A complete description of nose and paranasal sinuses

1. NOSE AND PARANASAL SINUSES
PRESENTED BY-
SRISHTI (91)
SRISHTI SWARAJ (92)
SRISHTI VERMA (93)
SRISTI PATHAK (94)
SUNIDHI ANAND (95)
Under the guidance of-
Dr. A.K. Srivastava
Head of department
Anatomy

2. CONTENTS
-NOSE
-Anatomical landmarks
-External nose
-Nasal cavity
-PARANASAL SINUSES
-Frontal sinus
-Maxillary sinus
-Sphenoidal sinus
-Ethmoidal sinus
-PTERYGOPALATINE FOSSA
-boundaries, communications and contents
-PTERYGOPALATINE GANGLION
-CLINICAL ANATOMY

3. ANATOMICAL LANDMARKS OF NOSE
• Nasion: midline point at which nasal bones join frontal bones
• Rhinion: inferior point of midline suture between nasal bones where they meet the
upper lateral cartilages
• Dorsum of nose: ridge formed by the union of lateral surfaces of nose in the midline
• Bridge of nose: anterior surface of nose formed by nasal bones
• Columella: midline nasal soft tissue anterior to septum separating the two nares
• Alae nasi: wings of nose at the inferior ends of the lateral nasal surfaces of nose

4. EXTERNAL NOSE
- Pyramidal projection of face
- Consists of : a) Tip b) Root c)
Dorsum
- Has skeletal framework that is partly
bony and partly cartilaginous
- The bones are – nasal bones, which form
the bridge of the nose and the frontal
process of maxillae
- The cartilages are superior and inferior
nasal cartilages, septal cartilage and
major and minor Alar cartilages

6. NERVE SUPPLY
-Infra-orbital branch of maxillary nerve
- Infratrochlear and external nasal branches of the ophthalmic
ARTERIAL SUPPLY
- lateral nasal branches of facial
- dorsal nasal branches of ophthalmic
- infra-orbital branch of the maxillary
LYMPHATIC DRAINAGE
- submandibular nodes drain the greater part of the skin
- superficial parotid nodes drain the skin of the root of nose

7. NASAL CAVITY
• The nasal cavity extends from the nostrils to posterior nares through which it opens into
naso-pharynx.
• It is divided into two halves by a septum.
• Each half has- a) roof
b) floor
c) medial wall or nasal septum
d) lateral wall

8. Nasal cavity

9. ROOF
The roof is about 7cm long and 2mm wide. It
slopes downwards both in front and behind.
-The middle horizontal part is formed by the
cribiform plate of ethmoid.
-The anterior slope is formed by the nasal part
of frontal bone, nasal bone and nasal cartilages
-The posterior slope is formed by the inferior
surface of the body of sphenoid bone.
FLOOR
-The floor is about 5cm long and 1.5cm wide.
- It is formed by palatine process of maxilla
and horizontal plate of palatine bone.
- It is concave from side to side and slightly
higher anteriorly than posteriorly.

10. MEDIAL WALL (NASAL
SEPTUM)
- The nasal septum is median osseocartilaginous
partition between the two halves of nasal cavity
- On each side, it is covered by mucous membrane and
forms the medial wall of both nasal cavities
- The bony part is formed by-
i) vomer
ii) perpendicular plate of ethmoid
- The cartilaginous part is formed by-
i) septal cartilage
ii) septal process of inferior nasal cartilage

11. ARTERIAL SUPPLY
-Anterosuperior part by anterior ethmoidal artey
-Posterosuperior part by sphenopalatine artery
-Anteroinferior part by superior labial branch of facial
artery
-Posteroinferior part by greater palatine branch of 3rd
part of maxillary
NERVE SUPPLY
-general sensory nerves
-internal nasal branch of anterior ethmoidal nerve
-anterior superior alveolar nerve
-nasopalatine branch of pterygopalatine ganglion

12. LATERAL WALL OF NOSE
-It is irregular owing to the presence of three shelf like
bony projections called conchae.
-The conchae increase the surface area of the nose for
effective air conditioning of the inspired air.
-The skeleton of lateral wall is partly bony, partly
cartilaginious
-The bony part is formed by nasal bones, frontal process of
maxilla, lacrimal bone, inferior nasal concha, perpendicular
plate of palatine bone.

