What is a Cataract?
A cataract is a clouding of the normally clear, transparent lens of the eye. A cataract is not a tumor or growth of new tissue over or in the eye. Rather, it is a fogging and loss of clarity of the lens itself.
The lens is located in the eye just behind the iris and the pupil. Light entering the eye is focused by the lens onto the retina. When a cataract forms, the lens is no longer able to focus the light clearly. Therefore, your vision becomes cloudy. An early cataract may cause few problems with vision. If the cataract gets worse, sight can be partially or completely lost until the cataract is removed.
A cataract causes light to scatter at the level of the lens.
Scattered light causes a blurry image. Successful removal of the cataract allows the image to be seen clearly.
How Fast does a Cataract Grow?
Certain types of cataracts progress quite rapidly and cause cloudy vision within a few months. Fortunately, these are relatively uncommon. Most cataracts develop gradually and do not require surgery for many months or years. In some instances, surgery is never required.
What are the Causes of Cataracts?
There are many types of cataracts. Most are caused by chemical changes in the lens that partially result from the normal process of aging. These cataracts can rarely occur as early as age 30. There is now evidence that prolonged exposure to ultraviolet light can contribute to cataract formation. Ultraviolet light is a normal, invisible component of sunlight. Most exposure to ultraviolet light occurs when outdoors between 10:00 a.m. and 2:00 p.m., particularly in the summer season. Exposure to ultraviolet light can be reduced by wearing a hat with a brim and glasses that filter out ultraviolet light.
Other causes of cataracts include eye injuries and certain infections or diseases such as diabetes. There is new preliminary information that suggests that mild forms of vitamin deficiency can contribute to cataract formation. For this reason, it may be prudent to take one multivitamin per day. A recent study has suggested that the rate of formation of cataracts in women can be reduced by taking l 000 mg of vitamins E & C per day. There is no evidence that taking large doses of vitamins provides any benefit.
In rare instances, children can develop cataracts. If these are present at birth, they are called congenital cataracts.
What are the Symptoms of Cataracts?
The most common symptom of a cataract is cloudy or blurred vision.
Some people notice a haziness or milkiness of their vision, as if their glasses are constantly in need of cleaning. Double vision can occur as the cataract is forming. Glare or sensitivity to bright lights is another common complaint; at night, there may be halos around lights or scattering of the light from the headlights of oncoming cars.
Some cataracts first affect reading or other types of close work.
Other types of cataracts initially interfere with driving or seeing at a distance. Sometimes changing the glasses is helpful in restoring good vision. However, as the cataract worsens, stronger glasses may no longer improve sight.
When should a Cataract be Removed?
The appropriate time for cataract surgery depends upon the severity of your cataract and the degree to which it interferes with your normal daily activities. Selecting the right time for cataract surgery is a personal decision. If you are very active and use your eyes extensively for detailed work, you might benefit from cataract removal at an earlier stage than someone with less critical visual needs. You no longer need to wait for your surgery for the cataract to “ripen.” You are the one best suited to make the decision about having your cataract removed.
In a great majority of cases, a cataract does no damage by being left in the eye. In rare instances, when the cataract is left in the eye too long, the eye can become inflamed or develop glaucoma. If this occurs, then the cataract should be removed in order to prevent severe injury to the eye.
How are Cataracts Treated?
At present the only treatment for a cataract is surgery to remove it. Many other remedies for cataracts have been attempted. These have included medications, eye drops, vitamins, changes in diet, and resting the eyes. Unfortunately, none of these has proven successful in dissolving or clearing cataracts.
Fortunately, there have been tremendous advances in cataract surgery in the past several years. The chances for recovering good vision after surgery are now excellent, although severe complications can occur in 1-3% of patients. Due to recent advances, cataract surgery now causes remarkably little discomfort and inconvenience.
How are Cataracts Removed?
There are two main types of cataract operations currently in use.
In this technique, a tiny vibrating ultrasonic needle creates high energy sound waves that break the cataract into smaller particles. These particles are gently suctioned out of the eye. Phacoemulsification permits us to take the cataract out through a small incision, which speeds up healing after surgery, provides for a stronger eye, and reduces the amount of astigmatism that is present after surgery. Dr. Khater performs nearly all of his cataract operations using phacoemulsification.
In this method, part of the lens is extracted from the eye in one piece. The remainder of the cataract is removed from the eye using a tiny suctioning needle. This is also an excellent procedure, but it requires a larger incision and more stitches than does phacoemulsification. It also tends to cause other problems such as astigmatism, slower healing, unintended wound leaks, and other issues. Generally speaking, this is an obsolete procedure, and should only be used under very unusual circumstances.
Are LASERs used to Remove Cataracts?
