paranasal sinus

1. ANATOMY OF
PARANASAL SINUSES
PRESENTED BY - GURJAR GANESH KUMAR

2. CONTENT
• To know anatomical location
• Their connections & significance
• Development
• Neurovascular supply
• Venious drainage
• Clinical importance
• functions

3. INTRODUCTION
• Air containing cavities.
• Each sinus are named
after the bone it resides in.
• 4 pairs- frontal, sphenoid,
ethmoid, maxillary .

4. 1.MAXILLARY SINUS
• Largest paranasal sinuses
• Pyramidal in shape
• Base pointing to lateral wall of
nose
• Apex laterally in the zygomatic
process
• Capacity 15 ml

5. RELATIONS
• Anterior- facial surface of maxilla
• Posterior- infratemporal and
pterygopalatine fossa
• Medial – middle and inferior meatus
• Floor – alveolar and palatine
processes of maxilla
• Roof – floor of orbit

6. NEUROVASCULAR SUPPLY
• Blood supply - Facial , infra orbital, greater palatine arteries.
• Lymphatic drainage – Submandibular nodes.
• Nerve supply – Infra orbital , anterior, middle and post superior
alveolar nerves.

7. 2.FRONTAL SINUS
• Resides in frontal bone
• 2nd largest
• Asymmetrical
• Usually paired- sometimes one,
three , or none!

8. RELATIONS
• Anterior- skin over the forehead
• Inferior- orbit &its contents
• Posterior- meningeal and
frontal lobe of brain

9. NEUROVASCULAR SUPPLY
• Blood supply – Supra orbital artery, Anterior ethmoidal arteries.
• Venous return – Anastomotic veins in supra orbital notch, connecting
supra orbital and supra ophthalmic veins.
• Lymphatic drainage – Submandibular nodes.
• Nerve supply- Supra orbital nerve traversing the floor of the sinus.

10. 3.ETHMOIDAL SINUS
• Resides in ethmoid bone
• 3 groups- anterior, posterior,
middle ethmoidal sinus
• Number varies from 3-18
• Present from birth

11. RELATIONS
• Roof – anterior cranial fossa
• Lateral - orbit( separated by
lamina papyracea)
• Optic nerve lies close to
posterior ethmoidal cells.

12. 1. Anterior ethmoidal sinus- it is made up of 1to11 air cells , opens into the anterior part
of
the hiatus semilunaris of the nose.
- Nerve supply : anterior ethmoidal nerve.
- Lymphatics drainage: submandibular nodes.
2. Middle ethmoidal sinus - it is consisting of 1 to 7 air cells , opens into the middle
meatus of
the nose.
- Nerve supply : anterior ethmoidal nerve and the
orbital branches of the pterygopalatine
ganglion.
- Lymphatics drainage : submandibular nodes.
3. Posterior ethmoidal sinus – it is consisting of 1 to 7 air cells , opens into the superior
meatus of nose.
- Nerve supply : posterior ethmoidal nerve and the
orbital branches of the pterygopalatine
ganglion.

13. 4.SPHENOID SINUS
• Resides in body of sphenoid
• Maybe single or paired
• Asymmetrical
• Not present at birth
• Lies below to sella turcica
• Sphenoid effusion shows skull base
fracture
• Related to optic tract, chiasma ,internal
carotid artery.

14. NEUROVASCULAR SUPPLY
• Blood supply – Posterior ethmoidal artery.
• Lymphatic drainage – Retropharyngeal nodes.
• Nerve supply – Posterior ethmoidal nerve.

15. DEVELOPMENT

16. FUNCTION OF PARANASAL SINUS
• Humidifying and warming inspired air
• Regulation of intranasal pressure
• Increasing surface area for olfaction
• Lightening the skull
• Resonance
• Absorbing shock
• Contribute to facial growth

17. CLINICAL IMPORTANCE
• The paranasal sinuses are joined to the nasal cavity via small orifices called ostia.
• These become blocked easily by allergic inflammation or by swelling in the nasal
lining that occurs with a cold.
• If this happens , normal drainage of mucus within the sinuses is disrupted and
sinusitis may occur.
• Because the maxillary posterior teeth are close to the maxillary sinus , this can also
cause clinical problems if any disease processes are present , such as an infection in
any of these teeth.
• These clinical problems can include secondary sinusitis , the inflammation of the
sinuses from
Another source such as an infection of the adjacent teeth.

18. These conditions may be
treated with drugs such as
decongestants ,
Which cause vasoconstriction
in the sinuses , reducing
inflammation
By traditional techniques of
nasal irrigation or by
corticosteroid.

19. CARCINOMA OF PARANASAL SINUS
• Malignancies of the paranasal
sinuses comprise approximately
0.2% of all malignancies . About
80% of these malignancies arise in
the maxillary sinus . Men are much
more often affected than women .
They most often occur in the age
group between 40 and 70 years .
carcinomas are more frequent than
sarcomas . Metastases are rare.
Tumours of the sphenoid and frontal
sinuses are extremely rare.

20. REFERANCE
• Bd chaurasia’s anatomy
• Gray’s anatomy
• Sources of google

21. Thank you!