YOUR HEALTH - MEDICINE 101

Cataracts
We humans, as a species, have evolved some remarkable organs, but none of them is more remarkable than our eye. We are, of course, creatures, we work best in the day, and it is the evolution of our eye that has allowed us to be so successful as a species. The eye works the same way a camera does, with light rays entering the structure here. The lens focusses the rays to land on the film, or retina, on the back of the eye. The lens is adjustable - just by looking up we automatically adjust the tension in the lens to refocus from up close or from far away.

However, as we age, the lens becomes less malleable, less able to change it’s shape and we find it hard to focus. That is why most of us have to add other lenses in front of our own eye’s lens to help focus the light rays.

And as we get older, the clear lens sometimes gets cloudy, preventing light from getting through easily. That's called a cataract. It’s the same word used to describe a waterfall. They can be caused by diabetes, kidney disease, medications or injury, but mostly it's just age. Half of us have them by age 65 and seventy percent after age 75.

Cataracts cause a loss of vision. It's usually a gradual and painless with blurring, difficulty reading and sometimes halos around lights or glare. The specific treatment for cataracts is to remove the damaged lens by surgery. It’s a little frightening to think of operating on your eye, but cataract surgery is now the most common operation performed after age 60 with about a 99% success rate.

Here’s how it’s done. A tiny incision is made in the white part of the eye, the sclera, under microscopic control. Then the capsule that surrounds the lens is entered and the lens itself is sucked out with a vibrating ultrasonic instrument. Without the lens, of course, light rays could not focus easily on the back of the retina so a new lens, one made of acrylic, is inserted to take the place of the old one. Here’s what a lens looks like, it’s a clear plastic with these purple nylon stays to hold it in place. The entire lens can be folded, slipped into a very small incision, where it expands to fill the spot, fitting perfectly. The surgery only takes about ten minutes, and because the hole made in the outer surface of the eye is small there is not even a stitches. Immediately vision is restored, the new implanted lens focusing light rays correctly on the back of the retina’s a remarkable procedure for a remarkable organ.