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 population 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.
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.
Types of Cataracts
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.
Causes of 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. Apart from getting older, the other common causes of cataract include:
- Medications, such as steroids
- Eye surgery for other eye conditions
- Other eye conditions.
Risk Factors for Cataracts
- A history of cataracts in your family
- Lifestyle factors, such as poor diet
- Overexposing your eyes to sunlight
- Taking steroid medicines (medicines that contain powerful chemicals called hormones) for a long time
- Certain health conditions, such as diabetes
Symptoms of Cataracts
Cataracts generally develop gradually and although symptoms vary there are some symptoms that most people experience. Most people will eventually develop a cataract in both eyes, though one eye may be affected before the other.
- When your cataract starts to develop, you may feel your sight isn’t quite right. For example, if you wear glasses you may feel that your lenses are dirty, even when they’re clean. Gradually, you may find your sight becomes cloudier and more washed out. Edges of stairs or steps become more difficult to see and you may feel you need a lot more light to read smaller print.
- Lights can seem to glare, or you may find that the headlights of a car dazzle you more than they used to.
- Slight change in your color vision – things may appear more yellow than before. This often happens if one eye develops a cataract first and colors look different when you compare one eye with the other.
- Increased difficulty seeing at night
- Change in the eye’s refractive error
Treatment of Cataracts
The only effective treatment for cataracts is surgery to remove your cloudy lens and replace it with an artificial lens implant. This is done by an ophthalmologist (eye specialist) at a hospital. Lasers aren’t used to remove cataracts and there is no evidence to suggest that changing your diet, taking vitamins or using eye drops can cure cataracts. The operation to remove your cataracts can be performed at any stage of their development. There is no longer a reason to wait until your cataract is “ripe” before removing it. However, because any surgery involves some risk, it is usually worth waiting until there is some change in your vision before removing the cataract.
Cataract surgery usually takes about 30 to 40 minutes and most people go home from hospital a few hours later. It is usually done with a local anesthetic, which means you will be awake during the operation but you won’t feel any pain. To remove the cataract, the ophthalmologist needs to remove the natural lens in your eye and replace it with a plastic lens implant. The most common way to remove cataracts is called phacoemulsification. This technique uses high frequency sound energy to break up your natural lens with the cataract.
Complications from Cataract Treatment
Cataract operations are generally very successful, with a low risk of serious complications. The most common risk is developing a condition called posterior capsule opacification (PCO), which causes cloudy vision to return. If this happens, you may need to have laser eye surgery to correct it.
Get Free Media Grabber for Android
- Seeing Is Believing With Cataract Surgery (sacbee.com)
- Medical Watch: Cataract surgery at a much younger age (wwltv.com)