 |
Cataracts Guide - what you should know
What is a cataract?
A cataract is a clouding of the
lens in the eye that
affects
vision. Most cataracts are related to aging.
Cataracts are very common in older people. By age
80, more than half of all Americans either have a
cataract or have had cataract surgery.
A cataract can occur in either or both eyes. It
cannot spread from one eye to the other.
Cataract
In a normal eye, light passes through
the transparent
lens to the
retina. Once it
reaches the retina, light is changed into
nerve signals that are sent to the brain.
The lens must be clear for the retina to
receive a sharp image. If the lens is cloudy
from a cataract, the image you see will be
blurred.
QuickClip Anatomy Movie
Illustration and movie by
JirehDesign.com |
 |
What is the lens?
The lens is a clear part of the eye that helps to
focus light, or an image, on the
retina. The retina
is the light-sensitive tissue at the back of the
eye.
How do cataracts develop?
Age-related cataracts develop in two ways:
- Clumps of protein reduce the sharpness of
the image reaching the retina.
The lens consists mostly of water and protein.
When the protein clumps up, it clouds the lens
and reduces the light that reaches the retina.
The clouding may become severe enough to cause
blurred vision. Most age-related cataracts
develop from protein clumpings.
When a cataract is small, the cloudiness affects
only a small part of the lens. You may not
notice any changes in your vision. Cataracts
tend to "grow" slowly, so vision gets worse
gradually. Over time, the cloudy area in the
lens may get larger, and the cataract may
increase in size. Seeing may become more
difficult. Your vision may get duller or
blurrier.
- The clear lens slowly changes to a
yellowish/brownish color, adding a brownish tint
to vision.
As the clear lens slowly colors with age, your
vision gradually may acquire a brownish shade.
At first, the amount of tinting may be small and
may not cause a vision problem. Over time,
increased tinting may make it more difficult to
read and perform other routine activities. This
gradual change in the amount of tinting does not
affect the sharpness of the image transmitted to
the retina.
If you have advanced lens discoloration, you may
not be able to identify blues and purples. You
may be wearing what you believe to be a pair of
black socks, only to find out from friends that
you are wearing purple socks.
Who is at risk for cataract?
The risk of cataract increases as you get older.
Other risk factors for cataract include:
- Certain diseases (for example,
diabetes).
- Personal behavior (smoking, alcohol
use).
- The environment (prolonged exposure to
ultraviolet sunlight).
What are the symptoms of a cataract?
The most common symptoms of a cataract are:
- Cloudy or blurry vision.
- Colors seem faded.
- Glare. Headlights, lamps, or
sunlight may appear too bright. A halo
may appear around lights.
- Poor night vision.
- Double vision or multiple images in
one eye. (This symptom may clear as the
cataract gets larger.)
- Frequent prescription changes in
your eyeglasses or contact lenses.
These symptoms also can be a sign of
other eye problems. If you have any of
these symptoms, check with your eye care
professional.
Are there other types of cataract?
Yes. Although most cataracts are related
to aging, there are other types of
cataract:
- Secondary cataract. Cataracts
can form after surgery for other eye
problems, such as
glaucoma.
Cataracts also can develop in people
who have other health problems, such
as diabetes. Cataracts are sometimes
linked to steroid use.
- Traumatic cataract. Cataracts
can develop after an eye injury,
sometimes years later.
- Congenital cataract. Some babies
are born with cataracts or develop
them in childhood, often in both
eyes. These cataracts may be so
small that they do not affect
vision. If they do, the lenses may
need to be removed.
- Radiation cataract. Cataracts
can develop after exposure to some
types of radiation.
Normal vision |
The same seen as viewed
by a person with a
cataract |
How is a cataract detected?
Cataract is detected through a
comprehensive eye exam that
includes:
Visual acuity test. This
eye chart test measures how well you
see at various distances.
-
Dilated eye exam
Drops are placed in your
eyes to widen, or dilate, the
pupils. Your eye care
professional uses a special
magnifying lens to examine your
retina and
optic nerve for signs
of damage and other eye
problems. After the exam, your
close-up vision may remain
blurred for several hours.
- Tonometry
An instrument measures the
pressure inside the eye. Numbing
drops may be applied to your eye
for this test.
Your eye care professional also
may do other tests to learn more
about the structure and health
of your eye.
How is a cataract treated?
