 CATARACTS
What is a Cataract?
A cataract is a clouding of the natural lens of the eye. The
lens of the eye rests behind the iris (i.e., colored part of the eye). The lens causes
light rays to focus on the retina at the back of the eye, which in turn allows us to see.
A healthy lens is transparent, but a cataract causes the lens to become cloudy,
obstructing or hindering the passage of light. Cataracts cause blurring and dimming of
vision, as well as problems with glare. It is important to recognize that a cataract is
not a growth or a film over the eye.
Cataracts are most commonly formed as a result of changes in
the lens due to the normal aging process, although certain illnesses, chemicals, or an
injury can also cause them to develop. In general, you could say that after age 50, 50% of
people have a cataract; after age 60, 60%; after age 70, 70%; and so on.
Most cataracts progress (i.e., the clouding increases) slowly
over months to years, although certain types may advance more rapidly. Usually both
eyes develop cataracts at about the same time, but sometimes (especially in cases of
injury) only one eye might be affected. Even if both eyes have a cataract, each cataract
may develop at a different rate, causing vision to be worse in one eye.
Depending on the type and placement of the cataract, a
person could have a cataract and be unaware of it. Generally, however, if the cataract
continues to develop, a person will notice gradual changes in vision, and eventually may
be unable to see well enough to do the things they want or need to do.
Symptoms of a Cataract
Part of the successful treatment of cataracts is diagnosing
them at an early stage and treating them at the right time.
The first symptoms of cataracts may be a change in the
sharpness of vision or a dulling of colors. While reading, vision may be somewhat blurred
or dimmed. When driving, it may take more effort than before to see the road. The glare at
night may be especially difficult on the eyes. These are some of the first symptoms
and a signal you should have your eyes checked for cataracts.
- Difficulty with night driving due to glare
- Glare in bright light or sunlight
- Dim and/or yellow vision
- Trouble with near work (such as reading or needlework)
- Frequent need for change in glasses
- Decreased depth perception
- Ghost images
- Decreasing color vision; colors seem dull or lackluster
Treatment
Treatment for cataracts in the early stages generally is
glasses. As the cataracts progress, frequent changes may be required in the glasses. More
advanced cataracts may require cataract surgery to restore vision.
Having a cataract does not mean that it must immediately be
treated surgically. One must determine the extent to which the cataract interferes with
daily activities or work, and assess the need for better vision. Once glasses are no
longer adequate, clear vision can be restored by removing and replacing a cloudy lens with
a new clear artificial one.
The decision to operate will be determined by you and your eye
surgeon. You will be advised from a medical standpoint on the progress of the
cataract and the necessity of the operation.
During cataract surgery, the surgeon makes a small incision in
the sclera (white) of the eye, just outside the cornea, or on the cornea
itself. To understand how the cloudy natural lens (cataract) itself is removed,
think of it as a cloudy bag of cellophane. First, the surgeon opens the front
of the bag (capsule), and cleans out the inside of the bag. The back of the bag is left in
the eye to make the eye much stronger.
In the majority of surgeries the cataract is removed
with an instrument called a phacoemulsifier. This instrument requires tremendous surgical
skill and therefore is not used by all eye surgeons. It uses high frequency sound
waves to soften (emulsify) the cataract so it can be removed from the eye through a
needle-like instrument. This particular procedure, which is called
phacoemulsification) requires only a very tiny opening into the eye, which improves
recovery time. In most phacoemulsification instances, the incision is so small that
it seals itself, and no stitches are necessary.
Patients who have cataract surgery usually have the natural
lens replaced by an
artificial lens (intraocular lens, or IOL) at the same time. Several measurements
help determine the exact dimensions of the eye and the appropriate power of the
replacement lens.
An IOL is made of a safe, non-toxic synthetic material which
is compatible
with eye tissue and will not deteriorate over time. It is the most modern form of
lens replacement and can restore near normal vision for most cataract patients,
allowing full side-to-side vision and little or no double vision.
IOLs are implanted inside the eye during surgery in the same
location as the
natural lens, and therefore do not require removal, cleaning, or insertion. Most
intraocular lenses last a lifetime.
Cataract removal and intraocular lens implantation is
one of the safest surgeries
done on the human body. Complications rarely occur, but possible complications will be
discussed before surgery. More than 1.3 million cataract surgeries are performed every
year in the United States, with a success rate well over 90%. While it's a relatively
complex surgery for the surgery team, it's an easy, painless surgery for the patient,
lasting no more than 15 minutes.
What to Expect after Cataract
Surgery
Since most cataract surgery is done on an outpatient basis,
patients leave the surgery center within a few hours--but someone else must drive
home!
There are certain "do's" and
"don'ts" to follow after cataract surgery. Usually, a patient may continue
to perform light household duties almost immediately after surgery.
- Do be careful to avoid hitting the eye.
- Do not strain or lift anything heavy for one week.
- Do wear an eye shield at night and glasses during the day for one week to protect the
eye.
- Patients are also given eye drops to use for approximately 3-4 weeks.
Can You Prevent Cataracts?
Unfortunately, we don't fully understand what causes cataracts
to form as we age. At this time there is little we can do to prevent them. However, some
studies have shown that people who spend a lot of time in the sun tend to develop
cataracts sooner than others. Therefore, it might not hurt to wear sunglasses or a hat to
limit exposure to Ultraviolet light. Also, there is evidence that a diet high in
vegetables and fruits, and/or antioxidant vitamin supplements, may slow development.
Frequently Asked Questions
About Cataracts
What is a cataract?
What causes cataracts?
Most cataracts occur as part of the aging process. However, in some instances,
diabetes, trauma, strong family history and various medications or chemicals may cause
cataracts.
How are cataracts removed?
They are removed surgically, in most cases with an device that uses sound waves to
soften the cataract.
Will my eye be damaged if I choose not to have the cataract removed?
In most cases, no harm will be done by postponing surgery. However, you achieve
the best visual results if you don't wait too long for surgery. All cataracts are
not equal and some are more difficult to remove than others.
How much better will I see?
Will high blood pressure, diabetes, or breathing problems stop me from having
cataract surgery?
No, as long as these problems are under control.
Can cataract removal be performed on patients with glaucoma?
Should someone accompany me on the day of surgery?
Yes. A friend or family member will be able to visit with you in the recovery room and
drive you home. If you have no one available to assist you, ask our staff about a visiting
nurse.
Am I put to sleep for the surgery?
You may be put to sleep for about two minutes while local anesthesia is administered,
and you awake feeling very relaxed. You will be awake and comfortably relaxed during
the entire surgery.
Must I wear an eye patch after surgery?
You usually wear an eye patch the first day. Then for one week, you need to wear an eye
shield while you sleep, and an eye shield or glasses during the day to protect the
eye.
How soon can I use my "new" eye?
The day after surgery. Vision usually is hazy at first, but will become clearer each
day.
Will my activities be restricted?
Somewhat. You may resume normal activities such as housework or walking. However, you
should not do any heavy lifting or straining for one week, and you should always be
careful to avoid hitting your eye.
May I bend down after surgery?
Yes, if you don't have any complications after surgery, and you are careful to avoid
straining.
How soon can I drive my car?
You may drive as soon as your vision meets the requirements for a driver's license and
you are visually comfortable.
Will I still need to wear glasses if I have a lens implant?
A glasses prescription is usually needed for either reading, distance vision or
sometimes both, but it will not be a strong prescription requiring thick, heavy
lenses. Many patients find they can perform most, if not all, activities without
glasses.
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What is a cataract?