Amatomy of Nose

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Transcript Amatomy of Nose

Objectives:
 By the end of this lecture we are going to be able to:
 Describe the anatomical structure and features of the
nose
 Identify the bones forming the nasal cavity
 Recognize arterial supply, and venous drainage of the
nose
 Identify different Para nasal sinuses and their
functions
Nasal Cavity
- The cavity of the nose is subdivided into right and
left halves by the nasal septum.
- The two halves open anteriorly on the face through
the nostrils (anterior nares), and open posteriorly
into the nasopharynx through the posterior nasal
aperture.
Bony skeleton of the nose
I. Roof, formed by:
- Anterior part------ Nasal part of the frontal
bone + Nasal bone.
- Middle part ------ Cribriform plate of the
ethmoid bone.
- Posterior part------Body of the sphenoid
bone.
I. Floor, formed by:
- Anteriorly: Palatine process of the maxilla.
- Posteriorly : Horizontal plates of the
palatine bone.
III. Medial wall (nasal septum), formed
by:
- Postero-inferior-------Vomer.
- Superiorly ----- Perpendicular plate of the
ethmoid bone.
- Antero-inferior -----Septal cartilage.
(Roof, floor, and medial
wall of the nose)
Lateral wall of the nose
- The lateral wall of the nose is
subdivided into three areas which are:
A. Vestibule
B.Nasal conchae and meatuses:
1. Conchae
- They are bony plates covered with
mucous membrane.
- They are three (superior, middle, and
inferior nasal conchae).
2. Meatuses
- They are depressions below and lateral
to each concha (superior, middle, and
inferior meatuses).
-Superior meatus : It receives the
opening of posterior ethmoidal air sinus.
Lateral wall of the nose
b. Middle meatus : It has
* Bulla ethmoidalis:
- It is a rounded elevation where the
middle ethmoidal air sinus opens in it.
* Hiatus semilunaris:
- It is a crescenteric groove () lying
below the bulla ethmoidalis.
- It receives the following openings:
i. Anterior ethmoial air sinus.
ii. Frontal air sinus.
iii. Maxillary air sinus.
c. Inferior meatus (below the inferior
nasal concha):
- It receives the nasolacrimal duct.
d. Spheno-ethmoidal recess:
- It is a triangular fossa between the
superior concha and the roof of the
nose.
- It receives the opening of the
sphenoidal air sinus.
Arterial supply of the nose
1. Sphenopalatine artery
- It is a branch from the maxillary artery (main
arterial supply).
2. Septal branch of the superior labial
artery from facial artery.
3. Ascending branch of the greater
palatine artery from the maxillary
artery .
- There is anastomoses between the above
three arteries to form “Kieselbach's
plexus” on the antero-inferior part of the
nasal septum (Little’s area).
- This area is a common site for epistaxis
(bleeding from the nose).
4. Anterior and posterior ethmoidal
branches of the ophthalmic artery.
supply the roof and upper parts of the lateral
wall and septum.
Sphenopalatine Ganglion
Type: Parasympathetic ganglion.
Site: In the pterygopalatine fossa.
Roots (preganglionic fibers):
1. Sensory: From the maxillary
nerve.
2. Sympathetic supply: Deep
petrosal nerve which arises
from the sympathetic plexus
around the internal carotid
artery.
3. Parasympathetic: Greater
petrosal nerve (from facial N)
Sphenopalatine Ganglion (branches)
1. Postganglionic secretomotor fibers which supply
the lacrimal gland.
2. Lesser palatine nerves.
3. Greater palatine nerve .
- It gives the lateral posterior
inferior nasal nerves.
4. Lateral and medial
posterior superior nasal
nerves.
5. Nasopalatine nerve. ( long
sphenopalatine)
6. Pharyngeal branch to the
pharynx.
7. Branches to the orbital
periosteum.
NB: The postganglionic branches
of the sphenopalatine ganglion
supply the mucous glands of the
palate, nose, nasopharynx and
the lacrimal gland.
Nerve supply of the nose
I. Lateral wall
- Olfactory area (1 cm)  Olfactory nerves.
(this area includes the roof and upper parts of the septum and lateral nasal walls)
- Vestibular area Infraorbital nerve.
- Respiratory area of the lateral wall:
a. Antero-superior  anterior ethmoidal N.
b. Antero-inferior (inf. concha)  Internal nasal nerve(from anterior ethmoidal N)
c. Postero-superior Lateral posterior superior nasal brs.
d. Postero-inferior Lateral posterior inferior nasal brs (from greater palatine N).
II. Nasal septum
- Olfactory area Olfactory N.
- Anterior part  Internal nasal N. (from the anterior ethmoidal nerve).
- Postero-superior part  Medial posterior superior nasal branches. (from
sphenopalatine ganglion).
- Postero-inferior part  Nasopalatine nerve.
( long sphenopalatine nerve).
N.B: The nasopalatine nerve, greater and lesser palatine nerves, medial
and lateral posterior superior nasal nerves, and the posterior inferior
nasal nerve are branches from the sphenopalatine ganglion.
Para-nasal Air Sinuses
Definition:
- They are air-filled spaces in certain bones
which form the boundary of the nasal
cavity.
- They open into the lateral wall of the nose.
Functions:
1. Warming and humidifying the inspired air.
2. Diminishing the weight of the skull.
3. They add resonance to the voice.
Types:
1. Maxillary sinus -------- Inside
the body of the maxilla.
2. Frontal sinus ----------Between the two plates of the
frontal bone.
3. Sphenoid ---------------- Inside
the body of the sphenoid bone.
4. Ethmoid ----------------- Inside
the lateral part of the ethmoid
bone
- All the sinuses are present at birth
except the frontal sinus which
appears during the second year.
Thank You
Prof.: Dr. Wafaa Abdel-Rahman