Anatomy of nose

1. Dr Ganga N Devikeri
1st year PG scholar
Dept of shalakya tantra
Sjgamc koppal

2. The nose is divided into two parts
1. External nose
2. Internal nose

3. The external nose is pyramidal in
shape present anteriorly on the face.
it upper narrow part forms root of the
nose while broad lower part with
openings is called base of the nose
base is directed downward.
The pyramidal nose consist of
osteocartilaginous framework covered
by muscles and skin

4. Nasal pyramid is an
osteocartilaginous
framework upper one
third part is bony while
the lower two third part
is cartilaginous

5. Upper one third of the
external framework of nose is
contributed by hard bone.
The bony part is formed by
two nasal bones which meet
in midline and rest on upper
part of the nasal process of
the frontal bones and are also
themselves held between the
frontal process of maxillae

6. 1.Upper lateral cartilage
2.Lower alar cartilage(alar cartilage)
3.Lesser alar cartilage(sesampid cartilage)
4.Septal cartilage

7. These cartilages extend from the undersurface of the nasal bones
above,to the alar cartilage below.
Anterioly ,these cartilages fues with each other and with the upper
border of the septal cartilage in the midline .
The lower edge of upper later cartilage is free and can be seen
intranasally as limen vestibulli or nasal valve on each side seperately

8. Each of the alar cartilages is U-shaped which has two crus i-e
lateral crus and medial crus.
The lateral crus form the ala of nose and medial crus becomes the
part of columella.
The lateral crus of alar cartilage overlap the lower edge of upper
lateral cartilage on each side (covers the free edge of upper lateral
cartilages which form limen vestibuli or nasal valve on each side).

9. These are two or more in numbers which lie above and
lateral to the alar cartilages.
Perichondrium and periosteum connects these cartilages
with one another and with the adjoining bones.
The free edge or margin of nostril is formed by the
fibrofatty tissue in most of the part (posterior of the margin)
and not by the alar cartilages (alar cartilages form only
some portion of anterior of the margin of nostril).

10. Septal cartilage is the midline structure with its anterosuperior border
running from undersurface of nasal bone to the nasal tip.
It provides support to the dorsum of cartilaginous part of nose

11. Nasal musculature covers the osteocartilaginous
framework of the nose and is responsible for the
movement of the nasal tip, ala and the overlying
skin. These are the procerus, nasalis (transverse
and alar parts), levator labii superioris Alaeque
nasi, anterior and posterior dilator nares and
depressor septi.

12. The skin over the nasal bones
and the upper lateral
cartilages is thin and freely
mobile, while that covering
the alar cartilages is thick
and closely adherent and
rich of sebaceous gland.

13. Nasal septum divides the internal nose into
right and left nasal cavities.
Each nasal cavity has communication with
the exterior through naris or nostril and with
the Nasopharynx through posterior nasal
aperture or choana.

14. Nasal cavity is partitioned into two areas i-e skin lined portion, the
vestibule and a mucosa lined portion, the nasal cavity proper.
a)Vestibule of nose
b)Nasal cavity proper

15. Vestibule is anterior and inferior part of the nasal cavity.
It is lined by skin (keratinized stratified squamous epithelium) and
contains sebaceous glands, hair follicles and hair called vibrissae

16. Nasal valve is bounded laterally by the lower border of upper lateral
cartilage (limen vestibuli) and fibrofatty tissue and anterior end of
inferior turbinate.
Medially the structure present is nasal septum, and caudally the
floor of pyriform aperture.

17. The nasal cavity proper is the rest portion of internal nose other
than the vestibule. Each nasal cavity has a lateral wall, a medial
wall, a roof and a floor.
i. Lateral nasal wall
ii. Medial nasal wall
iii. Roof
iv. Floor

18. On the lateral wall of the nose,
three and occasionally four
turbinates or conchae are well
demarcated.
Conchae or turbinates are scroll
like bony projections covered by
the mucous membrane.
The spaces between the
turbinates are called meatuses.

19. Inferior turbinate is the separate bone while the other turbinates
are the bony projections of various bones
Below it, into the inferior meatus, opens the nasolacrimal duct.
At the terminal end of the nasolacrimal duct, a mucosal valve
called Hasner’s valve is present that guard it.

20. Middle turbinate is ethmoturbinal i-e middle turbinate is the part of
ethmoid bone.
It’s attachment to the lateral wall is by a bony lamella called
ground or basal lamella which is in S-shaped manner, not in
straight line.
In the anterior third, it lies in sagittal plane and is attached to lateral
edge of cribriform plate.

21. In the middle third, it lies in frontal plane and is attached to lamina
papyracea while in its posterior third, it runs horizontally and forms
roof of the middle meatus and is attached to lamina papyracea and
medial wall of maxillary sinus.
The anterior group of paranasal sinuses is the ostia of various
sinuses draining anterior to basal lamina while the posterior group
of paranasal sinuses is those opening into posterior and superior to
basal lamina.

22. Middle meatus is related with several important structures which
are important in endoscopic surgery of the sinuses.
Uncinate process is a hook like structure running in from
anterosuperior to posteroinferior direction.
It posterior border is sharp and runs parallel to anterior border of
bulla ethmoidalis.

23. The gap between the two is called is hiatus semilunaris
(inferior), a two dimensional space 1-2 mm in width.
The anteroinferior border of uncinate process is attached to the
lateral wall and the posteroinferior end of uncinate process is
attached to inferior turbinate dividing the membranous part of
lower middle meatus into anterior and posterior fontanelle.

