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Cataract Surgery
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Warren Hill, M.D.
Patient Information
Cataract Surgery - About Cataracts
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For Your Appointment, Call: 480.981.6111 |
Understanding Cataracts and Cataract Surgery
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As common as cataract surgery is, no two people undergoing this procedure are alike. The information presented here is not intended to take the place of the professional opinion or advice of your ophthalmologist, rather it is offered to help you understand the basics and feel more familiar with the subject.
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Topics:
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What are cataracts?
The word "cataract" comes from an ancient word meaning "waterfall". This is because for a person with a well-developed cataract, life is viewed as though seen through a sheet of water. This can also be compared to a window that is frosted or fogged with steam.
The diagram above shows the main parts of the eye. The lens is located behind the cornea (clear covering), iris (colored part) and pupil (dark opening) and is inside the posterior capsule (tiny sack that holds the lens in place).
A perfect lens is transparent, absolutely clear. Light travels easily through this lens, bending as it does to concentrate itself upon the retina that covers the back of the eye. The retina acts as a collector of information, which gathers the light transmission and sends it to the brain. The brain then amazingly gives us an image of whatever is in front of us, allowing us to "see". If the lens is frosted and the light rays are unable to pass through unhampered, the retina cannot collect accurate information. The image sent to the brain is then difficult to translate and what we see appears cloudy.
A healthy, youthful lens is also elastic and will "accommodate", or change shape, getting fatter for close objects and thinner for distant objects. This allows us to see both near and far, simply by shifting our gaze. As we age, this elasticity lessens, the lens becomes less flexible, and our vision becomes more fixed to a singular distance, thus the need for reading, or multi-focal glasses. Loss of accommodation occurs independent of cataract development.
These changes are a natural part of aging. Most people who develop cataracts are older adults. Almost everyone reaching their mid-sixties has some form of a cataract in one or both eyes. Cataracts do not cause irreversible blindness. They do not spread from one eye to the other. A cataract is not a growth that covers the surface of the eye, or a tumor, but simply a change in the clarity of the natural lens.
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The many parts of your eyes are very similar to the parts of
a camera. Both the camera and your eye have an internal lens that focuses an
image onto a film. In the eye, this lens is focused using incredibly small muscles, and the retina can be compared to film consisting of a thin layer of photosensitive cells.
If the lens in a camera were smudged or scratched, the pictures would turn
out blurred. Similarly, as the lens in your eye becomes cloudy with a cataract, your picture of the world is blurred. As a cataract becomes denser, it also takes on a brownish hue, resulting in an image that is both blurred and discolored.
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What causes cataracts?
As with most things that occur in the human body, the exact cause is unclear. People have been getting cataracts as far back as medical history has been
recorded, so this is not a modern phenomenon. If they live long enough,
everyone eventually gets them. It is just as much part of aging as getting
wrinkles or gray hair. Occasionally, people are born with cataracts, and
sometimes a cataract develops in one eye only after significant trauma, usually
from an impact of some sort like from a racquetball or golf ball. Exposure to excessive X-rays, intense heat or possibly too much sunlight can also cause cataracts. In addition, smokers tend to have a higher occurrence of cataracts than non-smokers. Other contributing factors may include family history, eye surgery, puncture wounds, medications such as corticosteroids, chronic inflammation known as uveitis, or diabetes. However, aging seems to be the main culprit.
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anterior cortical cataract - looks like a star
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mature or "ripe" cataract
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How do cataracts develop?
The lens is made of mostly water and protein, with the protein
arranged in a very special way that makes the lens clear and allows light to pass
through. As we get on in years, the tiny protein molecules begin to clump together, resulting in a gradual clouding of the lens. This cloudiness grows denser until light can no longer pass through the lens at all. Long ago, this process was referred to as "ripening", a ripe cataract being one that is completely opaque. Back then, surgeons waited until the cataract was ripe before removing it. This is no longer the case, and cataract surgery is now performed whenever the patient's vision and ability to function is impaired.
Not all cataracts develop the same. The most common type involves an even clouding of the entire lens. Others may develop in only one area and then spread out from there. Cataracts may take years to form, or they may occur rapidly within a few months. While cataracts can affect both eyes at the same time, they may develop at different rates.
