Dr Maynard McIntosh
What Is a Cataract?
Cataract is a clouding of the normally clear lens of the eye that affects vision. A cloudy lens prevents light from focusing sharply on the retina. Cataracts are very common in older people. There is no medicine to prevent cataracts. However it is no longer a great threat to sight as it once was considered to be. The ophthalmologist will advise that most cataracts may be removed without major difficulty. There is therefore less likelihood of a person going blind who was diagnosed with cataract. A cataract can occur in either one 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.
Other Types of Cataract
Most cataracts are age related, but other types of cataracts do exist.
Secondary Cataract
Cataracts can form after surgery from other eye related problems such as glaucoma. Cataracts can also develop in persons with health problems such as diabetes. The use of the steroid prednisone and other medications can sometimes lead to cataracts.
Traumatic Cataract
Cataracts can also develop after a traumatic injury to the eye (for example, a hit in the eye), although it can take several years for this to happen.
Congenital Cataract
Some babies are born with cataracts, or develop them during childhood. These cataracts may be small and not affect the vision. If they do, the lens may need to be removed. Congenital cataracts can develop if the mother has an infection or uses drugs or alcohol while pregnant.
Radiation Cataract
Cataracts can develop after exposure to some types of radiation, radiation cataracts can form after a patient undergoes radiation treatment for cancer.
What Causes Cataract?
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 mostly of water and protein. The protein is arranged in a precise way that keeps the lens clear and allows light to 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 known as a cataract. Overtime, the cataract may grow larger and cloud a larger section of the lens, making it harder to see.
TREATMENT OPTIONS FOR CATARACT
Surgery is the only way to remove cataracts. If symptoms of cataract are not affecting your normal activities, surgery may not be needed. Sometimes a simple change in eyeglass prescription can delay the need for surgery.
PREVENTION OF CATARACTS
To reduce your risk of developing cataracts:
Protect your eyes from UVB rays by wearing sunglasses outside
Have regular eye exams
Stop smoking
Eat fruits and vegetables that contain antioxidants
Maintain a healthy weight
Keep diabetes and other medical conditions in check.
