anatomy of nose. bones and cartilage involved, walls of nasal cavity, the conchea, blood supply nerve supply and lymphatic drainage

1. NOSE & PARA NASAL
SINUS
Dr sana yaseen
Lecturer
Anatomy department

2. INTRODUCTION
The nose is an olfactory and respiratory organ. It consists of nasal
skeleton, which houses the nasal cavity. The nasal cavity has four
functions:
Warms and humidifies the inspired air.
Removes and traps pathogens and particulate matter from the
inspired air.
Responsible for sense of smell.
Drains and clears the paranasal sinuses and lacrimal ducts.

3. DIVISION:
a) EXTERNAL NOSE
b) NASAL CAVITY

4. EXTERNAL NOSE
The external part of the nose
consists of
a root (superiorly), apex (inferiorly),
dorsum, nares (nostrils) and the
separating nasal septum.
Bony component: nasal, maxillae
and frontal bones
Cartilaginous component: alar
cartilages (major, minor), lateral
processes, septal cartilage

5. NASAL CAVITY
Extends from external nose to posterior nasal septum
It has roof, floor, medial and lateral wall
Cavity separates from
Each other (medial) – midline septum
Oral cavity (below) – nasal septum
Cranial cavity (above) – frontal , ethmoidal, sphenoid
Orbit (lateral) - orbit

6. ROOF OF NASAL CAVITY
Slopes down
Front – frontal bone , nasal bone , nasal cartilage
Middle horitontal part- cribriform plate
FLOOR OF NASAL CAVITY
Palatine process of maxilla
Horizontal plate of palatine bone

7. MEDIAL WALL
Is osteocartilagenous
Bone- vomer, perpendicular plate of ethmoid bone
Cartlage- septal cartilage , septal process of inferior nasal cartilage
Lower end part / cuticular part – fibro fatty tissue

8. ARTERIAL SUPPLY:
Anterior ethmoidal artery
Posterior ethmoidal artery
Superior laial artery
Sphenopalatine artery
VENOUS DRAINAGE:
Anteriorly: facial vein
Posteriorly : pterygoid venous plexus

9. LITLE’S AREA
Site of anastomosing of vessels and so it common site of bleeding
from nose/ epistaxis
Capillary network called KIESSEL BACH’S PLEXUS located in antero
inferior part / vestebule of septum .
Vessels involved superior labial and branch of sphenopalatine

10. NERVE SUPPLY
General sensory:
antero superior: anterior ethmoidal nerve
Posteroinferior: nasopalatine branch of
pterygopalatine ganglion
Posterosuperior: medial, posterio, superior
branch of pterygopalatine ganglion
special sensory: olfactory nerve
LYMPHATICS:
Anterior half: submandibular
Posterior half: retropharyngeal and deep
cervical

11. LATERAL WALL & NASAL CONCHAE
Is osteocartilagenous
Posses 3 curves of bone called CONCHEA.
Namely – inferior, middle and superior.
They project into the nasal cavity, creating four pathways for the air to flow.
These pathways are called meatuses:
Inferior meatus – between the inferior concha and floor of the nasal cavity.
Middle meatus – between the inferior and middle concha.
Superior meatus – between the middle and superior concha.
Spheno-ethmoidal recess – superiorly and posteriorly to the superior concha.

12. The function of the
conchae is to increase
the surface area of the
nasal cavity – this
increases the amount
of inspired air that can
come into contact with
the cavity walls.
They also disrupt the
fast, laminar flow of
the air, making it slow
and turbulent.
 The air spends longer
in the nasal cavity, so
that it can
be humidified.

13. ARTERIAL SUPPLY
Antero superior: ant ethmoidal , post ethmoidal, facial
Anteroinferior: facial, great palatine
Postero superior: sphenopalatine
Posteroinferior: great palatine
VENOUS DRAINAGE
Posterior : pharyngeal plexus
Middle: pterygoid plexus
All drain into facial vein

14. INNERVATION
General sense : trigeminal nerve
Special : olfactory

15. DIVISIONS
The nasal cavity is the most superior part of
the respiratory tract. It extends from the
vestibule of the nose to the nasopharynx,
and has three divisions:
1. Vestibule – the area surrounding the
anterior external opening to the nasal
cavity.
2. Respiratory region – lined by a ciliated
psudeostratified epithelium, interspersed
with mucus-secreting goblet cells.
3. Olfactory region – located at the apex of
the nasal cavity. It is lined by olfactory
cells with olfactory receptors.

16. OPENINGS INTO THE NASAL CAVITY
1. The paranasal sinuses drain into the nasal cavity. The frontal,
maxillary and anterior ethmoidal sinuses open into the middle
meatus.
The only structure not to empty out onto the lateral walls of the nasal
cavity is the sphenoid sinus. It drains onto the posterior roof.
2. Nasolacrimal duct – acts to drain tears from the eye. It opens into
the inferior meatus.
3. Auditory (Eustachian) tube – opens into the nasopharynx at the level
of the inferior meatus. It allows the middle ear to equalise with the
atmospheric air pressure.

18. PARANASAL SINUS

19. FRONTAL SINUS
Front bone deep to superciliary
arch
Opens into : middle meatus via
frontonasal duct
SPHENOIDAL SINUS :
In body of sphenoid
Opens into: nasal cavity
MAXILLARY SINUS
In maxilla
Opens into: midle meatus via
hiatus seminularis
ETHMOIDAL SINUS
Lateral wall of ethmoidal bone
Opens:
-anterior: ethmoidal
infundibulum
- middle : near bulla ethmoidalis
- posterior: superior meatus

20. THANK YOU...