A cataract is a cloudiness that develops in the eye's lens and affects the vision. If left untreated, the condition can cause partial blindness. The lens of the eye mostly consists of protein and water. The protein is bonded in a precise way that keeps the lens clear and allows light to pass easily through it. A cataract develops when the structure of the protein molecules degenerates, causing them to clump together. This clumping eventually blocks out the light and obstructs vision. Many people liken a cataract to looking through frosted glass or wax paper.
A cataract may develop in one or both eyes and is easily remedied through surgery.
What Causes Cataracts?
There are a number of types of cataract. The most common kind develops with aging. When cataracts occur in younger people, they are usually caused by a chronic medical condition such as diabetes, eye trauma, or use of certain prescription drugs.
While the precise cause of cataract development is still the subject of research, many specialists consider that ultraviolet (UV) light is at least partially to blame. This assumption based on the finding that geographical areas with more hours of sunshine have a greater incidence of cataracts¹. In recognition of these findings, eyecare practitioners recommend wearing sunglasses and a wide-brimmed hat to lessen exposure to UV light. Other types of radiation have also been implicated in cataract development. A study conducted in Iceland in 2005 suggests that airline pilots have an increased risk of developing cataracts than non-pilots due to their exposure to cosmic radiation.
Radiation causes the body to produce highly reactive molecules known as free radicals. These unstable molecules cause damage to the body's tissues, including the lens of the eye.
Other risk factors include cigarette smoke, air pollution and heavy alcohol consumption.
Can Cataracts Be Prevented?
Since it is likely that cataract formation is accelerated by UV light, wearing eye protection that incorporates a UV filter may help delay or prevent the condition. Making sure your diet contains adequate antioxidants may also help allay tissue degeneration caused by free radicals. Consuming brightly coloured fruits and vegetables, as well as whole grains will provide you with a variety of antioxidant nutrients. You may also wish to take a supplement that has been formulated to help protect the eyes. Your London Drugs pharmacist will be pleased to help you find the right supplement for your needs.
How Are Cataracts Treated?
Cataracts that are causing visual difficulties are usually remedied during a surgical operation to remove the cloudy lens. In the past, eye doctors often waited until vision was heavily impacted before recommending the cataract be removed. Today, advanced surgical techniques enable the operation to be carried out as soon as a person's eyesight interferes with their daily life and ability to read, work, or do the things they enjoy.
During the operation, the affected lens is removed and replaced with a plastic lens. This enables the eye to see clearly after the operation. The plastic lens - known as an intraocular lens implant - remains permanently in the eye.
Cataract surgery is extremely successful in restoring vision and is the most frequently performed surgery in North America (more than 1.5 million cataract operations are performed every year). Nine out of 10 people who have had cataract surgery regain excellent vision, somewhere between 20/20 and 20/40.
1 Heck, D.E., Gerecke, D.R., et al., Solar ultraviolet radiation as a trigger of cell signal transduction. Toxicol. Appl. Pharmacol. 2004 Mar 15; 195(3):288-97