The symptoms of early cataract
may be improved with new
eyeglasses, brighter lighting,
anti-glare sunglasses, or
magnifying lenses. If these
measures do not help, surgery is
the only effective treatment.
Surgery involves removing the
cloudy
lens and replacing it
with an artificial lens.
A cataract needs to be removed
only when vision loss interferes
with your everyday activities,
such as driving, reading, or
watching TV. You and your eye
care professional can make this
decision together. Once you
understand the benefits and
risks of surgery, you can make
an informed decision about
whether cataract surgery is
right for you. In most cases,
delaying cataract surgery will
not cause long-term damage to
your eye or make the surgery
more difficult. You do not have
to rush into surgery.
Sometimes a cataract should be
removed even if it does not
cause problems with your vision.
For example, a cataract should
be removed if it prevents
examination or treatment of
another eye problem, such as
age-related macular degeneration
or
diabetic retinopathy.
If you choose surgery, your eye
care professional may refer you
to a specialist to remove the
cataract.
If you have cataracts in both
eyes that require surgery, the
surgery will be performed on
each eye at separate times,
usually four to eight weeks
apart.
Is cataract surgery
effective?
Cataract removal is one of the
most common operations performed
in the United States. It also is
one of the safest and most
effective types of surgery. In
about 90 percent of cases,
people who have cataract surgery
have better vision afterward.
Are there different types of
cataract surgery?
There are two types of cataract
surgery. Your doctor can explain
the differences and help
determine which is better for
you:
-
Phacoemulsification,
or phaco
A small incision is made on
the side of the
cornea, the
clear, dome-shaped surface
that covers the front of the
eye. Your doctor inserts a
tiny probe into the eye.
This device emits ultrasound
waves that soften and break
up the
lens so that it can
be removed by suction. Most
cataract surgery today is
done by phacoemulsification,
also called "small incision
cataract surgery."
- Extracapsular surgery
Your doctor makes a longer
incision on the side of the
cornea and removes the
cloudy core of the lens in
one piece. The rest of the
lens is removed by suction.
After the natural lens has
been removed, it often is
replaced by an artificial
lens, called an intraocular
lens (IOL). An IOL is a
clear, plastic lens that
requires no care and becomes
a permanent part of your
eye. Light is focused
clearly by the IOL onto the
retina, improving your
vision. You will not feel or
see the new lens.
Some people cannot have an
IOL. They may have another
eye disease or have problems
during surgery. For these
patients, a soft contact
lens, or glasses that
provide high magnification,
may be suggested.
What are the risks of
cataract surgery?
As with any surgery,
cataract surgery poses
risks, such as infection and
bleeding. Before cataract
surgery, your doctor may ask
you to temporarily stop
taking certain medications
that increase the risk of
bleeding during surgery.
After surgery, you must keep
your eye clean, wash your
hands before touching your
eye, and use the prescribed
medications to help minimize
the risk of infection.
Serious infection can result
in loss of vision.
Cataract surgery slightly
increases your risk of
retinal detachment. Other
eye disorders, such as high
myopia (nearsightedness),
can further increase your
risk of retinal detachment
after cataract surgery. One
sign of a retinal detachment
is a sudden increase in
flashes or floaters.
Floaters are little
"cobwebs" or specks that
seem to float about in your
field of vision. If you
notice a sudden increase in
floaters or flashes, see an
eye care professional
immediately. A retinal
detachment is a medical
emergency. If necessary, go
to an emergency service or
hospital. Your eye must be
examined by an eye surgeon
as soon as possible. A
retinal detachment causes no
pain. Early treatment for
retinal detachment often can
prevent permanent loss of
vision. The longer the
retina stays detached, the
less likely you will regain
good vision once you are
treated. Even if you are
treated promptly, some
vision may be lost.
Talk to your eye care
professional about these
risks. Make sure cataract
surgery is right for you.
What if I have other eye
conditions and need cataract
surgery?
Many people who need
cataract surgery also have
other eye conditions, such
as age-related
macular
degeneration or glaucoma. If
you have other eye
conditions in addition to
cataract, talk with your
doctor. Learn about the
risks, benefits,
alternatives, and expected
results of cataract surgery.
What happens before
surgery?
A week or two before
surgery, your doctor will do
some tests. These tests may
include measuring the curve
of the
cornea and the size
and shape of your eye. This
information helps your
doctor choose the right type
of IOL.
