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Tamil
Nadu State Blindness Control Society |
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Cataract
What
is a cataract?
A
cataract is a cloudy area in the lens of the eye. The lens helps
focus light on the retina at the back of the eye. It is located
behind the iris (the colored part of the eye). As a cataract grows
larger over time, the cloudiness worsens and causes vision problems.
How
does it occur?
Most
cataracts occur naturally as people get older. What causes cataracts
is not known, but many factors may contribute to their formation,
such as:
Cataracts
don't spread from one eye to the other, but many people have
cataracts in both eyes.
What
are the symptoms?
The
symptoms of a cataract include:
How
is it diagnosed?
The
symptoms of a cataract develop slowly and are painless. The
condition may go unnoticed and undiagnosed for a long time. It is
often first diagnosed during a routine eye exam.
How
is it treated?
If
a cataract is not interfering with your lifestyle or work, your
doctor may suggest changing your glasses or using brighter lights to
help you read.
If
the cataract is seriously affecting your vision and cannot be helped
with glasses or contact lenses, a surgeon may need to remove the
lens. This type of surgery is called cataract extraction surgery.
After the lens is removed your surgeon may put a new plastic lens in
your eye (intraocular lens implantation). If you do not have a new
lens put in, you will need to wear contact lenses or cataract glasses.
How
long will the effects last?
Decreased
vision from cataracts is reversible and will last until it is
corrected with glasses, contact lenses, or surgery. Surgery to remove
cataracts is highly successful in restoring vision.
What
can be done to help prevent cataracts?
You
may reduce the risk of damaging your eyes and in turn reduce the
risk of developing cataracts by wearing goggles or safety glasses at
work or during recreation where your eyes could be injured. Wearing
glasses with a UV coating that protects your eyes from sunlight might
prevent or delay some types of cataracts, but this is not proven.
If
you are a woman and plan to have a baby, make sure you have had a
German measles (rubella) shot at least 3 months before you become
pregnant. If you have German measles while you are pregnant, your
baby's eyes should be checked by an eye care professional soon after
birth. A baby can develop cataracts if you had German measles while
you were pregnant.
Viral
or Bacterial Conjunctivitis
What
is conjunctivitis?
Conjunctivitis
is inflammation of the conjunctiva. The conjunctiva is the clear
membrane that lines the eyelids and covers the white of the eye.
How
does it occur?
Conjunctivitis
can be caused by many things, including infection by viruses or
bacteria. Viruses that cause colds may lead to conjunctivitis. Some
bacteria that cause conjunctivitis are chlamydia, staphylococci, and
streptococci. Severe conjunctivitis, such as that caused by
gonococci, can cause blindness.
What
are the symptoms?
Symptoms
may include:
-
itchy
or scratchy eyes
-
Redness
- Sensitivity
to light
- Swelling
of eyelids
- Watery
discharge
- Discharge
of pus.
How
is it diagnosed?
Your
doctor will ask about your medical history and if you have been near
someone who has conjunctivitis. He will examine your eyes. He or she
will also check for enlarged lymph nodes near your ear and jaw. If
the conjunctivitis appears to be caused by bacteria, he may get lab
tests of a sample of the pus to see what type of bacteria are present.
How
is it treated?
Like
a cold, viral conjunctivitis will usually go away on its own, even
without treatment. However, your doctor may prescribe eyedrops to
help control your symptoms. Antihistamine pills may also relieve the
itching and redness.
If
you have bacterial conjunctivitis, your health care provider will
prescribe antibiotic eye drops. You can also help your eyes get
better by washing them gently to remove any pus or crusts. Then dry
them gently with a clean towel.
If
you wear contact lenses, you will need to stop wearing them until
your eyes are healed. The combination of contacts and conjunctivitis
may damage your cornea (the clear outer layer on the front of your
eye) and cause severe vision problems.
How
long will the effects last?
Viral
conjunctivitis usually gets worse 5 to 7 days after the first
symptoms. It can improve in 10 days to 1 month. If only one eye is
affected at first, it may take up to 2 weeks for the other eye to be
affected. Usually, if both eyes are affected, the first eye has worse
conjunctivitis than the second.
Bacterial
conjunctivitis should improve within 2 days after you begin using
antibiotics. If your eyes are not better after 3 days of antibiotics,
call your health care provider.
How
can I prevent conjunctivitis?
To
keep from getting conjunctivitis from someone who has it, or to keep
from spreading it to others, follow these guidelines:
-
Wash
your hands frequently. Do not touch or rub your eyes.
-
Never
share eye makeup or cosmetics with anyone. Also, if lab results show
that you have conjunctivitis, throw out eye makeup you have been using.
- Never
use eye medicine that has been prescribed for someone else.
- Do
not share towels, washcloths, or sheets with anyone. If one of your
eyes is affected but not the other, use a separate towel for each eye.
