2. Nasal septum divides the nasal cavity into
two halves
It is often deviated from the median plane –
makes the two halves of nasal cavity
asymmetrical
Most of the septum is lined by mucous
except the mobile part
The mobile part of septum is covered by skin
Nasal septum is partly bony and partly
cartilaginous
4. BONY PART
i. Perpendicular plate of ethmoid
ii. Vomer
iii.Nasal spine of frontal bones
iv.Sphenoidal crest
v. Nasal crest formed by nasal bones
vi.Nasal crest formed by palatine
process
of maxillae and palatine bones
PRINCIPLE BONES
ACCESSORY
BONES
5. Perpendicular Plate Of Ethmoid
It forms the antero superior part of
septum
Articulations
Upper margin – continuous with
cribriform plate
Anterosuperior – nasal spine of
frontal bone
Anteroinferior – septal cartilage
Posterosuperior- sphenoid
Psteroinferior - Vomer
6. Vomer
It forms the postero inferior part of the septum
Articulations
Upper margin – Sphenoid rostrum
Lower margin – Nasal crest by maxillae and palatine
Posterior margin – Free; forms medial boundary of
chonchae
Anterior margin – Perpendicular plate of ethmoid
7. CARTILAGENOUS PART
i. Septal Cartilage
Forms the major anterior part of septum
Fits in the angle between ethmoid and Vomer
ii. Septal Processes
From major alar cartilage
United together in the midline by fibrous tissue and form
coloumnella
9. ARTERIAL SUPPLY
Anterosuperior part –
Anterior ethmoidal
branch of opthalmic
artery
Posteroinferior part –
Sphenopalatine and
Greater palatine
branches of Maxillary
artery
Mobile part of septum –
Superior labial branch of
facial artery
10. KIESSELBACH’S PLEXUS
Little’s Area
Its an area in antero inferior part of the nasal septum just above the
vestibule. It is highly vascular where the septal branches of anterior
ethmoidal , sphenopalatine, greater palatine and superior labial
artery anastamose to form vascular kiesselbach’s plexus. This is the
most common area of epistaxis.
11. VENOUS DRAINAGE
Antero superior part – Into superior opthalmic vein
Postero inferior part – into pterygoid venous plexus
Mobile part of septum – Into internal jugular vein
hrough facial vein
Upper part of septum – Veins accompany the
olfactory nerves and drain into the inferior cerebral
veins
12. Lymphatic drainage
From anterior part – into the submandibular
lymph nodes
From intermediate and posterior parts – into the
reteropharyngeal lymph nodes
From the upper part – Lymphatics along the
olfactory nerves drain into sub arachnoid spaces
14. NERVE SUPPLY
Olfactory Nerves – Upper part just below cribriform
plate in the olfactory zone
Internal nasal branch of anterior ethmoidal–
Anterosuperior quadrant
Anterosuperior alveolar nerve – anteroinferior
quadrant
Posterior, superior, medial branches of
Pterygopalatine ganglion – Posterosuperior quadrant
Nasopalatine – posteroinferior quadrant
Nasal branch of greater palatine – posterior part
15. CLINICAL CORRELATION
Deviated Nasal Septum
Important cause of nasal obstruction
Males are affected more than females
May occur due to trauma ,developmental error
etc.
If DNS is severe, it causes mechanical obstruction
Symptoms include difficulty in breathing,
headache, excessive snoring
Corrected by submucous resection or septoplasty