You may be asked not to eat
or drink anything 12 hours
before your surgery.
What happens during
surgery?
At the hospital or eye
clinic, drops will be put
into your eye to dilate the
pupil. The area around your
eye will be washed and
cleansed.
The operation usually lasts
less than one hour and is
almost painless. Many people
choose to stay awake during
surgery. Others may need to
be put to sleep for a short
time. If you are awake, you
will have an anesthetic to
numb the nerves in and
around your eye.
After the operation, a patch
may be placed over your eye.
You will rest for a while.
Your medical team will watch
for any problems, such as
bleeding. Most people who
have cataract surgery can go
home the same day. You will
need someone to drive you
home.
What happens after
surgery?
Itching and mild discomfort
are normal after cataract
surgery. Some fluid
discharge is also common.
Your eye may be sensitive to
light and touch. If you have
discomfort, your doctor can
suggest treatment. After one
or two days, moderate
discomfort should disappear.
More about cataract and
refractive surgery.
For a few days after
surgery, your doctor may ask
you to use eyedrops to help
healing and decrease the
risk of infection. Ask your
doctor about how to use your
eyedrops, how often to use
them, and what effects they
can have. You will need to
wear an eye shield or
eyeglasses to help protect
your eye. Avoid rubbing or
pressing on your eye.
When you are home, try not
to bend from the waist to
pick up objects on the
floor. Do not lift any heavy
objects. You can walk, climb
stairs, and do light
household chores.
In most cases, healing will
be complete within eight
weeks. Your doctor will
schedule exams to check on
your progress.
Can problems develop
after surgery?
Problems after surgery are
rare, but they can occur.
These problems can include
infection, bleeding,
inflammation (pain, redness,
swelling), loss of vision,
double vision, and high or
low eye
pressure. With
prompt medical attention,
these problems usually can
be treated successfully.
Sometimes the eye tissue
that encloses the IOL
becomes cloudy and may blur
your vision. This condition
is called an after-cataract.
An after-cataract can
develop months or years
after cataract surgery.
An after-cataract is treated
with a laser. Your doctor
uses a laser to make a tiny
hole in the eye tissue
behind the lens to let light
pass through. This
outpatient procedure is
called a YAG laser
capsulotomy. It is painless
and rarely results in
increased eye pressure or
other eye problems. As a
precaution, your doctor may
give you eyedrops to lower
your eye pressure before or
after the procedure.
More about cataract and
refractive surgery.
When will my vision be
normal again?
You can return quickly to
many everyday activities,
but your
vision may be
blurry. The healing eye
needs time to adjust so that
it can focus properly with
the other eye, especially if
the other eye has a
cataract. Ask your doctor
when you can resume driving.
If you received an IOL, you
may notice that colors are
very bright. The IOL is
clear, unlike your
natural
lens that may have had a
yellowish/brownish tint.
Within a few months after
receiving an IOL, you will
become used to improved
color vision. Also, when
your eye heals, you may need
new glasses or contact
lenses.
What can I do if I
already have lost some
vision from cataract?
If you have lost some sight
from cataract or cataract
surgery, ask your eye care
professional about
low
vision services and devices
that may help you make the
most of your remaining
vision. Ask for a referral
to a specialist in
low
vision. Many community
organizations and agencies
offer information about low
vision counseling, training,
and other special services
for people with visual
impairments. A nearby school
of medicine or optometry may
provide low vision services.
What research is being
done?
The National Eye Institute
is conducting and supporting
a number of studies focusing
on factors associated with
the development of
age-related cataract. These
studies include:
- The effect of
sunlight exposure, which
may be associated with
an increased risk of
cataract.
- Vitamin supplements,
which have shown varying
results in delaying the
progression of cataract.
- Genetic studies,
which show promise for
better understanding
cataract development.
What can I do to
protect my vision?
Wearing sunglasses and a
hat with a brim to block
ultraviolet sunlight may
help to delay cataract.
If you smoke, stop.
Researchers also believe
good nutrition can help
reduce the risk of
age-related cataract.
They recommend eating
green leafy vegetables,
fruit, and other foods
with antioxidants.
If you are age 60 or
older, you should have a
comprehensive
dilated
eye exam at least once
every two years. In
addition to cataract,
your eye care
professional can check
for signs of
age-related
macular degeneration,
glaucoma, and other
vision disorders. Early
treatment for many eye
diseases may save your
sight.
