1. ANATOMY OF THE ORBIT
Dr Sheetal Savur

2. The orbit
Protects, supports and maximizes the functions of the eyeball
Shaped as a quadrilateral pyramid with its base in plane with the orbital rim

3. Alignment of the orbits
medial walls are parallel
lateral walls are perpendicular
axes of the orbits bisect at a 45°angle
The axes of the eyeballs make an angle of 22.5 with the orbital axes

4. Dimensions of the orbit
Height of orbital margin - 40 mm
Width of orbital margin - 35 mm
Depth of orbit mm
Volume of orbit - 30 cm3

5. Bones of the orbit Frontal bone Zygomatic bone Maxillary bone
Sphenoid bone
Ethmoid bone
Lacrimal bone
Palatine bone

6. The seven bones

7. The frontal bone

8. The zygomatic bone

9. The maxillary bone

10. The sphenoid bone

11. The ethmoid bone

12. The lacrimal bone

13. The palatine bone

14. The communications of the orbit

15. The superior orbital fissure

16. The optic foramen

17. The inferior orbital fissure

19. Contents of the orbit Eyeball Extra-ocular muscles Fascia Vessels
Nerves
Retro-orbital fat
NO LYMPHATICS

20. Relations of the orbit

21. Orbital rim

22. Apex of the orbit
Superior orbital fissure
Optic foramen

24. II cranial nerve
III cranial nerve (2 divisions)
IV cranial nerve
V cranial nerve (3 branches of the Ophthalmic division)
VI cranial nerve
Ophthalmic veins (superior and inferior)
Ophthalmic artery

25. Inferior orbital fissure

26. Spaces of the orbit Sub-periosteal space Peribulbar space
Retrobulbar space
Sub Tenon’s space