Lasers are commonly used to remove cataracts. At this time, a laser can safely break up a lens prior to your doctor removing it from the eye. Additionally, lasers can be used to improve the precision of cataract surgery, by making “perfect” incisions and by managing astigmatism, two things that are difficult to do by hand. Phacoemulsification, which uses ultrasound, is commonly confused with laser cataract surgery, but does not involve the use of a laser.
Are Stitches (Sutures) Required for Cataract Surgery?
One of the most exciting new advances in cataract surgery is the ability to remove the cataract and implant an intraocular lens through a small incision. New techniques for making incisions have, in many instances, eliminated the need for sutures following cataract surgery. For some individuals, this type of incision is preferable. However, for other individuals, other types of incisions, ones that require sutures, will provide a better result for them. We, therefore, select the type of incision that is best suited for each patient’s condition.
What is a Secondary Cataract?
Following cataract surgery, we deliberately leave the back membrane of the lens in place to support the intraocular lens and protect against complications. In over 50% of the eyes, this membrane eventually becomes cloudy. This cloudiness usually develops 1-5 years after surgery. This clouding of the membrane is called a “secondary cataract.” The symptoms of this are often similar to those that occurred with the original cataract. Patients often tell us that their first evidence of a secondary cataract is the constant desire to try to clean their glasses.
If a secondary cataract develops, we can make a small opening in the middle of this membrane using the YAG laser. This can be done quickly and painlessly without requiring an incision in the eye. The membrane almost never grows back after laser treatment. The only exception is in children, in whom the membrane often regrows one or more times. This laser procedure is also what many people confuse with laser cataract surgery.
Will I have an Intraocular Lens Inserted During My Cataract Operation?
Removing the cataract is only the first step in recovering good vision. Since the cataractous lens has now been removed, we must provide an additional lens in order to help the eye focus light clearly. Following cataract surgery, there are three methods by which clear vision can be restored.
Intraocular Lens Implant (IOL)
Our preferred way to restore vision for nearly all of our patients after cataract removal is to insert an intraocular lens implant into the eye at the time of surgery. This clear implant is placed in the eye behind the iris and pupil in the same position as the natural lens, and it stays in the eye permanently.
Implanting an intraocular lens adds little additional risk for the surgery. Only very rarely does an eye “reject” an implant, and it is even rarer that a lens implant needs to be removed after surgery. Patients who have certain unusual eye conditions might not be good candidates for intraocular lens implantation. We will discuss this with you when planning your surgery.
An intraocular lens is permanently implanted in the eye after the cataract is removed.
It is possible to implant an intraocular lens in an eye that has had previous cataract surgery. This can be especially beneficial to those who are having difficulty using cataract glasses or contact lenses. Not all patients are good candidates for this surgery. However, secondary lens implantation can be a very rewarding operation for those who have become frustrated with cataract glasses or contact lenses.
A contact lens can restore good vision following cataract surgery, and there have been many advances in lens design and materials in recent years. Contact lenses do not cause the visual distortions that occur with cataract glasses. Unfortunately, there are several disadvantages with contact lenses. The major one is that one must learn to insert and remove the contact lens either every night or every few days. In addition, some people are not able to adapt to wearing a contact lens on the eye. Another disadvantage is that a contact lens can be easily damaged or lost, and improper care or use may cause eye infections.
These are thick, heavy glasses that cause a number of significant visual distortions, although the central vision is generally excellent.
Only rarely do we recommend the use of cataract glasses to correct vision after cataract surgery.
Are there Different Types of Intraocular Lenses?
There are countless varieties of intraocular lenses. All lenses contain a clear central portion for focusing the light (called the “optic”) and some type of flexible arms for supporting the lens inside the eye. The optic of the lens acts just as your natural lens once did, except that it cannot adjust its focus. As a result, you may need to wear regular bifocal glasses following surgery in order to get the best possible vision, especially for reading.
Recent advances in intraocular lens designs and surgical techniques have permitted us to implant lenses through small incisions. These incisions are so small that almost no astigmatism is created and, depending on the particular circumstances, sutures may not even be required to close the incision. Depending upon the condition of your eye, you may or may not be a candidate for one of these types of implants.
Another new type of implant has a bifocal built into it. In some patients, this type of implant may reduce or eliminate the need for reading glasses after cataract surgery. One type of bifocal implant has recently been approved by the FDA. Though it is not recommended for all patients undergoing surgery, it shows great promise for those who meet the carefully defined criteria for receiving this lens.
Additionally, implants have been created that can correct large degrees of astigmatism. In many patients, this type of implant may reduce or eliminate the need for distance glasses after cataract surgery.
There have been remarkable advances in cataract surgery in the past several years. We have gone from the time when people needed to lie still in bed for six weeks to an era in which outstanding vision is usually restored, often within a few days. We look forward to discussing any of these matters further with you. Also, please refer to our patient instruction letter for further information about the specifics of cataract surgery with us at West Texas Eye Associates .