Scleral Microstructure

1. GEORGE COLLEGE OF
MANAGEMENT AND SCIENCE
NAME: ALMAAZ AHMED
STREAM: B.OPTM
SEM.: 2nd SEM
ROLL: 16401719005
SUBJECT CODE: BO-203
SUBJECT NAME: ANATOMY(OCULAR)
SUBJECT MENTOR: DR. KAUSHIK SINHA
TOPIC: SCLERAL MICROSTRUCTURE

2. INTRODUCTION
• Sclera constitutes more
than 80% of the eye wall.
• It forms the posterior
opaque fifth-sixth part of
the external fibrous tunic
of the eyeball.
• It’s whole outer surface is
covered by Tenon’s
Capsule.
• It’s inner surface lies in
contact with the choroid.

3. SCLERAL APERTURES
• It has three sets of apertures:
1. Posterior apertures are situated around the optic
nerve and transmit long and short ciliary nerves
and vessels.
2. Middle apertures are situated 4-7 mm posterior
to the equator.
3. Anterior apertures are situated 3-4 mm away
from the limbus and transmit anterior ciliary
vessels and ciliary nerves.

4. MICROSTRUCTURE OF
SCLERA
It consists of three
layers:
1. Episcleral Tissue
2. Scleral Proper
3. Lamina Fusca

5. EPISCLERAL TISSUE
• It is a thin, dense vascularised layer of the
connective.
• It covers the sclera proper.
• It becomes continuous with the Tenon’s
capsule.
• The capillary network present in the anterior
part becomes prominent during inflammation
giving rise to ciliary flush.

6. SCLERA PROPER
• It is an avascular structure which consists of
dense bundles of collagen fibres crossing each
other in all directions.
• This arrangement makes the sclera opaque.
• Mucopolysaccharides are present in the
interfibrillar space of the collagen fibres.
• Few fibroblasts are also present in this layer.

7. LAMINA FUSCA
• It is the innermost part of sclera.
• It blends with suprachoroidal and supraciliary
lamina of the uveal tract.
• It is brownish in colour owing to the presence
of pigment cells.

8. NERVE SUPPLY OF THE SCLERA
• The sclera is supplied by branches from the long
ciliary nerves anteriorly and short ciliary nerves
behind the equator.
FUNCTIONS:
• It is the opaque, fibrous, tough, protective layer of
the eye.
• It is directly continuous with the cornea in front
and with the sheath covering the optic nerve
behind.
• It forms the entire visible white exterior of the
eye.