How Does A Cataract Impair My Vision?

The eye uses a lens similar to a camera to focus light, allowing for clear sight. Over time, the natural lens begins to harden and opacify, resulting in blurry vision. This medical condition is known as a cataract. Cataracts usually form over the course of several years, leading to a very gradual loss of clarity. Cataracts are treatable and can be taken out during a common surgical procedure.

I can see clearly now

During cataract surgery, the ophthalmologist makes a small incision on the surface of the eye, also known as the cornea. Next, a piece of the capsule holding the natural lens in place is removed to allow access to the cataract. The cataractous lens is then broken up using a machine called a phacoemulsifier. The same device eliminates the pieces of the cataractous lens one by one until the eye is clear of debris. Finally, the surgeon places an artificial lens inside the capsule so the eye can see clearly once again.

The return of the cataract?

After cataract surgery, the new artificial lens functions as the natural lens once did to focus light. Because the eye’s natural lens is no longer present, there is no place for another cataract to develop. An artificial lens is unable to become cloudy like the natural lens once did. Therefore, cataracts cannot come back after cataract surgery. Over time, however, post-cataract patients can experience a haziness similar to a cataract. This phenomenon occurs in approximately 20% of patients and is known as posterior capsule opacification (PCO). PCO is not a clouding of the lens but rather the capsule that the lens sits in.

Blurry vision again

PCO is often the result of the eye’s natural healing process going a bit overboard. As the eye recovers from surgery, parts of the eye regenerate cells that were lost. In some patients, cells begin to grow on the back of the capsule, causing the capsule to become thicker. The extra thickness drives the haziness that patients can confuse for a second cataract. Such an event can happen months or even years after cataract surgery.

YAG, it’s your turn

An eye surgeon can correct PCO through a procedure called a YAG laser capsulotomy. The YAG laser sends a beam to the capsule and removes excess cells that cause the haze. The procedure requires no anesthesia or incision and should not cause any pain. The process takes about 5 minutes and at no time does anything come in contact with the eye.