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Cataracts and Cataract Surgery

Overview

A cataract is a clouding of the natural lens of the eye. The natural lens focuses light rays onto the retina at the back of the eye in a way that is similar to a camera. A cataract can scatter or block light coming into your eye and impair your eye's ability to focus images clearly, resulting in blurry vision and glare.

Cataracts are the most common cause of treatable vision loss in the United States and cataract surgery is the most common type of eye surgery performed in this country. Almost 2 million cataract operations are performed in the United States annually.

Symptoms

Common symptoms of a cataract include:

• A painless blurring of vision
• Glare or light sensitivity
• Frequent eyeglass prescription changes
• Double vision in one eye
• Needing brighter light in order to read
• Poor night vision that can, in some cases, present glare problems

Vision symptoms caused by a cataract vary from person to person and can include problems with driving, reading, or work.

Both eyes are often affected, usually one before the other. If one eye remains normal, you may not notice a cataract in the other eye. Pain, redness, itching, or headaches are usually not associated with cataracts, but may be signs of another condition affecting the eye.

Causes

We don't know what causes cataracts. They usually occur as part of the normal aging process. Most cataracts progress slowly and can take months or years to develop before they affect vision. This process can be quite variable among individuals and we do not know why certain cataracts progress quickly and others slowly. For this reason, it is impossible to predict how fast a cataract will progress. Some factors that contribute to the development of cataracts include:

• Long-term exposure to sunlight
• Certain medical conditions such as diabetes and eye trauma
• Smoking
• Certain medications, mainly long-term use of oral or inhaled steroids

Studies have not been able to show that any medications, dietary supplements, exercises, or optical devices will help prevent or cure cataracts. However, protection from excessive sunlight may slow its progression. Therefore, we suggest that you wear sunglasses that filter out ultraviolet (UV) rays or clear glasses with an anti-UV coating.

Treatments

Depending on the severity of your condition and your symptoms, treatment options may include:

Vision aids. In the case of an early cataract, it may be possible to improve your vision by changing glasses. Working with a good, bright light may help, and sometimes a magnifying aid is useful. In some people, cataracts develop very slowly and do not affect the quality of their eyesight significantly.

Surgery. Once a cataract begins to cause vision loss that affects your ability to continue with your daily activities or, in the rare case where it puts your eye at risk for other complications, it may be time to consider surgery. Cataract surgery is very successful for most patients and most patients experience improvements in their vision. However, we can’t predict exactly how much your eyesight will improve after surgery.

Surgery

Cataract surgery is an outpatient procedure. You will be admitted into our outpatient surgery unit and, after your procedure and a short recovery period, go home the same day. You will need to arrange for someone to accompany you to the surgery unit and drive you home after the procedure.

Most of the time, the surgery is not painful, but you may experience minimal discomfort. We will give you medication to numb the eye either in the form of drops, or an injection. We will also give you mild sedation medication to help you relax during the operation, but you will be awake.

You will receive specific instructions about preparing for surgery and recovering afterwards, once your surgery has been scheduled.

Removing a cataract

• During cataract surgery, the cloudy lens is removed using a method known as phacoemulsification. This method uses ultrasonic technology that produces sound vibrations too high for humans to hear. These vibrations break the cataract into tiny particles which are then suctioned out.
• Once the cloudy lens has been removed, we replace it with an artificial intraocular lens (IOL) implant. The implant helps your eye focus after it has healed. 
• We will measure your eye before surgery in order to verify the type of implant that is best for you. 
• Cataract surgery is performed using microsurgical instruments and a special operating microscope. Tiny sutures may be used to close the incision, but usually sutures are not necessary with modern surgical techniques.

The Intraocular Lens Implant (IOL)

The intraocular lens, or "IOL," is placed in your eye at the time of cataract surgery and is designed to stay there permanently to focus the light entering your eye. If the natural lens were simply removed and nothing further done to focus light, your vision would be very blurry. Modern intraocular lenses block ultraviolet light to protect your retina.

