A cataract is a clouding of the eye’s natural lens, which lies behind the iris and the pupil. The lens works much like a camera lens, focusing light onto the retina at the back of the eye. The retina transforms light to a neurologic signal that the brain interprets as vision. The lens also adjusts the eye’s focus, letting us see things clearly both up close and far away.
The lens is mostly made of 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.
Do cataracts develop quickly?
Cataract development is usually a very gradual process of normal aging but can occasionally occur rapidly. Many people are in fact unaware that they have cataracts because the changes in their vision have been so gradual.
Can a cataract occur in one eye and not the other?
Cataracts commonly affect both eyes, but it is not uncommon for a cataract in one eye to advance more rapidly.
Do many people have cataracts?
Cataracts are very common, affecting roughly 60% of people over the age of 60, and over 1.5 million cataract surgeries are performed in the United States each year.
Symptoms of cataracts
Cataracts are usually gradual and usually not painful or associated with any eye redness. At first a cataract has little effect on your vision. Gradually you may notice:
- that your vision is blurred a little, like looking through a cloudy piece of glass.
- difficulty with glare, often with bright sun or automobile headlights while driving at night
- dulled color vision
- increased nearsightedness accompanied by frequent changes in eyeglass prescription
- occasionally double vision in one eye
Causes of cataracts
Although the exact cause of cataracts is unclear, researchers are gaining additional insights about what causes these specific types of proteins (crystallins) to cluster in abnormal ways to cause lens cloudiness and cataracts. Aging is of course the most common cause. Some additional causes may be attributed to: significant eye trauma, exposure to excessive sunlight, smoking, family history, diabetes, and medications such as corticosteroids.
Cataract surgery
Cataract surgery is very successful in restoring vision. In fact, it is the most frequently performed surgery in the United States, with more than 3 million Americans undergoing cataract surgery each year. Over 90% of people who have cataract surgery regain very good vision, somewhere between 20/20 and 20/40.
During surgery,the doctor will remove your clouded lens and replace it with a Toric, Multifocal or Monofocal lens.