The document provides information about the anatomy and structure of the eye, how vision works, common eye conditions such as cataracts and glaucoma, and tips for eye care including eating a healthy diet, wearing protective eyewear, and exercising your eyes. It describes the parts of the eye like the cornea, iris, pupil, lens, retina, and optic nerve and how light enters the eye and is focused onto the retina to allow vision. Common eye defects and diseases addressed include myopia, hyperopia, astigmatism, conjunctivitis, and styes.
14. How do you see?
Looking to an object, the light rays
reflected from the object enter
the eye. The light reflected to
cornea and passes through the
aqueous humor, and the pupil to
the lens.
15. How do you see?
As the light travels to our eyes, the lens focuses
the image of the object on the retina. The object
in the retina is inverted. As the image is formed
the optic nerves send the message to the brain.
It is the brain that interprets and corrects the
inverted image into an upright position.
16. Common Eye Ailments
1. Conjuctivities- (sore eyes)
commonly caused by viral
infection, but bacterial
infections, allergies, other
irritants and dryness are also
common etiologies for its
occurrence. Both bacterial and
viral infections are contagious.
Commonly, conjunctival
infections are passed from
person to person, but can also
spread through contaminated
objects or water
17. Common eye ailments
2. Sty - results from an
infection of the oil glands
of the eyelid (meibomian
glands) that help to
lubricate the eyeball. The
infection occurs after these
glands have become
clogged. A sty also may
arise from an infected hair
follicle at the base of an
eyelash.
18. Common Eye Defects
•Cataracts
- do not have to change
your life! They are a
normal part of aging and
can be treated. People
regain most or all vision,
and continue to do things
they love to do. A cataract
is a gradual clouding of
the clear lens in the eye
which results in a blurry
or hazy image, and a
sensitivity to light.
• To correct it, an
ophthalmic surgeon
removes the
damaged lens and
replaces it with a
clear, artificial one.
Surgery is short, and
you can go home
the same day and
resume normal
activities shortly
after.
19. • A cataract is a progressive, painless clouding of the
natural, internal lens of the eye. Cataracts block light,
making it difficult to see clearly. Over an extended
period of time, cataracts can cause blindness. They're
often related to growing older, but sometimes they
can develop in younger people
20.
21. How Cataracts Affect Your Vision
• In a normal eye, light enters and passes through the lens. The
lens focuses that light into a sharp image on the retina, which
relays messages through the optic nerve to the brain. If the
lens is cloudy from a cataract, the image you see will be
blurry. Other eye conditions, such as myopia, cause blurry
vision, too, but cataracts produce some distinctive signs and
symptoms.
22. Cataract Symptom: Blurry Vision
• Blurry vision at any distance is the most common
symptom of cataracts. Your view may look foggy,
filmy, or cloudy. Over time, as the cataracts get
worse, less light reaches the retina. People with
cataracts may have an especially hard time seeing
and driving at night.
23. Cataract Symptom: Double Vision
• Sometimes, cataracts can cause double vision (also
known as diplopia) when you look with one eye. This
is different from the double vision that comes from
the eyes not lining up properly. With cataracts,
images appear double even with one eye open.
24.
25. Cataract Symptom: Color Changes
• Cataracts can affect your color vision, making some
hues look faded. Your vision may gradually take on a
brownish or yellowish tinge. At first, you may not
notice this discoloration. But over time, it may make
it harder to distinguish blues and purples.
26. What Causes Cataracts?
• The exact cause of cataracts is unknown. While the risk grows
as you get older, these factors may also contribute:
• Diabetes
• Smoking
• Excess alcohol use
• Eye Injury
• Prolonged use of corticosteroids
27. Common Eye Defects
•Glaucoma
- is a leading cause
of blindness. Anyone
can develop
glaucoma, with most
people not knowing
they have it. You are
at greater risk when:
28.
29. Common Eye Defects
• Graves Disease
- is typified by an apical
enlargement of the eye
muscles which
stimulates other
fibroblasts. Fluid is
drawn into the muscle
and stored, eventually
leading to the
development of scar
tissue. In addition, the
swelling of the muscles
pushes the eye forward
causing it to protrude.
30. Common Eye Defects
• Graves Disease
-As a result patients may
have trouble closing
their eyes, which causes
drying, irritation and
increased inflammation.