13. ARTERIAL SUPPLY
1. The anterior ethmoidal branch of ophthalmic
supplies the anterosuperior part.
2. The sphenopalatine branch of maxillary supplies
the major part of the mucosa covering the
posterosuperior part.
3. The greater palatine branch of maxillary supplies
the posteroinferior part.
4. The alar branch of the facial supplies vestibule.
NERVE SUPPLY
Lateral wall of nose has the following sensory supply
in its four quadrants-
1. The anterior ethmoidal branch from the ophthalmic
division of trigeminal nerve.
2. The posterior-superior lateral nasal branches of the
pterygopalatine ganglion.
3. The posterior-inferior lateral nasal branches of the
greater palatine nerve.
4. Internal nasal branches of the infraorbital nerve.

14. CLINICAL ANATOMY
Little’s area on the septum is a
common site of bleeding from the
nose or epistaxis
Common cold or rhinitis is the
commonest infection of nose
Fracture of cribiform plate of ethmoid
with tearing off of meninges may tear
the olfactory nerve rootlets . In such
cases, CSF may drip from nasal
cavity. It is called CSF rhinnorhea

15. Adenoids or enlarged nasopharyngeal
tonsil in the nasopharynx can be
examined by posterior rhinoscopy.
Adenoids cause mouth breathing,
nasal obstruction and even blockage
of pharyngotympanic tube
Hypertrophy of the mucosa over the
inferior nasal concha is a common
feature of allergic rhinitis which is
characterized by sneezing, nasal
blockage, excessive watery discharge
from nose

16. Bifid nose results from an
incomplete fusion of medial
nasal processes
• The skin of external nose
consists of many sebaceous
glands which may get blocked to
form sebaceous cysts

17. PARANASAL SINUS
air filled spaces present
within some bones
around the nasal
cavities.
open into the nasal
cavity through its
lateral wall
The function is to
make the skull lighter
and add resonance to
the voice
rudimentary
or absent at
birth.
The sinuses are
frontal, maxillary,
sphenoidal and
ethmoidal

18. FRONTAL SINUS
-lies in the frontal bone deep to the superciliary arch
-Opens into the middle meatus of nose at the anterior end of hiatus semilunaris
-Average height, width and anteroposterior depth are each about 2.5cm
-Right and left sinuses are usually unequal in size
-Better developed in males than in female
-Rudimentary or absent at birth
-Arterial supply : supraorbital artery
-venous drainage : into the supra orbital and superior ophthalmic veins in
supraorbital notch
-Lymphatic drainage : to submandibular nodes
-Nerve supply : supraorbital nerve

19. FRONTAL SINUS

20. MAXILLARY SINUS
-lies in the body of maxilla
-Largest of all the paranasal sinuses
-Pyramidal in shape with base directed medially towards the lateral wall of nose and apex
directed laterally in the zygomatic process of maxilla
- Average measurements- height: 3.5cm, width: 2.5cm, anteroposterior depth: 3.5cm
- Roof is formed by floor of orbit and is traversed by infraorbital nerve. The floor is
formed by alveolar process of maxilla
- first paranasal sinus to develop
- Arterial supply: facial, infraorbital and greater palatine arteries
- Nerve supply: infraorbital and anterior, middle and posterior superior alveolar nerves
- Venous drainage: into the facial vein and pterygoid plexus of vein
- Lymphatic drainage: into submandibular nodes

21. MAXILLARY SINUS

22. SPHENOIDAL SINUS
-The right and left sphenoidal sinuses lie within body of sphenoid bone
-The two sinuses are usually unequal in size
-Each sinus opens into the sphenoethmoidal recess of corresponding half of the
nasal cavity
-Each sinus is related superiorly to the optic chiasma and hypophysis cerebri and
laterally to internal carotid artery and cavernous sinus
-Arterial supply: posterior ethmoidal and internal carotid arteries
-Venous drainage: into pterygoid venous plexus and cavernous sinus
-lymphatic drainage: to the retropharyngeal node
-nerve supply: posterior ethmoidal nerve and orbital branches of pterygopalatine
ganglion