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normal vision |
cataract free |
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| cloudy vision |
noticeable cataract |
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What are the symptoms?
Common cataract symptoms include poor night vision, a bothersome glare produced by bright lights, painless blurring of vision, and a fading or yellowing of colors. If this develops slowly over a period of years, it might not be immediately noticeable. There may be
little or even no perceived effects for quite some time. However, eventually, vision becomes a little blurred, like looking through a smudgy piece of glass. You
might notice that you are becoming more nearsighted, or experience double
vision (even with one eye covered). Light from the sun or a lamp might cause an uncomfortable glare, and when you drive at night, the oncoming headlights may seem overly irritating, causing you to stress over making your way safely. It becomes harder to read and do other normal tasks, and you may go through a series of changes in your eyeglass prescription.
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| cloudiness, glare and double vision |
Colors may not appear as brilliant as they once did. People might comment on the fact that you are now wearing brighter clothing, heavier make-up, or your hair is dyed an unfamiliar hue. These are all the natural compensations of viewing your world through cloudy-yellowed cataracts.
You don't have to be a senior citizen before noticing these symptoms. People can have age-related cataracts in their forties and fifties, although those are most often in the beginning stages and rarely affect vision. It is typically during the mid-sixties when vision becomes impaired enough to cause interference.
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How are cataracts detected?
Although you may think you have a cataract, there is only one way to know for
sure, by having an eye examination. If you are over sixty years old, you should
have an eye examination by a qualified ophthalmologist at least
once every two years. Once each year is not too much.
Take a look at the illustration at the top of this web page, and notice where
the pupil is. Pupils are the internal openings between the front and back of
the eyes, like tiny windows that you look through. Minute muscles make the iris
close or open, thus controlling the amount of light coming in. Your eye exam
should include dilating your pupils. This means drops are put into your eyes
that make your pupils open up, or enlarge temporarily in a fixed position.
A cataract can be detected without dilating the pupils, but doing so allows plenty of light onto the back of your eye. This is essential for finding potential problems. Getting a good view of the retina and optic nerve is used for early detection of eye diseases such as glaucoma and macular degeneration.
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When should they be removed?
Just having a cataract does not mean that you must undergo surgery. Even if your ophthalmologist finds a cataract, you may not need to have it removed for several years. In fact, you might never need cataract surgery. A change in your eyeglass prescription may satisfactorily improve vision
for a while. Magnifying lenses or stronger lighting may facilitate daily activities. However, if your cataracts interfere with your everyday activities, such as reading or driving, you do not have to put up with them.
The time to consider cataract surgery is highly individual. As a rule, when your vision falls below 20/40, you will notice a significant impact on daily functioning. To what degree will vary from person to person. A pilot, for example, may require surgery in the earliest stage of cataract development, while someone with considerably lesser demands might not be bothered by a much denser development.
Eventually, safety considerations may be a factor, as a developing cataract steadily limits a person's involvement in a normal, independent lifestyle.
Cataracts can be hazardous when they substantially interfere with your ability to see street signs, traffic lights or freeway exits, drive at night, step off curbs or steps, recognize faces, cook, iron, read medicine labels, or write checks, and sign binding documents.
As this is a highly individual matter, it is one you should discuss with your physician. By having your vision tested regularly, you can gather enough information to make an informed decision.
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How are cataracts treated?
Surgery is the only way to remove a cataract. There are no medications, eye
drops, exercises, or glasses that will cause cataracts to disappear. Your surgeon removes the clouded lens and replaces it with
a clear vision-correcting intraocular lens. Cataract surgery is a highly
successful surgery. In fact, it is one of the most common and highly successful of surgeries
performed in the United States, with over 1.5 million cataract surgeries
done each year.
Are cataracts harmful to your eyes?
Leaving a cataract in the eye is not harmful except in very rare situations. In most cases, surgery can be postponed for as long as the patient desires, or not done at all. The only side effect would be the less clarity of vision. Over time,
cataracts do increase in size and hardness, and if the cataract is very
advanced, the surgery can be more difficult to perform. However, even
then, the result is usually very good.
How long does a lens implant last?
They should last your entire lifetime. Intraocular lens implants are not known to "wear out."