Increased effort to
bring the eyelids
together may result in a
frown, or swollen
muscles may compress
the optic nerve leading
to loss of vision if
treatment is not sought
early on.
31. Common Eye Defects
• Low Vision
• There are a variety of disorders that
can affect the eye and the visual
system causing low vision. These are:
birth defects, injuries, certain diseases
of the body and aging. The most
common cause of low vision is
macular degeneration. Macular
degeneration is a disease of the retina
or the inner layer of the eye that
senses light and allows you to see.
• Reduced central or reading vision is
the most common type of low vision.
Other types of low vision are reduced
side vision (peripheral), and loss of
color vision. Your eyes also might lose
the ability to adjust to light, contrast
or glare. Different types of low vision
may require different types of aids.
32.
33. Common Eye Defects
•Astigmatism
This defect is when the light
rays do not all come to a single
focal point on the retina,
instead some focus on the
retina and some focus in front
of or behind it. This is usually
caused by a non-uniform
curvature of the cornea. A
typical symptom of astigmatism
is if you are looking at a pattern
of lines placed at various angles
and the lines running in one
direction appear sharp whilst
those in other directions
appear blurred. Astigmatism
can usually be corrected by
using a special spherical
cylindrical lens; this is placed in
the out-of-focus axis.
34. Common Eye Defects
•Hyperopia (farsighte
dness) This is a defect of vision
in which there is difficulty with
near vision but far objects can
be seen easily. The image is
focused behind the retina
rather than upon it. This occurs
when the eyeball is too short or
the refractive power of the lens
is too weak.
• Hyperopia can be corrected by
wearing glasses/contacts that
contain convex lenses.
35. Common Eye Defects
•Myopia
(nearsightedness) This is a
defect of vision in which far
objects appear blurred but
near objects are seen clearly.
The image is focused in front
of the retina rather than on it
usually because the eyeball is
too long or the refractive
power of the eye’s lens too
strong. Myopia can be
corrected by wearing
glasses/contacts with concave
lenses these help to focus the
image on the retina.
36. Common Eye Defects
•Strabismus (/str b zm s/,əˈ ɪ ə
from Greek strabismós[1]
), also known
as squint andheterotropia (and
including the two variants cross-
eye and walleye),[
- a condition in which the eyes are not
properly aligned with each other.
Strabismus can present as manifest
(heterotropia) or latent (heterophoria)
varieties, and can be either a disorder
of the brain in coordinating the eyes,
or of the power or direction of motion
of one or more of the relevant
muscles moving the eye
37. Common Eye Defects
• A squint is a condition where the eyes do not look
together in the same direction. While one eye looks
straight ahead, the other eye turns to point inwards,
outwards, upwards or downwards. Squints are common
and affect about 1 in 20 children. You might even spot
that your baby has a squint. Most squints develop before
preschool age, usually by the time a child is three years
old. Sometimes squints develop in older children, or in
adults.
38.
39. How to take care of our eyes
• Eat lots of fruits and
veggies! Carrots, loaded
with beta carotene are
especially helpful in
maintaining healthy
eyes. That's because
beta carotene is an
antioxidant that reduces
the risk of macular
degeneration.[1]
40. How to take care of our eyes
• Avoid wearing contact
lenses for more than 19
hours. This can cause
permanent sight damage
as well as extreme
discomfort to your eyes.
Don't wear glasses too
long either. Especially 3-
D glasses!
41. How to take care of our eyes
• Never sleep with your contact lenses in
unless specifically instructed to do so.
• Your eyes need regular supplies of
oxygen, and lenses block the flow of
oxygen to the eyes, especially during
sleep. So doctors recommend a normal
period of break for your eyes during the
night.
42. How to take care of our eyes
• Avoid wearing your contact
lenses when swimming. Your
lenses could easily slip off your
ideas when they come in
contact with the surface area of
the water. If you are wearing
goggles, your contact lenses
may be used while swimming.
43. How to take care of our eyes
• Use allergen-reducing eye
drops sparingly. Using an
allergen-reducing eye drop
during allergy season to
'get the red out' and sooth
itchiness may help on a
limited basis, but chronic
daily use can actually
make the problem worse.