In rare cases, an intraocular lens may need to be repositioned or removed months or years after surgery. Occasionally, an intraocular lens cannot be safely implanted at the time of surgery and glasses or contact lenses will need to be used instead.

We will measure your eye before surgery in order to verify the type of IOL that is best for you. Modern intraocular lenses may be monofocal, toric, multifocal or accommodative and we will help you select the type that is best for you.

A monofocal lens can focus images in the far distance, intermediate distance, or near distance but not all three at the same time. For example, with a monofocal implant selected for clear distance vision, you usually still need glasses to read fine print. If we select a monofocal lens to allow you to read up close without glasses, you will still need glasses to see clearly in the distance. Sometimes, depending on your individual needs and preferences, one eye can be corrected for distance and the other eye for intermediate or near. This is called monovision. This approach can make you less dependent on glasses, although it may mildly compromise a depth perception. Monofocal lenses cannot correct for astigmatism.

A toric lens can help correct an astigmatism, a common condition where the curvature of the cornea is irregular, causing blurred vision. The lens can help reduce your dependence on glasses for distance vision, although you will still need glasses for reading unless a monovision approach is used. We can help you decide if you are a candidate for this lens. This lens is not covered by your health plan benefits and is subject to an additional fee.

A multifocal/presbyopic lens is designed to focus on more than one zone simultaneously to reduce your dependence on glasses. This lens has several rings to help focus light at near and distance. This lens is not covered by your health plan benefits and is subject to an additional fee.

Accommodative lens. This lens is hinged to work in coordination with your eye muscles to mimic the way your eyes naturally focus. This allows the lens to move backwards and forwards to help the eye focus at various distances: near (reading), intermediate (computer) and distance. This can reduce your dependence on glasses, although you may still need them for the sharpest vision. This lens is not covered by your health plan benefits and is subject to an additional fee.

Risks

As with all surgery, complications can occur. There is a small possibility of bleeding, infection, inflammation or other complications including glaucoma, retinal detachment, and retinal or corneal swelling that could limit or decrease your vision.  

The natural lens of the eye is located in a capsule, known as the posterior capsule. When we remove the cloudy lens we leave this capsule in place to hold the intraocular lens in position. Sometimes a clouding of the posterior capsule may form months or years after successful cataract surgery. This clouding may cause symptoms of blurred vision similar to the original cataract.

Fortunately, blurred vision caused by a clouded capsule can be cleared with a quick and painless laser procedure called "YAG capsulotomy," performed in the clinic. 

If you are experiencing blurred vision long after cataract surgery, let us know.

After Your Surgery

• The sedation medications may make you feel a little groggy after the procedure. We recommend that you have someone available at home (or nearby) for the first night after surgery, to help with your medicines.
• Your eye will need time to heal and adjust so that it focuses in coordination with the other eye.
• You may notice that, at first, colors seem very bright, but as you heal you will get used to improved color vision.
• Your pupil may still be dilated for a few days after the surgery. This will make your eyes more sensitive to light and blur your vision.
• Many people drive better after cataract surgery because their vision eventually becomes clearer than before surgery.

Lifestlyle Changes and Management

In order to drive a private vehicle, the California Department of Motor Vehicles (DMV) requires that you can see 20/40 with both eyes tested together or at least 20/40 in one eye and 20/70 in the other eye. If your vision is less than this, you may be able to get a restricted license, which usually means you cannot drive on highways, or at night. If you are already scheduled to have cataract surgery, the DMV will often extend your license for up to 3 months. 

The DMV makes the final decision about your driving vision. We can only record what the eye examination shows and cannot make any driving recommendations to the DMV.

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This information is not intended to diagnose health problems or to take the place of specific medical advice or care you receive from your physician or other health care professional. If you have persistent health problems, or if you have additional questions, please consult with your doctor. If you have questions or need more information about your medication, please speak to your pharmacist. Kaiser Permanente does not endorse the medications or products mentioned. Any trade names listed are for easy identification only.