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| Alcon SA60AT intraocular lens |
Can both eyes be done together?
No. Cataract surgery is best performed on one eye at a time, to enable you to use one eye while the other is healing.
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How is cataract surgery performed?
The surgeon operates while looking through a highly specialized microscope, designed exclusively for this purpose. A very small, beveled incision, less than 1/8 of an inch, is made at the edge of the "clear cornea" (see illustration at top of this web page for location). The clear cornea is the transparent covering of the front of the eye.
Through the tiny incision, a microsurgical, ultrasonic, oscillating probe is inserted, which gently fragments the cloudy lens, using high frequency sound waves. Simultaneously, this same instrument suctions out the fragmented pieces. This process is called "phacoemulsification". The posterior capsule, an elastic bag-like membrane that held the lens, is left in place.
The incision is commonly called "self-sealing" because the eye's natural internal pressure holds the incision tightly closed allowing the eye to heal without stitches. The chances of developing astigmatism (distorted vision) after surgery are significantly decreased by eliminating stitches, which tend to pull the eye's surface slightly out of its natural shape.
Once all the minuscule bits of the cataract have been removed, a tiny new clear implant lens is folded, inserted through the small incision, and allowed to open up inside the posterior capsule. Occasionally, a replacement lens is not implanted, or a different type may be placed outside of the "bag". Your surgeon will make this determination based upon whatever is best for your eye.
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The surgery typically takes 20-30 minutes, and is performed on an outpatient
basis. This means that you will have the surgery and then go home, usually around 30 minutes afterwards. Most of the time only local anesthesia is used, so you will be awake for the entire process. After the surgery, you are taken to the recovery
room and then released. You will need someone to drive you home.
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Dr. Neal Nirenberg, MD, FACS
Board Certified Ophthalmologist |
Do lasers remove cataracts?
No. Lasers are not part of a cataract operation. Cataracts are removed
using ultrasonic sound waves, not laser light. However, lasers are used for the removal of "capsular haze", which is a thin film of scar tissue that occasionally forms on the posterior capsule behind the implant lens. This is painless and occurs for a small percentage of patients who have undergone cataract surgery, causing the vision to temporarily be blurred again. Patients sometimes think their cataract has "grown back", but it hasn't. Once a cataract has been removed, it will not reoccur.
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A special Nd:YAG laser is used to remove capsular haze. An opening is made in the
scar tissue with the laser, allowing vision to be restored.
With modern intraocular lens implant designs, and materials, the incidence of posterior capsule clouding has fallen to approximately one percent.
Click here for an inside view of scar tissue removal by laser.
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| A strange new world. |
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Is cataract surgery scary or painful?
All this information about cataracts and surgery might seem a little frightening to you. It is perfectly normal to be a bit apprehensive before any unfamiliar experience, however, be assured that the great majority of our patients say their surgery was remarkably pleasant, and that pain was not even a consideration. We will do everything possible to make sure you are completely comfortable throughout the entire procedure.
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During your surgery, you will be given a relaxant to enhance calmness and neither see nor feel any part of the surgery. Afterwards, we will call you that evening to see that you are doing well. The next morning, you will visit with your physician to further cover any concerns you might have. We are here to help.
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Something worth celebrating! |
What is the success rate?
This is one of the most successful of all surgeries and difficulties are unlikely. As with any surgery, there are some risks associated with cataract surgery, and complications are possible during or after the procedure even with the most excellent care. Those complications most commonly seen are associated with unusual eye anatomy (very long or very short eyes), certain inherited eye diseases, and prior trauma. Possible complications include bleeding, infection, or the presence of glaucoma, corneal clouding, swelling of the center of the retina, retinal detachment, decreased vision, or in exceptionally rare cases, loss of the eye itself. It is impossible to predict in which patients these complications will occur. Fortunately, the risk of these complications is minute.
There are times when a cataract can be removed successfully but vision is not improved because
of other conditions or diseases of the eye. One such disease is macular degeneration. In this condition, the central part of the retina — the area that is critical for "fine" seeing — is damaged. Occasionally, this condition cannot be diagnosed prior to the cataract operation because the presence of the cataract may prevent the ophthalmologist from seeing the macula in sufficient detail.
