Download Basic Ocular Anatomy

Basic Ocular
Anatomy
That Won’t Put You to Sleep
Leslie Gallagher, OD, FAAO
Lifetime Eye
Holton, KS
What’s In It For Me?

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Better understanding
of duties
Better patient
communication
Increased enjoyment
of work
Increased
responsibilities (pay)
The Eye From 10,000 Ft
 Like
an
onion…layers
 Not a perfect
sphere
 Examine the eye
from front (anterior)
to back (posterior)
Lids, Lashes
 Moveable
folds of
skin
 Blinks 4-6/minute
 Protects the eye
 Spreads tears
(windshield wiper)
 Muscles control lid
position/function
Ptosis
Blepharitis
Trichotillomania
Latisse
Hordeolum…Stye
The parts the are visible from
outside
 Conjunctiva/sclera
 Iris
 Pupil
Cornea on the
outside but not
visible
Sclera (conjunctiva)
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The white of the
eyes
All variations of
normal
Bulbar conjunctiva
covers sclera
Mucus membrane
Inner & outer
corners are
“canthi”
What in the world is a
caruncle?
Pinguecula
Pterygium
Subconjunctival Heme
Not to be confused with..
Pink Eye (conjunctivitis)
Cornea
Cornea
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Clear windshield
Where is meets the
sclera is called the
“limbus”
70% refractive power
of the eye
5 layers (epithelium,
Bowman’s, stroma,
Descemet’s, &
endothelium)
Layer’s of the Cornea
 Epithelium-
painful when injured; heals
very quickly without scarring
 Bowman’s- doesn’t regenerate; scars
 Stroma- 90% cornea thickness; scars
 Descemet’s- transparent, elastic
 Endothelium- single layer of cells;
regulates (de-)hydration; does NOT
regenerate
Corneal abrasions
Corneal Foreign Bodies
Corneal laceration
LASIK
The Iris
 Separates
front/back part of eye
 Colored part of the eye (1yr of age)
 Center aperture/hole is the pupil
 Regulates the amount of light to
provide for best image
Iris Coloboma
Behind the Iris…lens
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Transparent
Bi-convex
10 mm diameter
4mm thick
Attached to ciliary
body by zonules
Contraction/relaxati
on causes focusing
or accomodation
What is a cataract?
Vitreous
 Clear
jelly-like
substance
 Fills the back 2/3 of
the eye
 Gives shape to the
eye
Vitreous Detachment
Floaters
Back to the “Onion”
 Sclera
 Choroid
 Retina
Parts of the Retina
 Innermost
layer
inside globe
 Contains the
photoreceptors
(rods & cones)
 Cones can discern
more than 150
colors
 Rods-
function
best in dim
lighting
 Damage to
rods result in
night blindness
Macula
 Central
4.5 mm
 Responsible for
central vision
 Only cones in
fovea (centermost
area of macula)
Macular Degeneration
Macular Hole
Optic Nerve
 2nd
cranial nerve
 25-30 mm long
 Transmits impulses
from eye to brain
 Physiological blind
spot
 Dr. looks at for
many conditions
WAKE UP!!!
Blood Vessels
Extra ocular Muscles
6
muscles
 Insertion is covered
by conjunctiva
 Congenital
 Acquired- like
stroke victims
Summary
 By
understanding
basic ocular
anatomy



Better patient
communication
Better
communication
with Dr.
Increased
responsibility