- Avoid
swimming in swimming pools if you have conjunctivitis.
When
should I consult a doctor?
Consult
if:
Diabetic
Retinopathy
What
is diabetic retinopathy?
Diabetic
retinopathy is an eye problem caused by diabetes mellitus. It
affects the retina, which is light-sensitive tissue at the back of
the eye. Retinopathy occurs when diabetes damages the tiny blood
vessels in the retina. This damage can lead to problems with your
vision, including blindness. However, you may be able to prevent
severe vision problems if:
How
does it occur?
High
blood sugar levels damage small blood vessels. The weakened blood
vessels may break and leak fluid and blood. Also, new abnormal blood
vessels may grow. These new blood vessels can bleed, cause cloudy
vision, and destroy the retina.
The
longer you have had diabetes, the more likely you are to have retinopathy.
What
are the symptoms?
Diabetic
retinopathy begins before you have any symptoms. As the problem gets
worse, you may have:
How
is it diagnosed?
The
doctor will look at your eyes with a special light. He or she will
be able to see inside your eyes and look for signs of retinopathy.
Your doctor may refer you to an eye specialist (an ophthalmologist or optometrist).
How
is it treated?
Early
treatment before the retina has been badly damaged is the most
successful in reducing vision loss from this disease.
Your
eye surgeon may use a laser to seal leaking blood vessels. The
surgeon may also use a laser to destroy abnormal blood vessels.
If
you have had bleeding into the clear gel (vitreous) that fills the
inside of the eye, the eye surgeon may remove the gel. The gel will
be replaced with a clear fluid. This procedure is called a vitrectomy.
How
long will the effects last?
As
long as you have diabetes, there is a chance you will have
retinopathy. However, careful control of your blood sugar levels will
help delay and possibly prevent vision loss.
You
may need to be treated more than once for retinopathy. Have your
eyes checked regularly to make sure you get treatment when you need it.
Retinopathy
can cause the retina to become detached. This means the retina is
pulled away from the back of the eye. If this happens, you need to
see your doctor for urgent treatment to reduce the chance of
permanent vision loss. Consult your doctor right away if you start
seeing dark spots, floaters, or light flashes or your vision is
blocked, blurred, or distorted.
How
can I take care of myself?
Follow
your doctor's recommendations and these guidelines:
What
can be done to help prevent diabetic retinopathy?
To
help prevent diabetic retinopathy, follow these guidelines:
Follow
your diet and health care plan for your diabetes so you have fewer complications.
Eye
Medicines: Eyedrops and Ointments
If
you need to use eyedrops or ointments in your eyes, you will get the
most benefit from your medicine if you use it properly.
Some
general guidelines are:
-
Always
use the amount of medicine your health care provider has prescribed.
Do not use it more often than prescribed.
-
Do
not use this medicine for other eye conditions unless your health
care provider approves.
- Never
share eye medicines with others.
- Before
you start, wash your hands thoroughly.
- Read
the label on the medicine to make sure you have the right one.
If
you develop any new redness or irritation while you are using your
medicine, contact your health care provider.
How
are eyedrops used?
If
you have trouble using eyedrops, ask someone to help.
How
are eye ointments used?
-
Hold
the tube of ointment in your hand for a few moments. This will warm
the medicine so it will flow easily from the tube. Do not use
ointment that has dried out.
-
Tilt
your head back, and pull your lower eyelid down to form a pouch.
- Look
up, and squeeze a 1/4-inch-long ribbon of ointment into the pouch.
To avoid contaminating the medicine, do not let the tip of the tube
touch your eye or any other surface.
- Blink
a few times to help spread the ointment over your eye. Do not rub
your eye.
- Put
the cap on tightly, and store the medicine away from heat and bright light.
Your
vision may be blurry for some time after using your ointment. Avoid
driving and other activities that require good vision until you can
see clearly.
Can
I wear contact lenses while I am using eye medicines?
Do
not wear your contacts when you are putting eye medicines in your
eyes. Sometimes you can put your contacts in about 10 minutes after
you have used your medicine. However, some eye medicines will stain
your contacts. Ask your health care provider about wearing contacts
while you are using your eye medicine.
If
you have any questions about using your eye medicines properly, ask
your health care provider.
Chemical
in Eye
DESCRIPTION
Acids
and alkalis splashed into the eye can severely damage the cornea
(clear part of the eye). However, most chemicals just cause temporary
stinging and superficial irritation (for example, alcohol or
hydrocarbons). All should be treated as emergencies and preferably by
an eye doctor.
FIRST
AID
Immediate
and thorough irrigation of the eye with tap water is essential to
prevent damage to the cornea. (Do not use antidotes such as vinegar.)