23. SPHENOIDAL SINUS

24. ETHMOIDAL SINUS
-Ethmoidal sinuses are numerous small intercommunicating spaces which lie
within the labyrinth of ethmoid bone
-These sinuses are divided into anterior, middle and posterior groups
-The anterior ethmoidal sinus is made up of 1-11 air cells which is supplied
by anterior ethmoidal nerve and vessels
-The middle ethmoidal sinus consists of 1-7 air cells which is supplied by
posterior ethmoidal nerve and vessels and orbital branches of pterygopalatine
ganglion
-The posterior ethmoidal sinus consists of 1-7 air cells supplied by posterior
ethmoidal nerve and vessel and orbital branches of pterygopalatine ganglion

25. ETHMOID SINUS

26. PTERYGOPALATINE FOSSA
Small pyramidal space situated deeply below
the apex of orbit
BOUNDARIES:
Anterior- superomedial part of posterior
surface of the maxilla
Posterior- root of pterygoid process and
adjoining part of anterior surface of the greater
wing of sphenoid
Medial- upper part of perpendicular plate of
palatine bone
Lateral- the fossa opens into the infratemporal
fossa through the pterygomaxillary fissure
Superior- undersurface of body of sphenoid
Inferior- pyramidal process of palatine bone

28. COMMUNICATIONS
Anteriorly: with the orbit through medial end of the inferior orbital fissure
Posteriorly: with a) middle cranial fossa through foramen rotundum
b) foramen lacerum through pterygoid canal
c) pharynx through palatinovaginal canal
Medially: with nose through sphenopalatine foramen
Laterally: with infratemporal fossa through pterygomaxillary fissure
Inferiorly: with oral cavity through greater and lesser palatine canals
CONTENTS
-Third part of maxillary artery and its branches
-maxillary nerve and its 2 branches i.e zygomatic and posterior superior alveolar
-pterygopalatine ganglion and its branches

29. PTERYGOPALATINE GANGLION
-It is the largest parasympathetic
peripheral ganglion
-It serves as a relay station for
secretomotor fibres to the lacrimal gland
and to the mucous gland of nose,
paranasal sinuses, palate and pharynx
-It lies in the pterygopalatine fossa just
below the maxillary nerve, in front of the
pterygoid canal and lateral to
sphenopalatine foramen

30. BRANCHES
i. Orbital branches- pass through inferior orbital fissure and supply periosteum of
the orbit and orbitalis muscle
ii. Palatine branches- Supplies hard palate and the lateral wall of the nose
iii. Nasal branch- Lateral posterior superior nasal nerves supply posterior part of
conchae. Middle posterior superior nasal nerve supply posterior part of the roof
of nose and nasal septum. Nasopalatine nerve supplies hard palate
iv. Pharyngeal branch- supplies the part of the nasopharynx behind auditory tube
v. Lacrimal branch- supply secretomotor fibres to lacrimal gland

31. CLINICAL ANATOMY
Frontal sinusitis and ethmoiditis can
cause oedema of the lids secondary to
infection of the sinus
The pterygopalatine ganglion, if
irritated or infected causes congestion
of the glands or palate and nose
including the lacrimal gland producing
running nose and lacrimation. This
condition is called ‘Hay fever’
Infection of sphenoidal sinus
spreading upwards may effect the optic
chiasma

33. • A growth in maxillary sinus causes other symptoms due to pressure of
enlarging tumor on adjacent structures.
- By pressing the superior alveolar nerve and infra orbital nerves
leads to severe attacks of toothache.
- It can bulge forwards causing swelling in the face.
- Due to upward growth in orbit , it can push the eye forwards –
proptosis.
-It can also cause swelling of hard palate by pushing downwards

34. THANK YOU

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