24. Bulla ethmoidalis is an ethmoidal cell situated behind the uncinate
process.
The anterior surface of the bulla forms the posterior boundary of
hiatus semilunaris.
Bulla ethmoidalis may be a pnematized cell or a solid bony
prominence depending upon the degree of pnematization.
The suprabullar and retrobullar recesses together form the lateral
sinus (sinus lateralis of Grunwald).

25.  The lateral sinus is thus bounded superiorly by the skull base, laterally by
lamina papyracea, medially by middle turbinate and inferiorly by the bulla
ethmoidalis.
 Posteriorly, the sinus lateralis may extend up to basal lamella of meddle
turbinate.
 The cleft like communication between the bulla and skull base and opening
into middle meatus in also called hiatus semilunaris superior in contrast to
hiatus semilunaris inferior referred to before.

26. Atrium of the middle meatus is a shallow depression lying in front of
middle turbinate and above the nasal vestibule.

27. Superior turbinate is also an ethmoturbinal i-e a part of ethmoidal
bone. It is situated posterior and superior to middle turbinate. It
may also get pnematized by one or more cells. It is an important
landmark to identify ostium of sphenoid sinus which lies medial to
it.

28. Likewise other meatus, superior meatus is the space present below
the superior turbinate respectively. Posterior ethmoidal cells have
opening into it. Posterior ethmoidal cells vary from 1-5 in numbers.
Onodi cell is a posterior ethmoidal cell which may grow posteriorly
by the side of sphenoid sinus or superior to it for as much distance as
1.5 cm from the anterior surface of sphenoid.

29. Sphenoethmoidal recess is situated above the superior turbinate.
Sphenoid sinus opens into it.

30. Sometimes, a fourth turbinate called supreme turbinate is also
present above the superior turbinate and has a narrow meatus
beneath it.
The ostium of sphenoid sinus is situated in the sphenoehtmoidal
recess medial to the superior or supreme turbinate. It can be located
endosceopically about 1 cm above the upper margin of posterior
choana close to the posterior border of the septum.

31. Nasal septum forms the medial wall of the nose. The detail anatomy
is described separately as it is a structure of utmost importance and
has surgical value in clinical cases.

32. The roof the nose has three parts i-e anterior part, middle part and
posterior part of roof. The anterior sloping part of the roof is formed
by the nasal bones, posterior sloping part is formed by the body of
sphenoid bone and the middle horizontal part is formed by
cribriform plate of ethmoid through which the olfactory nerves enter
the nasal cavity.

33. The floor of the nose is formed by palatine process of the maxilla in
its anterior three-fourths and horizontal part of the palatine bone in
its posterior one-fourth.

34. Lining membrane of the internal nose is different is it various part
i-e vestibule and other areas of internal nose have different lining
membrane related with their functions.

35. Vestibule is lined by normal skin containing hair, hair follicles and
sebaceous glands.

36. Upper one third of the lateral wall (up to superior concha),
corresponding part of nasal septum and the roof of nasal cavity
form the olfactory region. Here mucous membrane in paler in color.

37.  lower two thirds of the nasal cavity form the respiratory region. Here
mucous membrane shows variable thickness being thickest over nasal
conchae especially at their ends, quite thick over the nasal septum but
very thin in the meatuses and floor of the nose.
 This part of the membrane is highly vascular and also contains erectile
tissue.
 The lining epithelium is pseudostratified ciliated columnar epithelium
which contains plenty of goblet cells.
 In the submucous layer of mucous membrane are situated serous,
mucous, both serous and mucous secreting glands, the ducts of which
open on the surface of mucosa.

38. Three types of nerves supply the nose;
1.Olfactory nerves
2.The nerves of common sensation
3.Autonomic nerves

39. end in the olfactory bulb These nerves carry the sense of smell and
supply the olfactory region of the nose.
These are the central filaments of the olfactory cells and are
arranged into 12-20 nerves which pass through the cribriform plate
and .

40. The following nerves carry common
sensations from the nose
1. Anterior ethmoidal nerve
2. The braches of sphenopalatine ganglion
3. The braches of infraorbital nerve
These supply vestibules of the nose both on
its medial and lateral side.
The most of the posterior two-third of nasal
cavity (both septum and nasal wall) are
supplied by braches of sphenopalatine
ganglion.

41. Parasympathetic Nerve Fibers
The parasympathetic nerve fibers supply the nasal glands and
control the nasal secretions.
These come from greater superficial petrosal nerve, travel in the
nerve of pterygoid canal (vidian nerve) and reach the
sphenopalatine ganglion where these relay before reaching the
nasal cavity.
These nerves also supply the blood vessels of the nose and cause
vasodilation.

42. Sympathetic nerve fibers
Sympathetic nerve fibers come from upper two thoracic segments
of spinal cord, pass through superior cervical ganglion, travel in
deep petrosal nerve and join the parasympathetic fibers of greater
petrosal nerve to form the nerve of pterygoid canal (vidian nerve).
These nerves reach the nasal cavity without relay in the
sphenopalatine ganglion.
The stimulation of these nerves causes vasoconstriction.

43. Branches from both the internal
and external carotid systems supply
the nose.

44. Lymphatics from the external nose and anterior part of nasal cavity
drain into submandibular lymph nodes while those from the rest of
nasal cavity drain into upper jugular nodes either directly or through
the retropharyngeal nodes.
Lymphatics of the upper part of the nasal cavity communicate with
subarachnoid space along the olfactory nerves.