44. • Allergen-reducing eye drops work by
constricting the blood flow to the cornea,
thereby depriving it of oxygen. So while
your eyes don't feel inflamed and itchy
anymore, they're actually not getting any
oxygen from blood. That's not ideal.
• Using redness-relieving eye drops
chronically will cause more redness in your
eyes. Your body gets so accustomed to the
chemicals in the eye drops that they no
longer work effectively.
• Read the labels of eye drops carefully;
many drops cannot be used while wearing
contacts.
45. How to take care of our eyes
• Wear UV protective
sunglasses. Get polarized
lenses, NOT just darker
lenses. The lenses that only
make the world darker will
just make your pupils dilate
and don't do a thing to
stop the UV rays.
46. • Prolonged exposure to UV rays can harm your
eyesight, protection in youth can help prevent loss of
eyesight in later years. Exposure to UV rays has been
linked to cataracts, macular degeneration,
pingueculae and pterygia, harmful conditions for the
eyes.
• Since the damage to eyes from UV rays builds up over
a lifetime, it's important to shield children from
harmful rays. Make sure your children wear hats and
protective glasses when they are out in the sunlight
for prolonged periods.
• Be sure to wear sunglasses even if you're in the shade.
Even though shade lessens UV and HEV exposure
significantly, you're still exposing your eyes to UV rays
reflected off of buildings and other structures.
47. How to take care of our eyes
• Try not to spend so
much time looking at
your computer
screen.It is a good time
to give your eyes a
break, since you're not
doing anything
too important.)
48. • it may cause eye strain and
dry eyes.The glare from
computer screens causes
muscle fatigue in the eyes,
either from being too bright
or too dark.
• People blink less when
they're looking at a screen,
causing drier eyes. Make a
conscious effort to blink
every 30 seconds when
you're sitting down and
looking at your computer
screen to combat dry eyes.
49. How to take care of our eyes
• Wear goggles when
appropriate. Be sure to
wear goggles or other eye
protective wear when
working with chemicals or
any place with harmful
airborne particulates.
• Minimize the transmission
of harmful particulate
matter into eye region.
50. How to take care of our eyes
•Exercise your
eyes, and also
be sure
to relax them.
51. • Try focusing your eyes on objects that are near to you,
then objects that are far away. Repeat this process
multiple times.
• Sit down, place your elbows on your hips, close your
eyes and bring your closed eyes down, resting them
on your palms. Keep your palms covering your eyes for
10 seconds. Open your eyes and repeat as necessary.
• Stretch your arm out and place your thumb in the
hitchhiker position. Focus your vision on your thumb
while you slowly bring your outstretched arm closer to
your body, until your thumb is about five inches from
your face. Slowly zoom the thumb back to its original
position, focusing on it with your eyes all the while.
52. How to take care of our eyes
• Do not read in dim
light. Reading in dim
light can cause eye
strain but will not
damage your eyes. If
your eyes feel tired,
stop for a while and
take a break.
53. How to take care of our eyes
• Do not look at a
bright light directly.
Never focus your
eyes on the sun
directly, as it can
damage your eyes.
54. First Aid for Eye Injuries
• If you wear contact lenses, remove them immediately if y
ou get chemicals in your
eyes. Keeping them in your eyes may hold the chemical a
gainst the cornea, causing unnecessary damage and pain.
• If you suspect chemicals have entered your eye, begin flus
hing it immediately
with cool water and continue to do so for approximately
15 minutes.
• Seek immediate medical attention by dialing 911 or going
to the nearest
emergency room. If possible, take the container of the off
ending substance with
you so that you can tell your doctor what you have been
exposed to.
55. First Aid for Eye Injuries
• First Aid When You Have Something in Your Eye
• If you have an object in your eye, do not irritate your eye
by rubbing it. You may try to remove the particle if it is not
embedded in the eye. But, follow these first aid tips first:
• First wash your hands thoroughly with soap and water. This will
prevent further contamination or infection.
• Try flushing the eye with water. Using your finger and thumb,
gently pull the upper eyelid down over the top of the lower
eyelid. This should cause tearing and flush the object out. You
may need to repeat this several times.
• If you can see the object, you may try to remove it from your eye
with a washcloth. Gently lift the upper or lower eyelid, and use a
clean, wet washcloth to wipe the object away. If this does not
work, seek immediate medical attention.