Nasal Anatomy

Question 1

What is the function of the nose/nasal cavity?

Answer 1

• Allows air transmition
• Humidification (95%) and warming of air
• Associated with vocal sounds
• Olfaction
• Filtration and protection

Question 2

1. Name the features of the external part of the nose (draw a diagram if needed)
2. Describe the internal anatomy of the nasal cavity (draw and label a diagram). What mucosa does the internal cavity consist of?
3. What are the risks of nasal intubation?

Answer 2

1.

• Nostril = nares
• Columella = middle between the nostrils
• Philtrum is below this
• Vermillion os the notch of the lip below that

2.

• Superior (smallest), Middle and Inferior (Largest) turbinates. Originate from the lateral walls
• Eustasian tube
• Septum seperates the two cavities
• Consists of respiratory and olfactory lining

3.

• Mucosal trauma (friable tissue)
• Bleeding (esp from littles area)
• Blockadge of sinuses (if left in a long time) –> collapse of the sinuses and sinking of the eye in severe cases
• Fracture of the turbinate
• Amputation of the turbinate bone

Question 3

What is the arterial supply of the nose?

Answer 3

Sphenopalatine artery- supplies most of the mucosa

Ant and Post ethmoidal a. supply nasal mucosa posteriorly (continuation of the facial a.)

Greater palpatine a. supplies septum

Question 4

1. What is the sensory invervation of the nose?
2. Where is the sense of smell derived and where are these receptors found?
3. Where do the secreto-motor fibres come from?

Answer 4

1. opthalmic and maxillary div CNV (trigeminal)
2. Olfactory nerve supplies epithelium in the superior aspect of the cavity
3. Secreto-motor fibres and distributed via PTERYGOPALPATINE ganglion

Question 5

1. Name the paranasal sinuses
2. Functions
3. How do they drain, how can they be blocked and what is the consequence of this?

Answer 5

1. Frontal, Ethmoidal, Sphenoidal, Maxillary
2. Functions:

• decrease skull weight
• aid vocal resonance
• provide crumple zones

3. Drain via ostia into nasal cavity

Can be blocked leading to sinusitis, can be caused by NT tubes.

Rarely they shrink lowering the eye above (maxillary)