Cataracts is the clouding of the eye’s natural lens. The lens lies behind the iris and the pupil. When a person has cataracts, they may have difficulty seeing. Cataracts affect vision by scattering incoming light.
The lens is positioned near the front of the eyeball. It is protected by the cornea, which covers the front of the eyeball. The purpose of the lens is to focus the light waves that enter the eye. Muscles around the lens can change the shape of the lens. In this way, objects both close at hand and far away can be brought into focus.
There are many misconceptions about cataracts. For instance, cataracts do not spread from eye to eye, though they may develop in both eyes at the same time. A cataract is not a film visible on the outside of the eye, is not caused from overuse of the eyes, and using the eye does not make it worse. Cataracts usually develop gradually over many years; rarely over a few months. Finally, cataracts are not related to cancer, and having a cataract does not mean a patient will be permanently blind.
· Congenital disorders
· Genetic abnormalities
· Traumatic cataracts
· Complicated cataracts
Other causes of cataract are stress and strain; excessive intake of alcoholic drinks, sugar, and salt; smoking; certain physical ailments such as gastro-intestinal or gall-bladder disturbances; diabetes; vitamin deficiencies; fatty acid intolerance; ageing; radiation; side-effects of drugs that have been prescribed for other diseases.
Signs and Symptoms
The earliest signs of cataracts may mimic other eye conditions including macular degeneration. Many patients will notice they have more trouble seeing unless they use more intense lighting. Still others will notice they have difficulty pointing out finite details when reading or working.
There are several common symptoms of cataracts:
· gradual, painless onset of blurry, filmy, or fuzzy vision
· poor central vision
· frequent changes in eyeglass prescription
· changes in color vision
Detection of Cataract
The presence of a cataract can be spotted with the help of a complete eye examination by an ophthalmologist who may as well discover any other conditions that may be responsible for haziness of vision or other difficulties pertaining to the eyes.
Till date, no medication or diet has proved effective in checking the development of cataracts, and there is no medicine that can rectify a clouded lens.
The cataract operation
In the past, surgeons often waited until vision was very poor before removing the cataract. Now, the operation is usually carried out as soon as eyesight interferes with everyday activities.
Before the operation, a pre-operative assessment is done by the eye team. Usually a local anaesthetic is given before the operation, so the patient will be awake but feel nothing in the eye. The eye specialist will tell the patient what is happening throughout the procedure, and the patient will be made to feel relaxed and comfortable.
Cataract surgery is very successful in restoring vision. In fact, it is the most frequently performed surgery in the United States, with over 1.5 million cataract surgeries done each year. Nine out of 10 people who have cataract surgery regain very good vision, somewhere between 20/20 and 20/40.