Cataract
A
cataract is a clouding of the normally clear lens of your eye. For people who
have cataracts, seeing through cloudy lenses is a bit like looking through a
frosty or fogged-up window.
Clouded
vision caused by cataracts can make it more difficult to read, drive a car
(especially at night) or see the expression on a friend's face.
Most
cataracts develop slowly and don't disturb your eyesight early on. But with
time, cataracts will eventually interfere with your vision.
At first,
stronger lighting and eyeglasses can help you deal with cataracts. But if
impaired vision interferes with your usual activities, you might need cataract
surgery. Fortunately, cataract surgery is generally a safe, effective
procedure.
Symptoms
Signs
and symptoms of cataracts include:
·
Clouded, blurred or dim vision
·
Increasing difficulty with
vision at night
·
Sensitivity to light and glare
·
Seeing "halos" around
lights
·
Frequent changes in eyeglass
or contact lens prescription
·
Fading or yellowing of colors
·
Double vision in a single eye
At
first, the cloudiness in your vision caused by a cataract may affect only a
small part of the eye's lens and you may be unaware of any vision loss. As the
cataract grows larger, it clouds more of your lens and distorts the light
passing through the lens. This may lead to signs and symptoms you're more
likely to notice.
When to see a
doctor
Make an
appointment for an eye exam if you notice any changes in your vision. If you
develop sudden vision changes, such as double vision or blurriness, see your
doctor right away.
Causes
Most
cataracts develop when aging or injury changes the tissue that makes up your
eye's lens.
Some
cataracts are related to inherited genetic disorders that cause other health
problems and increase your risk of cataracts. Cataracts can also be caused by other
eye conditions, medical conditions such as diabetes, trauma or past eye
surgery. Long-term use of steroid medications, too, can cause cataracts to
develop.
How a cataract
forms
The
lens, where cataracts form, is positioned behind the colored part of your eye
(iris). The lens focuses light that passes into your eye, producing clear,
sharp images on the retina — the light-sensitive membrane on the back inside
wall of your eyeball that functions like the film of a camera.
A
cataract scatters the light as it passes through the lens, preventing a sharply
defined image from reaching your retina. As a result, your vision becomes
blurred.
As
you age, the lenses in your eyes become less flexible, less transparent and
thicker. Age-related changes cause tissues within the lens to break down and
clump together, clouding small areas within the lens. As the cataract continues
to develop, the clouding becomes denser and involves a greater part of the
lens.
Cataracts
may develop in only one eye, but they usually develop in both of your eyes.
However, the cataracts usually aren't totally symmetrical, and the cataract in
one eye may be more advanced than the other.
Types of
cataracts
Cataract
types include:
·
Cataracts that
affect the center of the lens (nuclear cataracts).
A nuclear cataract may at first cause you to become more nearsighted or even
experience a temporary improvement in your reading vision. But with time, the
lens gradually turns more densely yellow and further clouds your vision.
As the cataract
slowly progresses, the lens may even turn brown. Advanced yellowing or browning
of the lens can lead to difficulty distinguishing between shades of color.
·
Cataracts that
affect the edges of the lens (cortical cataracts).
A cortical cataract begins as whitish, wedge-shaped opacities or streaks on the
outer edge of the lens cortex.
As it slowly
progresses, the streaks extend to the center and interfere with light passing
through the center of the lens. People with cortical cataracts often experience
problems with glare.
·
Cataracts that
affect the back of the lens (posterior subcapsular cataracts).
A posterior subcapsular cataract starts as a small, opaque area that usually
forms near the back of the lens, right in the path of light on its way to the
retina.
A posterior
subcapsular cataract often interferes with your reading vision, reduces your
vision in bright light, and causes glare or halos around lights at night.
·
Cataracts you're
born with (congenital cataracts). Some people are
born with cataracts or develop them during childhood. Such cataracts may be the
result of the mother having contracted an infection during pregnancy.
These
cataracts also may be due to certain conditions, such as myotonic dystrophy,
galactosemia, Lowe's syndrome or rubella. Congenital cataracts don't always
affect vision, but if they do they're usually removed soon after detection.
