ANATOMY OF EYE

1. ANATOMY OF EYE

2.  THE EYE IS SITUATED IN THE ORBITAL CAVITY OF
THE SKULL
 IT IS WELL PROTECTED BY THE BONY WALLS OF THE
ORBIT
 ORBIT ALSO CONTAINS MUSCLES OF EYEBALL, THEIR
NERVES, BLOOD VESSELS, AND LACRIMAL GLAND

3. STRUCTURE OF THE EYEBALL
• WALL OF THE EYEBALL
• REFRACTIVE MEDIA

4. WALL OF THE EYEBALL
 OUTER LAYER(FIBROUS COAT) : SCLERA AND
CORNEA
 MIDDLE LAYER(VASCULAR COAT) : CHOROID,
CILIARY BODY AND IRIS
 INNER LAYER(NERVOUS COAT) : RETINA

9. SCLERA AND CORNEA
• SCLERA FORMS THE OUTERMOST LAYER OF THE EYEBALL
• THE ANTERIOR 1/6TH PART OF THE SCLERA IS TRANSPARENT AND
IS KNOWN AS CORNEA
• LIGHT RAYS PASS THROUGH THE CORNEA TO REACH THE RETINA

10. FUNCTIONS OF SCLERA
• IT PROVIDES PROTECTION TO THE DELICATE
STRUCTURES WITHIN THE EYE
• IT RESIST INTRAOCULAR PRESSURE
• IT MAINTAINS THE SHAPE OF THE EYEBALL
• THE SMOOTH EXTERNAL SURFACE ALLOW EASY EYE
MOVEMENT

11. CHOROID
• CHOROID IS A THIN PIGMENTED MEMBRANE, DARK
BROWN IN COLOR WHICH IS SITUATED IN BETWEEN
SCLERA AND RETINA

12. CILIARY BODY
• IT IS THE CONTINUATION OF CHOROID CONSISTING OF SMOOTH MUSCLE FIBRE
I.E. THE CILIARY MUSCLE
• IT CONTAINS SUSPENSORY LIGAMENT FOR ATTACHING THE LENS IN POSITION
• IT HELPS IN ACCOMMODATION BY ADJUSTING THE THICKNESS OF THE LENS

13. IRIS
• IRIS IS THE PIGMENTED MEMBRANE SURROUND THE PUPIL
• IT ARISES FROM THE MARGIN OF CILIARY BODY AND FORMS A DARK
CENTERED OPENING CALLED PUPIL
• THE SPACE BETWEEN CORNEA AND THE LENS IS THE ANTERIOR SEGMENT
• IT IS FURTHER DIVIDED INTO TWO PARTS BY THE IRIS
• THE SPACE BETWEEN THE IRIS AND THE CORNEA IS THE ANTERIOR
CHAMBER
• THE SPACE BETWEEN THE IRIS AND THE LENS IS THE POSTERIOR
CHAMBER
• THEY ARE FILLED WITH AQUEOUS HUMOR

14. RETINA
• IT IS A THIN DELICATE LAYER CONTINUOUS POSTERIORLY WITH OPTIC NERVE
• THE OUTER SURFACE OF THE RETINA, FORMED BY THE PIGMENT CELLS, IS ATTACHED
TO THE CHOROID
• ITS INNER SURFACE IS IN CONTACT WITH HYOID MEMBRANE OF THE VITREOUS
• THE SMALL AREA OF THE RETINA WHERE THE OPTIC NERVE LEAVES THE EYE IS THE
OPTIC DISC OR THE BLIND SPOT
• RETINA HAS THREE PARTS
1) OPTIC
2) CILIARY
3) IRIDIAL
• THE OPTIC PART CONTAINS NERVOUS TISSUE AND IT IS SENSITIVE TO LIGHT
• IT EXTENDS FROM THE OPTIC DISC TO THE CILIARY BODY
• THE THIN NON NERVOUS AND NON SENSITIVE LAYER COVERS THE CILIARY BODY AND
IRIS IS CALLED CILIARY AND IRIDIAL PART OF RETINA

15. • LATERAL TO THE OPTIC DISC A DEPRESSION CALLED
MACULA LUTEA
• THE CENTER OF MACULA IS AGAIN DEPRESSED TO FORM
FOVEA CENTRALIS
• IT CONTAINS CONES ONLY AND IS THE SITE OF MAXIMUM
ACUITY OF VISION
• THE RODS AND CONES ARE THE RECEPTORS OF LIGHT
AND SIGHT
• THESE CELLS CONTAIN PHOTOSENSITIVE PIGMENTS
INVOLVED IN THE CONVERSION OF LIGHT RAYS INTO
NERVE IMPULSES

19. • INTERFERENCE WITH DRAINAGE OF AQUEOUS HUMOR
RESULTS IN AN INCREASE IS INTRAOCULAR PRESSURE
(GLAUCOMA)
(NORMAL IOP : 10-20 MMHG)
• THIS LEADS TO ATROPHY OF RETINA ,LEADING TO BLINDNESS

31. THANK YOU