Cataracts and Eggs

Picture this: You are in your kitchen making breakfast. You smack an egg on the outer edge of a frying pan gently prying open its cracked shell spewing its raw contents into the awaiting heated pan. Visualize the egg white. It s nearly transparent at this uncooked stage. But as it begins to heat up it starts losing its see-through transparency getting cloudier as it cooks finally reaching the point of being completely opaque white.

Okay now shift to the human body. Unless you ve already had cataract surgery there s a lens buried deep inside each of your eyes. This lens is what makes it possible for you to see clearly at different distances. Go ahead and shift your gaze from the print that you re now reading on this page to a wall across the room or out of a nearby window. Assuming that you don t need glasses and your eyes are otherwise healthy wherever you look the image should be clear. The best part...you don t have to do a thing it s all automatic just like digestion and breathing. You just aim your eyes and voila your lenses will automatically focus for you. This all sounds so simple but the complexity of neurological mechanisms that come into play here are mind-boggling.

Where exactly is the lens anyway?

Look at your eyes in the mirror. Go on get a close look. When you check off the eye colour section on your driver s license form you are essentially describing your iris. That s right...that ring of colour that you now see in the mirror is your iris and the round black opening at its centre is called the pupil. The lens sits directly behind your iris so when you look into your pupil in the mirror you are looking smack-dab into the lens centre.

If you could hold one of your lenses in the palm of your hand you d see that it is just about the same size and shape as an M&M candy. If you re young...say under 30...your lens would be fairly clear sort of like the example of the uncooked egg white. The lens consists mostly of water and protein molecules arranged in such perfect precision that light passes through it unobstructed.

As we age; however the protein begins to clump together and starts to cloud the lens. If you are over 50 your lens would probably look a bit cloudy and more like the egg white in the frying pan after it s been cooked for a while. This lens cloudiness is a cataract. The cloudier the lens becomes the more difficulty light has getting through. The vision therefore declines. A cataract is not as so many people have misconstrued a growth on the outside of the eye.

How fast do cataracts grow?

Generally the cause of a cataract is time. Certainly cataracts can be caused by things such as trauma or infection but most cataracts are age-related. If you live long enough you ll eventually get cataracts. But here s where people differ. An 80-year-old may have a very small amount of lens cloudiness and a 40-year-old may need cataract surgery. For most people though the earliest signs of cataract appear somewhere in their mid to late 50 s but usually at this point they are minor and do not affect vision.

Cataract Symptoms

As a cataract matures it will eventually start to cause blurry vision a yellowing or dullness of colors poor night vision and an increased sensitivity to light particularly headlights from oncoming cars. A growing cataract may also require frequent changes in eyeglass prescriptions.

When Should a Cataract Be Treated?

This is the $64 000 question. Discuss this with your eye doctor but generally it s up to you. Doctors will not usually look into your eye and say "Aha it s time to take out that cataract." Instead they will most likely put the ball in your court and ask you if you are meeting your visual needs. In other words does your vision prevent you from doing the things that you want or need to do in your life? If your decreasing vision doesn t bother you that much your doctor will most likely opt to keep a close watch on your cataracts rather than remove them. If however you are not meeting your visual needs then your doctor will discuss treatment.

And finally....treatment

At this point in time the only treatment for cataracts is surgical removal. Recent advances in technique and instrumentation have dramatically reduced the length of time it takes to perform the procedure as well as the recovery time. Nearly all procedures are now done on an out-patient basis using only local anesthesia (very often nothing more than eye drops). Simplistically put the cloudy cataractous lens is removed from the eye and replaced with a clear plastic implant that looks like a miniature hard contact lens.

Cataract surgery is one of the most common surgeries performed in Canada with over 150 000 operations done each year. Most people who have had the surgery generally report a higher quality of life because of their improved vision.

Prevention. Can anything be done?

Cataracts are a natural part of the aging process but a healthy lifestyle can have a protective effect. There are some studies that have shown that vitamin C taken regularly as well as estrogen replacement therapy may delay cataract formation but this issue remains controversial. Wearing sunglasses (starting early in life) to protect the eyes from harmful ultraviolet radiation may also slow down the growth of cataracts. We do know that smokers are three times as likely to develop cataracts as those who do not smoke.

If you haven t had your eyes examined in quite a while pick up the phone and make an appointment. Your doctor will be able to tell you exactly if you have the start of a cataract.

One thing is for sure. Cooking eggs will never again be the same.