Risk
factors
Factors
that increase your risk of cataracts include:
·
Increasing age
·
Diabetes
·
Drinking excessive amounts of
alcohol
·
Excessive exposure to sunlight
·
Exposure to ionizing
radiation, such as that used in X-rays and cancer radiation therapy
·
Family history of cataracts
·
High blood pressure
·
Obesity
·
Previous eye injury or
inflammation
·
Previous eye surgery
·
Prolonged use of
corticosteroid medications
·
Smoking
Preparing
for your appointment
Make
an appointment with your usual eye care provider if you notice changes in your
vision. If your doctor determines that you have cataracts, then you may be
referred to an eye specialist who can perform cataract surgery
(ophthalmologist).
Because
appointments can be brief, and because there's often a lot to talk about, it's
a good idea to be well prepared for your appointment. Here's some information
to help you get ready and know what to expect from your doctor.
What you can do
·
Write
down any symptoms you're experiencing,
including any that may seem unrelated to the reason for which you scheduled the
appointment.
·
Write
down key personal information, including any
major stresses or recent life changes.
·
Make
a list of all medications, vitamins or
supplements that you're taking.
·
Take
a family member or friend along. Sometimes it
can be difficult to absorb all the information provided during an appointment.
Someone who accompanies you may remember something that you missed or forgot.
·
Write
down questions to ask your doctor.
Your
time with your doctor is limited, so preparing a list of questions will help
you make the most of your time together. List your questions from most
important to least important in case time runs out. For cataracts, some basic
questions to ask include:
·
Are cataracts causing my
vision problems?
·
What are other possible causes
for my vision problems?
·
What kinds of tests do I need?
·
Do I need cataract surgery?
·
Will cataract surgery correct
my vision problems?
·
What are the potential risks
of cataract surgery?
·
What will cataract surgery
cost, and will my insurance cover it?
·
Can I drive myself home after
cataract surgery?
·
How much time will I need to
recover from cataract surgery?
·
Will any usual activities be
restricted after cataract surgery? For how long?
·
After cataract surgery, how
long should I wait before getting new glasses?
·
If I use Medicare, will it
cover the cost of cataract surgery? Does Medicare cover the cost of new glasses
after surgery?
·
How long can I take to decide
about cataract surgery?
·
Are there risks to delaying
cataract surgery?
·
If I wait a year or more
before having surgery, will this make it more likely that surgery won't restore
my vision?
·
If I don't want surgery right
now, what else can I do to cope with my vision changes?
·
How will I know if my
cataracts are getting worse?
·
I have these other health
conditions. How can I best manage them together?
·
Are there any restrictions
that I need to follow?
·
Are there any brochures or
other printed material that I can take with me? What websites do you recommend?
·
What will determine whether I
should plan for a follow-up visit?
In
addition to the questions that you've prepared to ask your doctor, don't hesitate
to ask questions at any time that you don't understand something.
What to expect
from your doctor
Your
doctor is likely to ask you a number of questions. Being ready to answer them
may allow more time later to cover other points you want to address. Your
doctor may ask:
·
When did you begin
experiencing symptoms?
·
Have your symptoms been
continuous or occasional?
·
Do you experience vision
problems in bright light?
·
How severe are your symptoms?
·
Do your vision problems make
it difficult for you to drive?
·
Do your vision problems make
it difficult to read?
·
Do your vision problems make
it difficult to do your job?
·
Have you ever had eye surgery?
·
Have you ever had an eye
injury?
·
Have you ever been diagnosed
with an eye problem, such as inflammation of your iris (iritis)?
·
Have you ever received
radiation therapy to your head or neck?
·
What medications are you
currently taking?
Tests
and diagnosis
To
determine whether you have a cataract, your doctor will review your medical
history and symptoms, and perform an eye examination. Your doctor may conduct
several tests, including:
·
Asking you to
read an eye chart (visual acuity test).
A visual acuity test uses an eye chart to measure how well you can read a
series of letters. Your eyes are tested one at a time, while the other eye is
covered.
Using a chart or
a viewing device with progressively smaller letters, your eye doctor determines
if you have 20/20 vision or if your vision shows signs of impairment.
·
Using a light
and magnification to examine your eye (slit-lamp examination).
A slit lamp allows your eye doctor to see the structures at the front of your
eye under magnification.
The microscope
is called a slit lamp because it uses an intense line of light, a slit, to
illuminate your cornea, iris, lens, and the space between your iris and cornea.
The slit allows your doctor to view these structures in small sections, which
makes it easier to detect any tiny abnormalities.
