What is a cataract?
A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people.
By age 80, more than half of all men and women either have a cataract or have had cataract surgery.
A cataract can occur in either or both eyes. It cannot spread from one eye to the other.
What is the lens?
The lens is a clear part of the eye that helps to focus light, or an image, on the retina. The retina is the light-sensitive tissue at the back of the eye.
In a normal eye, light passes through the transparent lens to the retina. Once it reaches the retina, light is changed into nerve signals that are sent to the brain.
The lens must be clear for the retina to receive a sharp image. If the lens is cloudy from a cataract, the image you see will be blurred.
What causes cataracts?
The lens lies behind the iris and the pupil . It works much like a camera lens. It focuses light onto the retina at the back of the eye, where an image is recorded. The lens also adjusts the eye's focus, letting us see things clearly both up close and far away. The lens is made of mostly water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it.
But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract. Over time, the cataract may grow larger and cloud more of the lens, making it harder to see.
How can cataracts affect my vision?
Age-related cataracts can affect your vision in two ways:
When a cataract is small, the cloudiness affects only a small part of the lens. You may not notice any changes in your vision. Cataracts tend to "grow" slowly, so vision gets worse gradually. Over time, the cloudy area in the lens may get larger, and the cataract may increase in size. Seeing may become more difficult. Your vision may get duller or blurrier.
If you have advanced lens discoloration, you may not be able to identify blues and purples. You may be wearing what you believe to be a pair of black socks, only to find out from friends that you are wearing purple socks.
When are you most likely to have a cataract?
The term "age-related" is a little misleading. You don't have to be a senior citizen to get this type of cataract. In fact, people can have an age-related cataract in their 40s and 50s. But during middle age, most cataracts are small and do not affect vision. It is after age 60 that most cataracts steal vision.
Who is at risk for cataracts?
The risk of cataract increases as you get older. Other risk factors for cataracts include:
Certain diseases, such as diabetes.
Personal behavior, such as smoking and alcohol use.
The environment, such as prolonged exposure to sunlight.
What are the symptoms of a cataract?
The most common symptoms of a cataract are:
Cloudy or blurry vision.
Colors seem faded.
Glare. Headlights, lamps, or sunlight may appear too bright. A halo may appear around lights.
Poor night vision.
Double vision or multiple images in one eye. (This symptom may clear as the cataract gets larger.)
Frequent prescription changes in your eyeglasses or contact lenses.
These symptoms also can be a sign of other eye problems. If you have any of these symptoms, check with your eye care professional.
How is a cataract detected?
A cataract is detected through a comprehensive eye exam that includes:
Visual acuity test. This eye chart test measures how well you see at various distances.
Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
Your eye care professional also may do other tests to learn more about the structure and health of your eyes.
How is a cataract treated?
Surgery is the only effective treatment. Surgery involves removing the cloudy lens and replacing it with an artificial lens.
A cataract needs to be removed only when vision loss interferes with your everyday activities, such as driving, reading, or watching TV. You can make an informed decision about whether cataract surgery is right for you.
In most cases, delaying cataract surgery will not cause long-term damage to your eye or make the surgery more difficult. You do not have to rush into surgery.
What are the cataract surgery?
A small incision is made on the side of the cornea, the clear, dome-shaped surface that covers the front of the eye. After the natural lens has been removed, it often is replaced by an artificial lens, called an intraocular lens (IOL). An IOL is a clear, plastic lens that requires no care and becomes a permanent part of your eye. Light is focused clearly by the IOL onto the retina, improving your vision. You will not feel or see the new lens.
Is cataract surgery effective?
Cataract removal is one of the most common operations performed all over the world. It also is one of the safest and most effective types of surgery. In about 90% of cases, people who have cataract surgery have better vision afterward.
What happens before surgery?
A week or two before surgery, your doctor will do some tests. These tests may include measuring the curve of the cornea and the size and shape of your eye. This information helps your doctor choose the right type of IOL.
You may be asked not to eat or drink anything 12 hours before your surgery.
What happens during surgery?
At the hospital or eye clinic, drops will be put into your eye to dilate the pupil. The area around your eye will be washed and cleansed.
The operation usually lasts less than one hour and is almost painless. Many people choose to stay awake during surgery. Others may need to be put to sleep for a short time.
If you are awake, you will have an anesthetic to numb the nerves in and around your eye.
After the operation, a patch may be placed over your eye. You will rest for a while. The Doctors team will watch for any problems, such as bleeding. Most people who have cataract surgery can go home the same day. You will need someone to drive you home.
What happens after surgery? Itching and mild discomfort are normal after cataract surgery. Some fluid discharge is also common. Your eye may be sensitive to light and touch. If you have discomfort, your doctor can suggest treatment. After one or two days, moderate discomfort should disappear.
When will my vision be normal again?
You can return quickly to many everyday activities, but your vision may be blurry. The healing eye needs time to adjust so that it can focus properly with the other eye, especially if the other eye has a cataract. Ask your doctor when you can resume driving.
If you received an IOL, you may notice that colors are very bright. The IOL is clear, unlike your natural lens that may have had a yellowish/brownish tint. Within a few months after receiving an IOL, you will become used to improved color vision. Also, when your eye heals, you may need new glasses or contact lenses.