Nursing NAIHS

1. Eye
Maj Dr Rishi Pokhrel
MBBS, MD
Dept of Anatomy, NAIHS

8. Introduction
• Peripheral organ of vision
• Present in anterior part of orbit
• 1 inch in diameter
• Orbital fascia and bulbar fascia

9. Orbital fascia and bulbar fascia

11. .

12. FASCIA BULBI (Tenon's capsule)
• It is a thin membrane which envelops eyeball
from optic nerve to ciliary region;
• allows eyeball to move freely
• smooth inner surface pierced by vessels and
nerves
• fuses with sheath of optic nerve and sclera
• lower part of membrane thickens into
suspensory ligament (checks ligaments) which
attaches to zygomatic arch and lacrimal
bones.

13. Structure

14. Structure
• Outer fibrous coat
is composed of
– Sclera
– Cornea
• Middle vascular
coat comprises
– Choroid
– Ciliary body
– Iris
• Inner nervous coat
consists of
– Retina

16. CORNEA
• half inch wide convex and
transparent layer.
• 5 layered
• Anterior chamber
separates it from iris.
• avascular, nourished by
lymph and aqueous
humor
• rich nerve supply.
• Its junction with sclera is
limbus.

17. SCLERA
• This visible white part of
the eye is covered with
conjunctiva.
• made up of dense fibrous
tissue.
• It provides attachments to
tendons of recti and
obliqui.
• It is pierces by numerous
nerves and vessels.

18. CHOROID
• It lines sclera and
separates it from
retina.
• consists of pigmented
tissue containing nerve
plexuses, network of
capillaries, arteries and
superficially veins.

25. CILIARY BODY
• connects choroid with
iris.
• made up of ciliary
processes (internally) and
ciliary muscle
(externally).

26. CILIARY MUSCLE
• muscular ring placed deep
to anterior part of sclera.
• made up of radial and
circular fibres.
• brought into action during
accommodation e.g. it
slackens suspensory
ligament of lens thus
making it move convex as
is required for near vision.

27. IRIS
• placed b/w lens and
cornea
• circular, colored and
contractile curtain.
• central aperture – pupil
• made up of smooth
muscle called sphincter
pupillae and dilator
pupillae.
• Decrees and increase the
size of pupil - aperture

28. RETINA
• Light sensitive layer
• 10 layers
• Cells - Rods and cones
• two components.
– Pigmented layer (external layer) is attached to
choroid and continues over ciliary body to iris.
– Retina proper (internal layer) is in contact with
vitreous. Ora serrata divides it into posterior optic
part and anterior ciliary part.
• Ora serrata - wavy border behind the ciliary body.

29. RETINA
• Macula lutea- at posterior pole of eyeball on
retinal is a small yellowish spot.
– It presents fovea centralis - cones

30. ROD CONE

31. • Optic disc
– point where optic nerve
fibers converge to leave
eyeball.
– 1 mm below and 3 mm
medial to posterior pole.
– Its circumference is raised
while its centre is
depressed called optic
cup.
– The disc is the blind spot
of eye as it lacks nervous
elements.

32. LENS
• transparent and circular,
b/w vitreous and iris
• Biconvex, 10 mm in
diameter and 4 mm
thick.
• Ciliary muscle
contraction -> slackening
of suspensory ligament -
> thickening of lens ->
near vision

33. • ANTERIOR CHAMBER
• It is the space between cornea
anteriorly & iris and central
part of lens posteriorly
• POSTERIOR CHAMBER
• It is behind iris and suspensory
ligament and adjoining part of
lens posteriorly. The two
chambers communicate
through pupil; filled with a
clear fluid called aqueous
humor.

34. • VITREOUS HUMOUR
(Vitreous body)
• transparent and jelly
like substance that
fills posterior 4/5 of
eyeball.
• enclosed in a
transparent
membrane (hyaloid
membrane)

35. CLINICAL ANATOMY
Cataract
• progressive condition of lens
characterized by loss of
transparency.
• a gray-white opacity in the lens.
• Congenital cataracts are usually
hereditary but may be caused by
viral infection during first
trimester of gestation.
• Senile cataracts are
uncomplicated cataracts of old
age. Vision is lost if cataracts are
not treated.

36. Retinal detachment
• separation of retina
from choroid.
• The retina does not
contain sensory nerves;
thus condition is
painless.
• D begins at the thin
peripheral edge of
retina and extends
gradually beneath
thicker central areas.
• is not checked it results
in blindness.

37. Corneal grafting (keratoplasty)
• This surgical
procedure of
transplantation of
cornea is performed
to improve vision in
corneal scarring,
distortion or
perforation.

38. Glaucoma
• elevated intraocular pressure because of
obstruction of outflow of aqueous humour.
Glaucoma may be:
– Acute (narrow angle)
– Chronic (wide angle) glaucoma

39. Corneal reflex
• protective mechanism for eye where eyelids
close when cornea is touched.
• mediated by ophthalmic division of 5th cranial
nerve (sensory) and 7th cranial nerve (motor).
• This reflex may be used as a test of integrity of
those nerves.

40. queries

41. Ant Epithelium
Bowman’s membrane
Substantia propria (Stroma)
Descemet’s membrane
Post Epithelium / Endothelium
Layers of Cornea

42. Uvea
• Vascular layer
• 3 Parts
– Choroid
– Ciliary body
– Iris

43. Retina

44. Introduction
• Neural Photoreceptor layer
• Development
– Optic vesicle - cup
– Outer layer- Pigment
– Inner layer- Neural
– Detachment

45. ROD CONE

46. Layers
• Ten layers– Outside in
– Retinal Pigment epithelium
– Outer segment & Inner segment - Photoreceptors
– External Limiting membrane
– Outer Nuclear
– Outer Plexiform
– Inner Nuclear
– Inner Plexiform
– Ganglion cell
– Optic nerve fibre
– Internal Limiting membrane
• Mnemonic: Please Reply MY New Post, Never Pray God
For Money
– NB- Outside in- ? Dir light/Impulse

48. Layers Of The Retina
10
9
8
7
6
5
4
3
2
1

49. 1. Retina contains photosensitive cells.
The outer limit of the retina is the Pigmented Epithelium (PEp)
1. Choroid (Ch) is a highly vascular layer containing melanocytes and
separated from the retina by the epithelial basement membrane
(Bruch’s membrane)
3. Sclera (S) consists of dense fibroelastic connective tissue
3 Coats Of The Eye
s