·
Dilating your
eyes (retinal examination). To prepare for
a retinal examination, your eye doctor puts dilating drops in your eyes to open
your pupils wide. This makes it easier to examine the back of your eyes
(retina).
Using
a slit lamp or a special device called an ophthalmoscope, your eye doctor can
examine your lens for signs of a cataract
Treatments
and drugs
The
only effective treatment for cataracts is surgery.
When to consider
cataract surgery
Talk
with your eye doctor about whether surgery is right for you. Most eye doctors
suggest considering cataract surgery when your cataracts begin to affect your
quality of life or interfere with your ability to perform normal daily
activities, such as reading or driving at night.
It's
up to you and your doctor to decide when cataract surgery is right for you. For
most people, there is no rush to remove cataracts because they usually don't
harm the eye.
Delaying
the procedure won't make it more likely that you won't recover your vision if
you later decide to have cataract surgery. Take time to consider the benefits
and risks of cataract surgery with your doctor.
If
you choose not to undergo cataract surgery now, your eye doctor may recommend
periodic follow-up exams to see if your cataracts are progressing. How often
you'll see your eye doctor depends on your situation.
What happens
during cataract surgery
Cataract
surgery involves removing the clouded lens and replacing it with a clear
artificial lens. The artificial lens, called an intraocular lens, is positioned
in the same place as your natural lens, and it remains a permanent part of your
eye.
For
some people, other eye problems prohibit the use of an artificial lens. In these
situations, once the cataract is removed, vision may be corrected with
eyeglasses or contact lenses.
Cataract
surgery is generally done on an outpatient basis, which means you won't need to
stay in a hospital after the surgery.
During
cataract surgery, your eye doctor uses local anesthesia to numb the area around
your eye, but you usually stay awake during the procedure.
Cataract
surgery is generally safe, but it carries a risk of infection and bleeding.
Cataract surgery increases the risk of retinal detachment.
After
the procedure, you'll have some discomfort for a few days. You generally will
be healed within eight weeks.
If you need
cataract surgery in both eyes, your doctor will schedule surgery to remove the
cataract in the second eye a month or two after the first surgery.
Lifestyle
and home remedies
To
deal with symptoms of cataracts until you decide to have surgery, try to:
·
Make sure your eyeglasses or
contact lenses are the most accurate prescription possible
·
Use a magnifying glass to read
·
Improve the lighting in your
home with more or brighter lamps
·
When you go outside during the
day, wear sunglasses or a broad-brimmed hat to reduce glare
·
Limit your night driving
Self-care
measures may help for a while, but as the cataract progresses, your vision may
deteriorate further. When vision loss starts to interfere with your everyday
activities, consider cataract surgery.
Prevention
No
studies have proved how to prevent cataracts or slow the progression of
cataracts. However, doctors think several strategies may be helpful, including:
·
Have
regular eye examinations. Eye
examinations can help detect cataracts and other eye problems at their earliest
stages. Ask your doctor how often you should have an eye examination.
·
Quit
smoking. Ask your doctor for suggestions about how to stop
smoking. Medications, counseling and other strategies are available to help
you.
·
Reduce
alcohol use. Excessive alcohol use can increase the risk of
cataracts.
·
Wear
sunglasses. Ultraviolet light from the sun may contribute to
the development of cataracts. Wear sunglasses that block ultraviolet B (UVB)
rays when you're outdoors.
·
Manage
other health problems. Follow your
treatment plan if you have diabetes or other medical conditions that can
increase your risk of cataracts.
·
Maintain
a healthy weight. If you currently have a
healthy weight, work to maintain it by exercising most days of the week. If
you're overweight or obese, work to lose weight slowly by reducing your calorie
intake and increasing the amount of exercise you get each day.
·
Choose a healthy
diet that includes plenty of fruits and vegetables.
Adding a variety of colorful fruits and vegetables to your diet ensures that
you're getting many vitamins and nutrients. Fruits and vegetables have many
antioxidants, which help maintain the health of your eyes.
Studies
haven't proved that antioxidants in pill form can prevent cataracts. However, a
large population study recently showed that a healthy diet rich in vitamins and
minerals was associated with a reduced risk of developing cataracts. Fruits and
vegetables have many proven health benefits and are a safe way to increase the
amount of minerals and vitamins in your diet.
Copied from:
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