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THE MAGNIFIER Issue #38, December 22, 2005
Newsletter from the Macular Degeneration Foundation, Inc.
P.O. Box 531313 Henderson, NV 89053
http://www.eyesight.org
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LETTERS TO LIZ:
Thomas in
Tucson writes, "Regarding the article in The Magnifier, September, 2005, about affirming one's MD. I have MD, and am accepting it. A few weeks ago I had a six-month exam with my optometrist. This fine doctor
spent more time examining my retinas than ever in the past. She used a bright slit lamp, and at various times placed a clear lens and a yellow lens between the lamp and my eyes. Finally, she moved back, and said,
"Your retinas look better than they did six months ago. I guess you are still taking the vitamins!" I am taking an eye supplement and my eyes seem to be improving. However, I feel my positive attitude is
a major factor."
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I AM YOUR EYE!
Learning how your eye/eyes work is important in helping to understand common problems with your eyesight and how various treatments or therapies
might help. Using the "first person" to describe the function of your eye, this text has been taken from YOUR BODY & HOW IT WORKS, by J.D. Ratcliff.
"For concentrated complexities, no other organ in
your body can equal ME. No larger than a Ping-Pong ball, I have tens of millions of electrical connections and I can handle 1.5 million simultaneous messages. I gather 80 percent of all the knowledge that you as an
individual absorb. You can think of me as a miniature television camera, even though I am much more sensitive than the costliest TV camera ever made. I am responsible for one of the greatest of all miracles -- - - - -
sight.
Today's world is giving me a hard time. I wasn't built for it. For your prehistoric ancestors, the main function for me was to see things at a distance - dangers to be avoided, game to be killed. Only lately
have I been called on for continuous close-up work.
Look at my anatomy and you'll understand why I am having difficulty adjusting to today's demands. First, my front window, which is my clear, dime-size cornea, starts
the seeing process by bending light rays into orderly patterns. Next, my pupil is an adjustable gateway for light. In bright sun it is nearly closed; on a dark night it is wide open. Up to this point there is
nothing about "seeing" that a cheap camera couldn't handle.
My wonders really begin with my lens that is a little envelope of fluid the size and shape of an oval vitamin pill. My lens is surrounded by a ring
of tiny, superbly strong, and unbelievably hard-working muscles. When they tense, my lens fattens for near vision; when they relax, it flattens for distant vision. This was a fine arrangement for your caveman
ancestors. Since they were mainly interested in things 20 or more feet away, the muscles were relaxed most of the time. But now you live in a close-up world that includes lots of reading, close-up paper work, watching
television, and staring at your computer. This keeps my ciliary muscles tensed much of the time. They grow tired.
In front of and behind my lens I have two fluid-filled chambers. In front the fluid is like water;
in back it is about the consistency of egg white. The watery fluid keeps me firmly inflated. Both fluids must be absolutely clear to permit passage of light. Those "specks" you see when you look at a
bright light are cellular remnants left over from your days in the womb when I was under construction. They will float aimlessly in your eye fluid as long as you live.
When you look at an object, the light passes
through my lens, which brings it into correct focus on my retina. My retina is a kind of onionskin wallpaper that covers the rear two thirds of my interior. It is less than a square inch yet my retina contains 137
million light-sensitive receptor cells: 130 million shaped like rods for black-and-white vision and seven million shaped like cones for color vision.
The rods are scattered all over my retina. Let a firefly pass at
night and a complex chemistry is initiated. The faint light bleaches rhodopsin, a purplish-red pigment in my rods. The bleaching process generates a tiny wisp of electricity, just a few millionths of a volt, far too
little to tickle a mosquito. This feeds into my straw-size optic nerve and is transmitted to your brain at about 300 miles per hour. The brain interprets the signals flooding in and identifies the object - a
firefly. All of this intricate electrochemical activity has been completed in about .002 seconds.
If my rods seem complex, my cones are far more so. They are concentrated in the fovea, a pinhead-size, yellowish
depression at the very center of my macula. This is the center for acute vision and helps you enjoy colors. A leading theory is that these cones also have bleachable pigments, one each for red, green, and blue. Like an
artist mixing paints on a palette, your brain blends these colors to make scores of other hues. If anything should go wrong with this intricate electrochemical process, you would be colorblind. In dim light, the activity of
your cones diminishes. Your color sense vanishes and everything becomes gray as your rods take over.
You see with me, but you see in your brain. A crushing blow at the back of your head, severe enough to
destroy the optical center of your brain, would produce permanent blindness. A lesser blow and you would see "stars" or a chaotic electrical disturbance. The real evidence of your brain's role is when you
dream. You "see" pictures, even with your lids closed in total darkness. If you had been born blind, you would dream in terms of other sensory stimuli: touch, sound, even smell.
You were not born
with the eyes that you have today. At birth, you could see only light and shadow. In the first few months you were nearsighted. To study your rattle, you held it 8-10 inches from your face. Also, your
eyes were poorly coordinated. I'd wander in one direction, my partner in another. However, a few months after birth we were moving in exact unison. By the time you were six, your vision was
excellent and at age eight your eye sight was at it's peak."
Stay tuned in our next edition for the rest of the story. . . . . .in the meantime, we wish each of our subscribers a Happy Holiday and a wonderful New Year!
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MAGNIFIER NEWSLETTER - AUDIO VERSION
An audio version of the current Magnifier is now available online from the Foundation's "Newsletter" web page.
Look for a gray arrow next to the archives. Most browsers able to show a FLASH video will stream and play the audio file.
http://www.eyesight.org/Newsletter/newsletter.html
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CONTACTING MDF
To speak to a support representative directly, you may call 1-888-633-3937. If you reach our voice mail, please speak slowly and distinctly.
ORDERING BOOKS & TAPES
When purchasing items from Amazon.com, please remember to use the MDF search box located at http://www.eyesight.org/Books/books.html . By simply originating your search from our website, Amazon
rewards the Foundation with a small commission from each product you order. Thank you.
MAKING CONTRIBUTIONS:
Please make checks payable to Macular Degeneration Foundation, Inc., P.O. Box 531313, Henderson, Nevada
89053, or you may use your credit card on our web site http://www.eyesight.org/Donations/donations.html . Your contributions make our services available as a support system for macular degeneration patients in the following
ways:
1. We provide toll-free lines for personal contact assistance.
2. We mail brochures and other printed materials upon request.
3. We support an award-winning web site that provides the latest up-to-date
information.
4. We fund research proposal grants to provide therapies for both the wet and dry form of AMD. Contributions marked "research" are used 100% for research.
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MDF was founded in 1992 by Edmund J. Aleksandrovich Ph.D (a victim of macular degeneration). It provides MD patients and their families with the information necessary to understand the disease, the latest news
concerning ways to cope with the disease, and supports the efforts of researchers to find a cure.
Subscribers who wish to cancel their subscription or change their email address may visit:
http://www.eyesight.org/Newsletter/newsletter.html .
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