is a septal haematoma?

Answer 30

Collection of blood between the perichondrium and cartilage of the nasal septum.

Question 31

What happens if the septal haematoma is not correctly drained?

Answer 31

Mucal perichondrium is not replaced onto cartilage leading to ischaemia and necrosis of septum.

Question 32

What does the saddle provide the nose with?

Answer 32

Support, therefore, in a saddle nose deformity, the support to the nose is lost.

Question 33

Where does the skin of the external nose receive blood from?

Answer 33

Supratrochlear and dorsal nasal arteries. Infraorbital artery.

Question 34

Which artery are the supratrochlear and dorsal nasal arteries branches of?

Answer 34

Ophthalmic artery

Question 35

Which artery is the infraorbital artery a branch of?

Answer 35

Maxillary artery

Question 36

Where do the septum and agar cartilages receive arterial blood from?

Answer 36

Angular artery Lateral nasal artery

Question 37

Which artery are the angular and lateral nasal artery branches of?

Answer 37

Facial artery

Question 38

Describe the venous drainage of the nose.

Answer 38

Drained by facial vain into internal jugular vein.

Question 39

Describe what is meant by the danger triangle of the nose.

Answer 39

Highly anastomotic venous system of nose allows retrograde spread of infection to the cavernous sinus via ophthalmic veins. Life and sight threatening.

Question 40

What are some of the clinical signs of Cavernous sinus thrombosis?

Answer 40

Ptosis (drooping of eyes) Chemosis (eye irritation) Cranial nerve palsies

Question 41

Which nerves are are danger of cranial nerve palsies in cavernous sinus thrombosis?

Answer 41

III- Oculomotor IV- Trochlear V- Trigeminal VI- Abducens

Question 42

What are some of the potential consequences of cavernous sinus thrombosis?

Answer 42

Papilledema (swelling of optic disc) Retinal haemorrhages Decreased visual acuity Blindness

Question 43

What may be present clinically in those with cavernous sinus thrombosis?

Answer 43

Fever Tachycardia Sepsis Headache w neck stiffness

Question 44

Which nerve is the innervation of the external nose derived from?

Answer 44

Trigeminal nerve

Question 45

Which nerve supplies motor innervation to the muscles of the nose?

Answer 45

Facial nerve

Question 46

Which nerves supply the skin of the dorsum of the nose, nasal alae and nasal vestibule?

Answer 46

Intertrochlear and external nasal nerves- both branches of the ophthalmic nerve.

Question 47

Which nerve supplies the lateral aspects of the nose?

Answer 47

Infraorbital nerve, branch of maxillary nerve

Question 48

What are the main two muscles of the nose?

Answer 48

Nasalis Procerus

Question 49

Which muscle covers the dorsum of the nose?

Answer 49

NasalisW

Question 50

Which muscle is a small pyramidal shape superior to the dorsum occupying the glabella(between eyebrows)?

Answer 50

Procerus

Question 51

What is the innervation of the nasalis muscle?

Answer 51

Buccinator branch of facial nerve

Question 52

What is the action of the nasalis muscle?

Answer 52

Alar part- depresses ala laterally, dilates nostrils Lateral part- wrinkles skin of dorsum

Question 53

What is the innervation of the procerus muscle?

Answer 53

Temporal, lower zygomatic or buccal branches of facial nerve.

Question 54

What is the action of the procerus muscle?

Answer 54

Depresses medial ends of eyebrows Wrinkles skin over glabella (between eyebrows) Creates frowning expression when exposed to bright light or eye irritants

Question 55

Name the three parts of the nasal cavity.

Answer 55

1. Vestibule 2. Respiratory region 3. Olfactory region

Question 56

What is the vestibule of the nose?

Answer 56

Entrance to nasal cavity, lined with hair bearing skin

Question 57

Describe the histology of the respiratory region of the nasal cavity.

Answer 57

Lined by ciliated pseudostratified epithelium with mucus secreting goblet cells.

Question 58

Describe the olfactory region of the nasal cavity.

Answer 58

Apex of nasal cavity, lined with olfactory cells w olfactory receptors.

Question 59

What does the nasal septum do?

Answer 59

Divides right and left nasal passages

Question 60

Name the three paired bony projections from the lateral nasal wall.

Answer 60

Turbinates/conchea 1. Superior turbinate 2. Middle turbinate 3. Posterior turbinate

Question 61

What does the presence of the three tubinates form?

Answer 61

Superior, middle and inferior meatus

Question 62

Why does the internal nose have a rich vascular supply?

Answer 62

Allows humidification and warming of air

Question 63

The internal nose has a rich blood supply from the internal and external carotid arteries. Name the branches of the internal AND external.

Answer 63

Internal Carotid: -anterior ethmoidal artery -posterior ethmoidal artery External Carotid: -Sphenopalatine artery -Greater palatine artery Superior labal artery -Lateral nasal artery

Question 64

Epsitaxis?