This irrigation should be performed at home and as quickly as
possible. Either hold your child's face up under a gently running
water tap or have your child lie down and continuously pour lukewarm
water into the eye from a glass. It is very important to hold the
eyelids open during this process. For most chemicals, the eye should
be irrigated for 5 minutes. However, it should be irrigated for 10
minutes for acids and 20 minutes for alkalis. Immediately consult an
eye doctor for further advise.
Eye
Trauma
DESCRIPTION
This
guideline covers injuries to the eye, eyelid, and area around the
eye. The main concern is possible damage to your child's vision.
Older children can tell us if their vision is blurred or out of
focus. Test your child's vision at home by covering each eye in turn
and having your child look at a distant object. Children less than 3
years old usually need to be examined by a physician to answer this question.
HOME
CARE
Superficial
cuts or scrapes
First
wash your hands. Protect the eye with a clean cloth, then wash the
wound vigorously with liquid soap and water for 5 minutes. Rinse the
wound well. Then apply pressure for 10 minutes with a sterile gauze
to stop bleeding. Leave the area exposed to the air. Antiseptic
ointments are usually unnecessary.
Swelling
or bruises with intact skin
Swelling
usually follows injury to the soft tissues or bone around the eye.
Apply ice for 20 minutes. A subconjunctival hemorrhage (bruise of the
white of the eyeball) also shouldn't cause undue concern. These
unsightly bruises are harmless. They do not spread to inside the eye
and clear up in about 2 weeks.
Prevention
of eye trauma
o
Objects that penetrate the eyeball often result in loss of vision.
Don't buy your child an air-powered gun (BB gun).
CALL
YOUR CHILD'S PHYSICIAN IMMEDIATELY IF:
Foreign
Body in Eye
DESCRIPTION
An
eyelash, sawdust, sand, or dirt can get into the eyes. The main
symptom is irritation or pain.
FIRST
AID FOR GLASS FRAGMENTS ON THE EYELIDS
With
your child bending forward, try to get flakes of glass off the skin
by blowing on the closed eyelids. Pour water over the eyelids and
face to get off any remaining glass. Cover the eyes with a wet
washcloth and consult an eye doctor. The eye should not be rubbed.
HOME
CARE
If
there are numerous particles in the eye (such as dirt or sand),
clean around the eye with a wet washcloth first. Then have your child
try to open and close the eye repeatedly while submerging that side
of the face in a pan of water. If your child is too young to
cooperate with this, hold him face up under a gently running warm
water tap. The eyelids must be held open during the irrigation.
If
the particle is in the corner of the eye, try to get it out with the
corner of a clean handkerchief or a moistened cotton swab.
If
the particle is under the lower eyelid, pull the lower lid out by
depressing the cheek and touch the particle with a moistened cotton
swab. If that doesn't work, try pouring water on the speck while
holding the lid out.
If
the particle can't be seen, it's probably under the upper lid (the
most common hiding place). Try having your child open and close the
eye several times while his face is submerged in a cake pan or pie
pan of water. If this fails, pull the upper lid out and draw it over
the lower lid. This will sometimes dislodge the particle.
CALL
YOUR CHILD'S PHYSICIAN IMMEDIATELY IF:
-
The
object hit the eye at high speed (as from striking metal on metal or
metal on stone).
-
The
foreign object is sharp.
-
Irrigation
does not remove all the foreign material from the eye (that is, you
can see it or the sensation of "grittiness" or pain persists).
(While
your child is waiting to be seen by the physician, cover his eye
with a wet washcloth or bandage it shut to relieve discomfort.)
-
Your
child's vision does not return to normal after the eye has been irrigated.
-
The
foreign object has been removed, but tearing and blinking persist.
Glaucoma
What
is glaucoma?
Glaucoma
is an eye disease in which the optic nerve is damaged. Usually, high
pressure inside the eye causes the damage. The damage can lead to a
loss of vision. However, early treatment can prevent blindness.
How
does it occur?
A
clear, watery fluid called the aqueous humor normally circulates in
your eye. When the flow of this fluid out of the eye becomes blocked,
the pressure increases inside the eye. The increased pressure can
damage the optic nerve.
There
are two main types of glaucoma, depending on how the flow of fluid
is blocked:
-
Open-angle
glaucoma is caused by a gradual blockage in the area that drains
fluid from the eyes into the drainage channels. It usually affects
both eyes.
-
Closed-angle
glaucoma is a blockage caused by a change in the position of the
iris (the colored part of the eye). The change in position causes the
iris to block the drainage channels. This type of glaucoma usually
happens in one eye at a time. If you get glaucoma in one eye, you are
at risk for having the same problem in the other eye. When this type
of glaucoma happens suddenly, it is called acute closed-angle
glaucoma and is a medical emergency.