In addition, other pre-existing conditions of the eye can limit vision after
the operation, such as diabetes and glaucoma. All such preexisting conditions
limit the eye's ability to regain normal vision, even if the cataract operation
is successful. It is important to remember that cataract removal has a high success
rate. It is most likely that your vision will be remarkably improved, and that
you will be able to do things that you were not able to do before the operation.
What is the recovery time?
Not so long ago, cataract surgery used to involve making a large incision to
remove the cloudy lens, and patients were often brought into the hospital
overnight or for several days. Now with the aid of new technologies, the
surgery can be performed through a very small incision, and the recovery time is significantly shorter, and usually occurs on an outpatient basis.
The day following your surgery, you will have an office appointment to ensure that you are healing properly. Your eye patch will be removed, and at that time your vision could be blurred from ointments associated with eye surgery, or you might see quite clearly, every patient is an individual and heals somewhat differently. Over the following weeks, visual clarity progressively improves, and after one month, the eye is typically healed and ready for refracting for new glasses. Follow-up visits are usually scheduled for the next day, one week, and then one month after surgery. During this time you will be using eye drops to help the eye to heal and to prevent infection.
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It is a good idea to accept some help! |
Will this impact on my activities?
Your sight will usually improve within a few days, although complete healing may take several months. It is a good idea to have some help at home if you can, especially if you find it difficult to put your eye drops in. For the first four days following cataract surgery, we ask you to avoid any and all heavy lifting or bending over that bring your head below the level of your heart. After that, and for the month following surgery, you can resume most of your normal activities, but minimize lifting, bending, and straining. Carrying reasonably lightweight objects, such as a purse or a small bag of groceries, is usually fine.
You will also be asked to avoid getting water in the operated
eye for one to two weeks. Water that is normally safe for showering and drinking has bacteria in it that can possibly cause an infection where the incision was made in your eye. Wash your hair leaning backwards rather than forwards, or better yet, have someone else wash it for you. Avoid swimming. You don't need to stay indoors, but try to avoid being out in the wind, as something might blow in your eye. You'll need to keep your hands out of your eyes as well. Your surgeon may give you an eye-shield to wear at bedtime, to inhibit your rubbing or pressing on the eye in your sleep. Avoid eye make-up for six weeks. As for returning to work or driving, this varies from one patient to another and the kind of work involved, and should be discussed with your doctor.
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Alcon SA60AT intraocular lens in place
(eye is dilated - otherwise you would
not see the lens) |
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Will I see better afterwards?
Over 95% of cataract surgeries improve vision. If having a cataract is the
cause of your decreased vision, then there is an excellent chance that
removing it will improve clarity. If you have an additional problem (such as
macular degeneration, prior uveitis,
retinal detachment, diabetic retinopathy, or glaucoma) a determination will be made as to which issue needs to
be addressed, and when. Cataract surgery can be successfully carried out
even in the setting of most of these other eye conditions.
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You will mostly likely have
to wear glasses for reading.
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Will I need to wear glasses?
Yes, most likely you will. Once a cataract has been removed, light can once again pass undistorted through the cornea and the newly implanted artificial lens, to the retina in the back of the eye. However, you may still be required to wear glasses to see more clearly because the incoming light needs to be focused directly on the retina. If you eye cannot do so on its own, eyeglasses provide that focus.
In addition, the artificial implanted lens cannot change shape for close vision the way a natural, youthful lens
does. A natural lens accommodates, or changes shape, to bring objects
into focus at distance, or close up. The intraocular lens implant provides clearest vision at a single focal distance, with the great majority implanted to correct for distance vision. This means that an eye focused for distance will have sharpest vision for activities such as driving, but would still require bifocal lenses or reading glasses in order to see clearly at close range.
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| The Zeiss IOL Master |
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How do I prepare for surgery?
There is not a lot that you must do. A comprehensive eye
examination is the
first step. Be sure to inform your ophthalmologist of all medications you are
presently taking, and ask if you should continue your usual dosages. During your
examination you will be evaluated for any special medical risks. Then, your eyes
will be measured to determine the proper power of the intraocular lens that
will be inserted during surgery. When the surgery date is set, you will be
given a simple list of preoperative instructions.
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