Answer 64

Nosebleed

Question 65

Where is the most common area for epsitaxis?

Answer 65

Little's area on the anterior septum

Question 66

Which plexus is found at the Little's area?

Answer 66

Kiesselbach plexus

Question 67

Where would posterior nasal bleeding usually come from?

Answer 67

Woodruff plexus

Question 68

Which plexus is easier to access and cauterise under local anaesthetic?

Answer 68

Kiesselbach plexus

Question 69

Which type of bleed is more likely to require nasal packing?

Answer 69

Posterior bleeding via Woodruff plexus

Question 70

What is usual first aid for a noseblled?

Answer 70

Pinching of the nose

Question 71

Which type of bleed does not respond to nose pinching?

Answer 71

Posterior bleed via Woodruff plexus

Question 72

What are some surgical management options for epistaxis?

Answer 72

Endoscopic ligation of sphenopalatine artery

Question 73

What are paranasal sinuses?

Answer 73

Air filled cavities lined by respiratory epithelium.

Question 74

Name the four groups of paranasal sinuses. HINT- named according to which bone they are located in

Answer 74

Frontal Maxillary Sphenoid Ethmoid

Question 75

Which sinuses are the most superior?

Answer 75

The 2 frontal sinuses

Question 76

What is the arterial supply for the frontal sinuses?

Answer 76

Anterior ethmoidal artery

Question 77

What is the sensation supply for the frontal sinuses?

Answer 77

Supraorbital nerve (branch of ophthalmic nerve).

Question 78

What is the drainage for the frontal sinuses?

Answer 78

Frontonasal duct into hiatus semilunaris

Question 79

Which sinuses are most posterior?

Answer 79

Sphenoid sinuses

Question 80

What is the sensation supply for the sphenoid sinuses?

Answer 80

Posterior ethmoidal nerve (branch of ophthalmic nerve)

Question 81

What is the arterial supply for the sphenoid sinuses?

Answer 81

Sphenopalatine artery Posterior ethmoidal artery

Question 82

What is the drainage for the sphenoid sinuses?

Answer 82

Spheno-ethmoidal recess

Question 83

Which type of surgery may be carried out for the resection of pituitary adenomas?

Answer 83

Trans-sphenoidal surgery

Question 84

What are the risks of a trans-sphenoidal surgery?

Answer 84

Close proximity to internal carotid artery so high bleeding risk. Risk of CSF leak, which will need repaired.

Question 85

Which of the sinuses are the largest?

Answer 85

Maxillary sinuses

Question 86

What is the drainage for the maxillary sinuses?

Answer 86

Hiatus semilunaris

Question 87

What is the arterial supply for the maxillary sinuses?

Answer 87

Branches of facial and maxillary arteries

Question 88

What is the innervation for the maxillary sinuses?

Answer 88

Superior alveolar nerves Greater palatine nerve Both branches of maxillary nerve

Question 89

There are two ethmoidal sinuses on either side of the face; an anterior and a posterior. What is the arterial supply for the ethmoidal sinuses?

Answer 89

Anterior ethmoidal artery Posterior ethmoidal artery

Question 90

There are two ethmoidal sinuses on either side of the face; an anterior and a posterior. What is the innervation for the ethmoidal sinuses?

Answer 90

Anterior and posterior ethmoidal branches of the nasociliary nerve

Question 91

What is orbital cellulitis?

Answer 91

Sight threatening emergency! Acute spread of infection from the sphenoid or frontal sinuses.

Question 92

What are some of the clinical signs of orbital cellulitis?

Answer 92

Proptosis (eye swelling) Chemosis (eye irritation) Ophthalmoplegia (weakness/paralysis in eye movements) Loos of colour vison and decreased visual acuity

Question 93

In those with orbital cellulitis, which colour will they lose vision of first?

Answer 93

Red

Question 94

What is the treatment of orbital cellulitis?

Answer 94

IV antibiotics Nasal decongestants

Question 95

Which imaging will be done in those with orbital cellulitis?

Answer 95

CT scan

Question 96

Sometimes surgery can be done in treatment of orbital cellulitis...what can be done?

Answer 96

Drainage

Question 97

What is sinusitis?

Answer 97

Inflammation of lining of sinuses

Question 98

What is the cause of acute sinusitis (<3months)?

Answer 98

Usually viral

Question 99

Chronic sinusitis is diagnosed when it's been present for >3months. It can be with or without polyposis. Describe the symptoms of chronic sinusitis.

Answer 99

Nasal obstruction Chronic nasal discharge Affect on smell

Question 100

What is the post-nasal space/ nasopharynx?

Answer 100

Area posterior to nasal cholanae extending down to the soft palate

Question 101

What are the contents of the post-nasal space/nasopharynx?

Answer 101

Adenoids Tubal tonsils Eustachian tube opening

Question 102

What may enlarged adenoids or eustachian tube obstruction result in?

Answer 102

Glue ear (otitis media with effusion).