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. 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.
The same scene as viewed by a person with cataract
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.
Researchers suspect that there are several causes of cataract, such as smoking and diabetes. Or, it may be that the protein in the lens just changes from the wear and tear it takes over the years.
How do cataracts affect vision?
Age-related cataracts can affect your vision in two ways:
- Clumps of protein reduce the sharpness of the image reaching the retina.
The lens consists mostly of water and protein. When the protein clumps up, it clouds the lens and reduces the light that reaches the retina. The clouding may become severe enough to cause blurred vision. Most age-related cataracts develop from protein clumpings.
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.
2. The clear lens slowly changes to a yellowish/brownish color, adding a brownish tint to vision.
As the clear lens slowly colors with age, your vision gradually may acquire a brownish shade. At first, the amount of tinting may be small and may not cause a vision problem. Over time, increased tinting may make it more difficult to read and perform other routine activities. This gradual change in the amount of tinting does not affect the sharpness of the image transmitted to the retina.
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 cause problems with a person’s vision.
Who is at risk for cataract?
The risk of cataract increases as you get older. Other risk factors for cataract include:
- Certain diseases (for example, diabetes).
- Personal behavior (smoking, alcohol use.
- The environment (prolonged exposure to ultraviolet 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.
Are there different types of cataract?
Yes. Although most cataracts are related to aging, there are other types of cataract:
- Secondary cataract. Cataracts can form after surgery for other eye problems, such as glaucoma. Cataracts also can develop in people who have other health problems, such as diabetes. Cataracts are sometimes linked to steroid use.
- Traumatic cataract. Cataracts can develop after an eye injury, sometimes years later.
- Congenital cataract. Some babies are born with cataracts or develop them in childhood, often in both eyes. These cataracts may be so small that they do not affect vision. If they do, the lenses may need to be removed.
- Radiation cataract. Cataracts can develop after exposure to some types of radiation.
How is a cataract detected?
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 eye.
How is a cataract treated?
Surgery is the only effective treatment of cataracts. It is recommended when you have difficulty performing your daily activities or doing things you enjoy. Advancements in technology have made cataract surgery one of the most successful forms of surgery performed today. 95% of the patients who have had cataract surgery enjoy excellent vision. Our cataract specialists perform the most advanced type of surgery using the latest techniques, including the «no injection», «no stitch» surgery. Patients are routinely sedated intravenously. The latest process called phacoemulsification is used to remove the cataract with sound waves. A small instrument is placed through a tiny incision. Sound waves break up the cloudy lens into microscopic fragments, which are gently removed. Most of the time, the incision is self-sealing, requiring no sutures.
When the cataract is removed, it is replaced with an intraocular lens (IOL). By carefully measuring many parts of the eye before surgery using the latest technology, our cataract specialists carefully select an intraocular lens for each eye. Some patients opt for the latest lens technology called a multifocal or accommodative lens, which may allow for clear vision both at distance and near usually without the need for glasses. For those patients who have had astigmatism, a Toric or astigmatism correcting lens can be used. Others may choose a monofocal lens often allowing for clear vision at distance without glasses. These patients usually require reading glasses. All the most advanced intraocular lens options are available at our clinic. Your cataract specialist will discuss these options with you at the time of your examination.
Is cataract surgery effective?
Cataract removal is one of the most common operations performed in the United States. It also is one of the safest and most effective types of surgery. In about 90 percent of cases, people who have cataract surgery have better vision afterward.
What if I have other eye conditions and need cataract surgery?
Many people who need cataract surgery also have other eye conditions, such as age-related macular degeneration or glaucoma. If you have other eye conditions in addition to cataract, talk with your doctor. Learn about the risks, benefits, alternatives, and expected results of cataract surgery.
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 intraocular lens (IOL).
You may be asked not to eat or drink anything 12 hours before your surgery.
What happens during surgery?
At the 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 15 minutes and is almost painless. Many people choose to stay awake during surgery. 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. Your medical 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.
For a few weeks after surgery, your doctor may ask you to use eyedrops to help healing and decrease the risk of infection. Ask your doctor about how to use your eyedrops, how often to use them, and what effects they can have. You will need to wear an eye shield or eyeglasses to help protect your eye. Avoid rubbing or pressing on your eye.
When you are home, try not to bend from the waist to pick up objects on the floor. Do not lift any heavy objects. You can walk, climb stairs, and do light household chores.
In most cases, healing will be complete within eight weeks. Your doctor will schedule exams to check on your progress.
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.
What can I do if I already have lost some vision from cataract?
If you have lost some vision, speak with your surgeon about options that may help you make the most of your remaining vision.
What can I do to protect my vision?
Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataract. If you smoke, stop. Researchers also believe good nutrition can help reduce the risk of age-related cataract. They recommend eating green leafy vegetables, fruit, and other foods with antioxidants.
If you are age 60 or older, you should have a comprehensive dilated eye exam at least once every two years. In addition to cataract, your eye care professional can check for signs of age-related macular degeneration, glaucoma, and other vision disorders. Early treatment for many eye diseases may save your sight.