What is Cataract?
The lens of the eye is much like the lens in a camera. It is normally clear and helps to focus light rays that pass through it on the retina in the black of the eye
(like the film in the camera).
A “Cataract’ is a clouding of the normally clear lens of the eye. As the cataract develops, it reduces the light rays reaching the retina.
WHAT CAUSES A CATARACT?
Cataracts are a normal part of aging. Everyone eventually gets cataracts if they live long enough. The lens is made of mostly water and protein. The protein is arranged in a specific way that keeps the lens clear and allows light to pass through it. As we age, some of the protein may clump together and start to cloud a small area of the lens. This is our understanding of the cause of an age-related cataract. Over time, the cataract may become denser or cloud more of the lens, making it more difficult to see.
WHAT ARE THE SYMPTOMS OF CATARACTS?
You may not notice any symptoms with early cataracts. As a cataract becomes more advanced, you may notice a decrease in clarity of vision, which is not fully correctable with glasses.
Not all cataracts cause problems. A cataract starts out small. It has little effect on vision at first. As the cataract progresses, you may notice some of the following symptoms.
Cloudy, fuzzy, foggy or filmy vision (as if looking through a dirty window)
Inability to see colours brightly - colours appear faded, dull
Frequent changes in your eyeglass or contact lens prescription
Problems driving at night because of headlights
Problems with glare from lamps or sunlight
SIGNS OF CATARACTS
Family members of a person affected by cataracts in both eyes may notice he or she appears not to be seeing as well as previously. The eye will appear normal to the untrained observer, unless the cataract is mature and white. In that situation the pupil of the eye, which normally appears black, will look grey or white to the observer.
WHAT ARE THE DIFFERENT
TYPES OF CATARACTS?
Age-related cataract: Most cataracts are related to aging.
Secondary cataract: Cataracts are more likely to develop in people with certain other health problems, such as diabetes. Also, cataracts are sometimes linked to steroid use.
Traumatic cataract: Cataracts can develop from an eye injury, soon after or years later.
Congenital cataract: Some babies are born with cataracts or develop them in childhood, often in both eyes. These cataracts may not affect vision. If they do, they may need to be removed.
HOW IS CATARACT DIAGNOSED?
Cataracts are relatively simple to diagnose by an ophthalmologist or an optometrist during a routine eye examination. It is important, when making the diagnosis of cataract, to also examine the entire eye for evidence of any other eye disease which may be compromising the vision. In addition to taking a medical and ocular history and visual acuity test, the ophthalmologist will check eye movements and pupillary responses, measure the pressure inside the eyes and examine the front and back of the eyes after the pupils have been dilated with drops.
HOW IS A CATARACT TREATED?
People with early cataract will find that changing their glasses, using sunglasses to decrease glare and having better lighting to read can significantly alleviate their symptoms. Magnifying lenses for close work and reading fine print may also be helpful.
Many cataracts are not bothersome, causing few symptoms. In that situation, no surgical treatment is necessary. However, the only true treatment for cataract is surgical removal of the cloudy lens. Surgery is suggested if the patient loses the ability to perform necessary activities of everyday life, such as driving, reading, or looking at computer or video screens, even with glasses, and there is the expectation that vision will improve as a result of the surgery.
Depending on a patient's specific visual needs, surgery is sometimes done on cataracts that are not very dense or surgery can wait until the cataract and the vision gets more cloudy. Patients' responses to cataracts vary. A cataract in only one eye may be disturbing to a particular patient and may not cause significant symptoms
in another patient.
Cataracts usually do not harm your eye, so you can have surgery when it is convenient for you. Once you understand the benefits and risks of surgery, you can make an informed decision about whether cataract surgery is right for you.