ENT Students Nose Anatomy
5External nose
It consists of bony & cartilagenous parts:

10The nasal cavity
The nasal cavity consists of 6 walls:
1-Anterior and posterior nares (aperture, choana).
2-Medial wall ; the septum.
5-Lateral wall.
15The medial wall, the septum
The septum consists of:
1-Quadrangular cartilage.
2-Perpindicular plate of the ethmoid.
4-Maxillary crest.

20The lateral wall
It consists of 3 turbinates & meati: superior, middle and inferior.

25The paranasal sinuses (PNS)
These are air filled spaces that :
1-lighten the skull.
2-Help in resonance of sound.
3-Insulates the brain from the atmospheric pressure.
4-Help in humidification of the inspired air.
It includes: maxillary, frontal, ethmoids and sphenoid sinuses.
30The maxillary sinus
-Pyramidal in shape:

35The frontal sinus
-It is triangular in shape with base down:

40The ethmoid sinuses
-They are 5-15 cells arranged as anterior & posterior group.

45The sphenoid sinus
-It lies within the body of sphenoid bone:

47PNS ostia
The openings of the paranasal sinuses in the middle & superior meati & sphenoethmoidal recess.

50Normal CT scan
Axial and coronal

55The normal endoscopic view

60Blood supply of the nose
The nose is supplied from:
1-Anterior and posterior ethmoid arteries from the ICA.
2-Greater palatine artery of maxillary (ECA).
3-Superior labial branch of facial artery (ECA).
4-Sphenopalatine artery of the maxillary (ECA).

The confleunce of the arteries is called the Little`s area (marked by red color).
65The mucociliary clearance

70Examination of the nose
Tools used for examination: the nasal speculum and the sinuscope.