Narrator: This is Science Today. Many cataract patients have to wear prescription glasses after surgery because there's no way to predict how the eye will heal. But an implantable lens that can be perfectly adjusted after surgery using ultraviolet light, may someday offer an alternative.

Schwartz: The light adjustable lens is similar to a conventional implant that are placed in the eye – the surgery's the same, the recovery's the same, but the difference is that instead of getting a prescription for glasses, we can shine a special light onto this lens and change its power after the lens is in place and after the eye is healed.

Narrator: Dr. Daniel Schwartz of the University of California , San Francisco , teamed up with researchers from the California Institute of Technology to invent this new way to fine-tune a patient's vision.

Schwartz: With conventional cataract surgery, the patient has a cloudy lens, or cataract, and the cataract is removed by the surgeon and then replaced with a clear lens. Those lenses are nonadjustable, which means that the lens you have put in your eyes is a lens you're going to keep for the rest of your life.

Narrator: Schwartz hopes this procedure will be available in the U.S. by late 2009. For Science Today, I'm Larissa Branin.