What should I ask my
eye care professional?
You can protect yourself
against vision loss by
working in partnership
with your eye care
professional. Ask
questions and get the
information you need to
take care of yourself
and your family.
What are some
questions to ask?
About my eye
disease or disorder…
- What is my
diagnosis?
- What caused
my condition?
- Can my
condition be
treated?
- How will
this condition
affect my vision
now and in the
future?
- Should I
watch for any
particular
symptoms and
notify you if
they occur?
- Should I
make any
lifestyle
changes?
About my
treatment…
- What is
the
treatment
for my
condition?
- When
will the
treatment
start and
how long
will it
last?
- What are
the benefits
of this
treatment
and how
successful
is it?
- What are
the risks
and side
effects
associated
with this
treatment?
- Are
there foods,
drugs, or
activities I
should avoid
while I'm on
this
treatment?
- If my
treatment
includes
taking
medicine,
what should
I do if I
miss a dose?
- Are
other
treatments
available?
About my
tests…
- What
kinds of
tests
will I
have?
- What
can I
expect
to find
out from
these
tests?
- When
will I
know the
results?
- Do I
have to
do
anything
special
to
prepare
for any
of the
tests?
- Do
these
tests
have any
side
effects
or
risks?
- Will
I need
more
tests
later?
Other
suggestions
-
If
you
don't
understand
your
eye
care
professional's
responses,
ask
questions
until
you
do
understand.
-
Take
notes
or
get
a
friend
or
family
member
to
take
notes
for
you.
Or,
bring
a
tape
recorder
to
help
you
remember
the
discussion.
-
Ask
your
eye
care
professional
to
write
down
his
or
her
instructions
to
you.
-
Ask
your
eye
care
professional
for
printed
material
about
your
condition.
-
If
you
still
have
trouble
understanding
your
eye
care
professional's
answers,
ask
where
you
can
go
for
more
information.
-
Other
members
of
your
health
care
team,
such
as
nurses
and
pharmacists,
can
be
good
sources
of
information.
Talk
to
them,
too.
Today,
patients
take
an
active
role
in
their
health
care.
Be
an
active
patient
about
your
eye
care.
Where
can
I
get
more
information?
For
more
information
about
cataract,
you
may
wish
to
contact:
EyeSurgeryChoices.com
American
Academy
of
Ophthalmology*
P.O.
Box
7424
San
Francisco,
CA
94120-7424
415-561-8500
www.aao.org
American
Optometric
Association*
243
North
Lindbergh
Boulevard
St.
Louis,
MO
63141-7851
314-991-4100
www.aoa.org
National
Eye
Institute*
National
Institutes
of
Health
2020
Vision
Place
Bethesda,
MD
20892-3655
301-496-5248
E-mail:
2020@nei.nih.gov
www.nei.nih.gov
Prevent
Blindness
America
500
East
Remington
Road
Schaumburg,
IL
60173-4557
1-800-331-2020
847-843-2020
E-mail:
info@preventblindness.org
www.preventblindness.org
For
more
information
about
IOLs,
contact:
U.S.
Food
and
Drug
Administration
Office
of
Consumer
Affairs
Parklawn
Building
(HFE-88)
5600
Fishers
Lane
Rockville,
MD
20857
1-888-463-6332
www.fda.gov
For
more
information
about
low
vision
services
and
programs,
you
may
wish
to
contact:
American
Foundation
for
the
Blind
11
Penn
Plaza,
Suite
300
New
York,
NY
10011-2006
1-800-232-5463
212-502-7600
E-mail:
afbinfo@afb.net
www.afb.org
Council
of
Citizens
with
Low
Vision
International
1-800-733-2258
Lighthouse
International
111
East
59th
Street
New
York,
NY
10022-1202
1-800-334-5497
1-800-829-0500
212-821-9200
212-821-9713
(TDD)
E-mail:
info@lighthouse.org
www.lighthouse.org
National
Association
for
Visually
Handicapped
22
West
21st
Street,
6th
Floor
New
York,
NY
10010-6943
212-889-3141
www.navh.org
*
These
organizations
also
provide
information
on
low
vision.
Courtesy
of
the
National
Eye
Institute
More
about
cataract
and
refractive
surgery |
|
