Nose anatomy

Question 1

Paranasal sinus

- List the types

Answer 1

• Frontal
• Ethmoidal
• Sphenoid
• Maxillary

Question 2

All paranasal sinuses are lined by…

Answer 2

Respiratory epithelium

- Mucous and ciliated epithelium

Question 3

Frontal sinus

• Locatation and structure
• Drainage

Answer 3

Inferior forehead, inside frontal bone
- Paired traingular sinuses

Drains into middle meatus of the lateral nose wall via the frontonasal duct.

Question 4

Blood supply and innervation of the frontal sinus

Answer 4

Blood supply
- Anterior ethmoidal arteries (from opthalmic, of ICA)

Innervation
- Supra-orbital branch of the opthalmic nerve (CNV1)

Question 5

Ethmoidal cells

• Struture
• Drainage

Answer 5

Composed of a pair of three cells
- Anterior, middle and posterior

Anterior
- Opens into ethmoidal infundibulum/ frontonasal duct

Middle
- Opens into ethmoidal bulla

Posterior
- Lateral wall, superior nasal meatus.

Question 6

Blood supply and innervation of the ethmoidal cells

Answer 6

Blood supply from the anterior and posterior ethmoidal arteries (opthlamic branches, from ICA)

Innervation

• Anterior and posterior ethmoidal branches of the nasociliary nerve (opthalmic nerve, CNV1)
• Orbital branches from the pteryhopalantine ganglion of the maxillary nerve (CNV2)

Question 7

Maxillary sinuses

• Structure
• Drainage/ opening

Answer 7

Largest, paired sinuses, located in the maxillae.

Pyramidal shape
- Base formed of maxillae, inferior concha and palantine bone, next to lateral nose

Opens in the centre of the semilunar haitus, which grooves the middle nasal meatus.

Question 8

Maxillary sinuses

• Blood supply
• Innervation

Answer 8

Blood supply from the infra-orbital and superior alveolar branches of the maxillary arteries.

Innervated by the infra-orbital and alveolar branches of the maxillary nerve (CNV2)

Question 9

Sphenoid sinus

• Structure/ location
• Opening

Answer 9

Two cavities located within the sphenoid bone

• Posterior and superior to the nasal cavity
• Inferior to the cranial cavity, pituitary gland and optic chiasm
• Medial to cavernous sinuses

Opens into the roof of the nasal cavity via an aperture in the spehno-ethmoidal recess

Question 10

Blood supply and innervation of the sphenoidal sinuses

Answer 10

Blood is supplied by the pharyngeal arteries from the maxillary arteries.

Innervation:

• Posterior ethmoidal branch of the ophthalmic nerve (CNV1)
• Orbital branches of the pterygopalantine ganglion of CNV2 (maxillary)