-
Glaucoma
tends to run in families. It occurs most often after age 40, but
sometimes children have it.
What
are the symptoms?
Open-angle
and other chronic forms of glaucoma often have no symptoms in the
early stages. In later stages, you will begin to notice a loss of
vision. Side vision is affected first.
Symptoms
of acute closed-angle glaucoma include:
How
is it diagnosed?
Your
health care provider may screen you for vision problems during your
routine checkups. If you have vision problems, your provider will
refer you to an eye doctor.
The
eye doctor may use the following tests to diagnose glaucoma:
-
Tonometry,
a painless procedure used to measure the pressure in your eyes
-
Ophthalmoscopy,
in which the doctor uses an instrument to look at the optic nerve
inside your eye
- Visual
field testing, which can show early changes in your side vision
caused by damage to the optic nerve
- Gonioscopy,
which is a method of examining the drainage channels.
How
is it treated?
The
goal in the treatment of glaucoma is to reduce the pressure in your
eyes. This may be done with eye drops, oral medication, laser
surgery, or other types of surgery. Some eye drops reduce the amount
of fluid made by your eye. Others increase the amount of fluid that
flows out. Surgery relieves pressure inside the eye by opening up the
drainage channel or by making another opening through which the fluid
can drain.
How
long will the effects last?
Loss
of vision caused by glaucoma is permanent. This is why glaucoma
needs to be diagnosed and treated early to stop further damage to the
optic nerve.
If
your eye doctor prescribes medication to control the pressure, you
may need to take it for the rest of your life.
How
can I take care of myself?
How
can I help prevent glaucoma?
Glaucoma
cannot be prevented. However, blindness can be prevented if glaucoma
is treated before pressure in the eye has damaged the optic nerve too much.
You
may be able to help prevent glaucoma from becoming severe if you:
-
Have
a regular eye exam. How often you need to see the eye doctor will
depend on how severely your optic nerve was damaged.
-
At
your eye exam, make sure the pressure in your eye is measured and
that your optic nerve is examined.
- Learn
about your family history. Chronic open-angle glaucoma often runs in families.
- See
your health care provider at once if you see halos around lights or
notice any changes in your vision.
Headaches
and Eye Problems
Do
eye problems cause headaches?
Headaches
are a very common health problem. They can have many different
causes. Sometimes, but not usually, eye problems are a cause.
What
causes headaches?
Tension,
anxiety, strain, stress, fatigue, and depression may all bring about
sudden or gradual muscle contraction and pain.
Migraine
headaches are another common type of headache. Migraines are usually
much more severe than muscle contraction headaches. They are caused
by changes in the blood vessels and blood flow in the head.
Headaches
can also be caused by many diseases and disorders affecting other
parts of the body. For example, ear problems, jaw problems, sinus
problems, arthritis, high blood pressure, nerve diseases, and even
tumors can cause headaches.
Rarely,
eye problems cause headaches. For example, if you need reading
glasses and read for a long time without glasses, or with glasses
that are too weak, you may develop eye strain and a headache. Also,
you may have a headache from reading or doing close work if your eyes
are misaligned. That is, certain eye muscles may be too weak to focus
up close. This weakness is one of the few eye problems that can often
be successfully treated with eye muscle exercises.
How
are headaches treated?
Treatment
for headaches varies, depending on the cause. Proper diagnosis is
important, so tell your health care provider if you have severe,
frequent, or ongoing headaches. He or she will try to determine the
cause and proper treatment.
If
it appears that your headaches are caused by eye problems, you may
be referred to an eye doctor. A new glasses prescription may be the
treatment you need. If your eyes are misaligned, eye muscle exercises
are often helpful.
How
can I help prevent headaches caused by eye problems?
Make
sure you have regular checkups with your eye doctor
Presbyopia
What
is presbyopia?
Presbyopia
is the loss of clear close-up vision that occurs naturally as people
get older.
How
does it occur?
Around
the age of 40, the lenses of your eyes begin to lose elasticity and
flexibility. You may find that you are unable to focus sharply on
close objects. You may need to hold things farther away from your
eyes to see them clearly.
What
are the symptoms?
Presbyopia
develops gradually. At first you may have blurred vision when you
read or do close-up tasks such as threading a needle. Later you may
not be able to read normal newsprint or book print without reading
glasses or a magnifying glass and good lighting.
How
is it diagnosed?
Presbyopia
does not require diagnosis if you have no other symptoms. Your eye
doctor can verify your condition during a regular visit or glaucoma check.
How
is it treated?
There
is no treatment that can make your lenses flexible again. However,
reading glasses, bifocals, trifocals, progressive lenses (no lines),
and possibly contact lenses can help you see close-up objects.
Discuss these options with your eye doctor.
How
long will the effects last?
Presbyopia
is a permanent change that tends to worsen very gradually over time.