brief anatomy of sclera is explained here. its helpfull for understanding the basic structure of eye. it just try with minimum knowledge

2. 


Introduction
Gross anatomy
Layers
 Blood supply, drainage and nerve supply

4. INTRODUCTION
• Sclera forms posterior 5/6th of external tunic ,
connective tissue coat of eyeball.
• it continues with duramater and cornea
• Its whole surface covered by tenon’s capsule
• Anteriorly covered by- bulbar conjunctiva
• Inner surface lies in contact with choroid
• With a potential suprachoroidal space in
between

5. Equa
THICKNESS OF SCLERA

6. • Thickness varies with individual, with age
• Thinner- children, elder, F> M
• Thickest posteriorly
• Gradually becomes thinner when traced
anteriorly
• Thin at insertion of extraocular muscle

8. • Anterior scleral foramen
• Posterior scleral foramen
• Tenon’s capsule
• Duramater
• sclerotic ring
• Scleral spur
• Lamina cribrosa

9. • fascial sheath of the
eyeball
• Also known as fascial
bulbi, capsule of tenon,
bulbar sheath
• It’s a thin fibrous
membrane envelops the
eyeball from optic nerve to
the limbus

11. • The scleral spur is an annular structure composed
of collagen in the human eye, a protrusion of
the sclerainto the anterior chamber.
• It is the origin of the longitudinal fibres of the
ciliary muscle and is attached anteriorly to the
trabecular meshwork.
• It is a circular ridge of sclera present on the
innerside of corneoscleral junction
• It is visible on gonioscopy above the ciliary body
band as a white line.

12. • It is mesh like structure present behind the
optic disc in the sclera
• It allows the fibres of the optic nerve to pass
through it and acts as pressure barrier
between the I.O space and retrobulbar space
• The pores in the lamina cribrosa are visible as
lamellar dot sign in advanced glaucomatous
atrophy

14. APERTURE
• 3 sets of aperture
1. Posterior aperture- situates around Optic N.
• Transmit long And short Ciliary N. & vessels
2. Middle aperture- 4 in no.
• Are situated slightly posterior to the equator
• 4 vertex veins passthrough this
3. Anterior aperture- situates 3-4mm away from
limbus
• Ant.ciliary vessels pass through this

15. Layersof
sclera
sclera
episclera
Scleraproper
Lamina
fusca
thin, densevascularised
layer of connective tissue
fibroblasts, macrophages
and
lymphocytes
avascular structure
dense bundles of
collagen fibres.
innermost blends with
suprachoroidal and supraciliary
laminae of the uvealtract.
brownish in colour
presence of pigmented cells.

16. 1. Episcleral Tissue
• thin, dense, vascularised layer of connective tissue
• It covers sclera proper
• Fine fibroblasts, macrophages, lymphocytes are also
present in this layer
2. Sclera proper
• It is an avascular structure
• Consist of bundle of collagen fibres
• The bands of collagen tissue cross each other in all
directions
3. Lamina fusca
• Innermost
• It blends of suprachoroidal &supraciliary laminae of
uveal tract
• It is brownish colour owing to presence of pigmented
cells

17. -Superficial aspect of sclera
-bundles of collagen circumferentially arranged
- rich blood supply anteriorly
-thin, dense, vascularised layer of connective tissue
-It covers sclera proper
-Fine fibroblasts, macrophages, lymphocytes are also
present in this layer
-thickest anterior to the rectus muscle insertions and
becomes progressively thinner toward the back of the
eye.

18. Lamina fusca
• Innermost
• It blends of suprachoroidal &supraciliary
laminae of uveal tract
• It is brownish colour owing to presence of
pigmented cells
• grooves for the passage of ciliary vessels and
nerves (emissary canals)
• attached to the choroid by fine collagen fibers
• Brown color due to melanocytes

19. Sclera proper
• It is an avascular structure
• Consist of bundle of collagen fibres
• The bands of collagen tissue cross each other
in all directions
• deficiency in water-binding substances
accounts for the scleral dull-white color

20. 

Episclera- anterior and posterior ciliary arteries
Scleral stroma- relatively avasculature structure

22. 

Episcleral collecting veins
Vortex veins
Anterior ciliary veins

23. 


Rich in nerve supply
Anterior sclera- long posterior ciliary nerves
which pierce it 2-4mm from the limbus to form a
plexus
Posterior sclera- short posterior ciliary nerves


24. 

FUNCTIONS
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.

25. EMBRYOLOGY
• Sclera -> derived from mesenchyme-> derived
from neural crest