Detailed explanation of anatomy of sclera

1. By
Dr Satish S Hadimani
Dept of shalakya tantra
SGR Ayurved Mahavidyalaya,
Solapur

3. Sclera
 Introduction
 Gross anatomy
 Layers
 Blood supply, drainage and nerve supply

4. Introduction
 Its dense connective tissue that accounts for five sixths of the
outer coat of the eyeball
 Sklera mannix- hard membrane
1. Protects intraocular components from trauma, light, and
mechanical displacement
2. Withstands the considerable expansive force generated by
the intraocular pressure maintaining the shape of the globe
3. Provides attachment sites for the extraocular muscles.

5. Optic nerve
Equator=0.4-0.5mm
Insertions=0.6mm
Thickness of sclera

6. Insertion Of Rectus Muscle

7. Tenons capsule
• Fascial sheath of
the eyeball
• And it’s connection
with sclera and
optic nerve

8. Ant scleral foramen & Scleral spur

9. Post scleral foramen & lamina
cribrosa

10. Apertures

12.  Lamina cribrosa:
 It is a sieve-like sclera from which the fibres of the optic
nerve pass.
 Scleral apertures(emissaria):
Sclera has three sets of apertures :
 Posterior aperture : situated around the optic nerve.
 Middle apertures: situated 4-7mm posterior to the equator.
 Anterior aperture: situated 3-4mm away from the limbus

13. Microscopic structure
Histologically, sclera consist of following three layers
 Episcleral tissue
 Sclera proper
 Lamina fusca

14. Episclera
 Superficial aspect of sclera
 bundles of collagen circumferentially arranged
 rich blood supply anteriorly
 thickest anterior to the rectus muscle insertions and
becomes progressively thinner toward the back of
the eye.

15. Scleral stroma
 bundles of collagen fibers with fibroblasts,
melanocytes, elastic fibers, proteoglycans, and
glycoproteins
 variability in collagen fiber diameter, interlacing in
bundles of collagen, and relative deficiency in
water-binding substances accounts for the
scleral dull-white color.

16. Lamina fusca
 Brown colour due to melanocytes
 grooves for the passage of ciliary vessels and nerves
(emissary canals)
 attached to the choroid by fine collagen fibers

17. Blood supply
 Episclera-anterior ciliary arteries
posterior ciliary arteries
 Scleral stroma-relatively avasculature
structure

19. Venous drainage
 Episcleral collecting veins
 Vortex veins
Anterior ciliary veins

20. Nerve supply
 Rich in nerve supply
 Anterior sclera- long posterior ciliary nerves
 Posterior sclera- short posterior ciliary nerves
 Pain- inflammation, stretching due to oedema and
movement of eye

21. Thank you