Posted on 01/25/2005 10:13:22 PM PST by neverdem
REALLY?
THE FACTS Glasses can bring a blurry world into focus, but some people suspect that by doing all the heavy lifting the glasses may speed the natural decline of vision. But ophthalmologists say this is an illusion.
How well a person can see is largely determined by the size of the eyeball, something a pair of glasses cannot change. The average eye is about an inch from the cornea, in the front, to the retina, in the back. When the eyes are either too large (shortsightedness) or too small (farsightedness), the cornea cannot properly focus images on the retina, and glasses can help compensate.
Dr. Robert Cykiert, an ophthalmologist at New York University Hospitals Center, said the contrast between poor and normal vision becomes more obvious when people wear glasses for a while and then take them off. But glasses have no lasting effect on eyesight.
Reading in the dark won't damage your eyes either, Dr. Cykiert said, though you may get a headache from all the squinting and straining.
THE BOTTOM LINE Glasses will not make your vision deteriorate more quickly.
scitimes@nytimes.com
Thanks for explaining this.
My 89-year-old mother, who has always loved to read, has found she can read better at some times during the day, than others. Allowing sunlight (coming through her window) to shine on the page, is helpful. (I've been checking into getting one of those Ott-lite lamps for her.)
But, aside from lighting, she finds she can see print better at some times than others. I wonder if her medications are affecting her pupils.
OK, I'll try........
20/20 vision is "normal". That means a person with "normal vision" can read the bottom line on the standard eye chart at a distance of 20 feet. So if you have 20/50 eyesight that mean that you have to be 20 feet away while those with "normal eyesight" can see it at 50 feet.
BTW, as a teen 'we' had a friend with 20/200 vision (almost legally blind). As such, he had to get a letter from his eye doctor so he could get a DL. He wasn't supposed to drive at night, which he did - that made for some 'fun rides'.
ping
Has anyone done a controlled experiment (maybe on animals, if PETA would allow it) to see whether long-term use of corrective lenses weakens vision?
Two things happen as you grow up.
First the shape of your eyeball changes as you grow. Most little kids are a bit farsighted. If your eye lengthens too much you end up nearsighted, not enough farsighted.
Also the lens in your eye bends to help focus the light on to the back of your retina. It also absorbs the UV light that would harm your retina but with time UV light changes your lens making it less flexible and decreases it's focusing abilities necessitating longer arms or reading glasses.
It's been studied and proven decades ago that glasses, which only bend light so that images seen are directly on the retina, do not effect the final outcome of either of the changes an eyeball goes through. No exercises can change this outcome.
Theses changes can be seen when people are in their last thirties, early forties.
"My 89-year-old mother, who has always loved to read, has found she can read better at some times during the day, than others. Allowing sunlight (coming through her window) to shine on the page, is helpful. (I've been checking into getting one of those Ott-lite lamps for her.)"
Get her a daylite lamp, and you should see a lot of improvement. Also, besure that her vitamin includes at least 250 mcg of Leutin per day.
"But, aside from lighting, she finds she can see print better at some times than others. I wonder if her medications are affecting her pupils."
I'm 66 and about 6 years ago, I went from quite near sighted to 20/10 in my left eye (my dominant eye) and 20/40 in my right eye. Also, I didn't need reading glasses any more.
A couple of years later, from November until Daylight savings came back, I needed to use my fly tying magnifiers to do the cross word puzzles and to read some books after dinner. During the daytime in our house and outside, I had no problem reading small print.
A friend who is an eye md said that it was the lack of sunlight and probably a shortage of Lutein do America's phobia not to eat eggs. He recommended a daylight bulb in my reading lamp and to go on Centrum Silver. The results were incredible in a week or so. Then, the next winter my wife bought a generic Centrum, and my inability to read in the winter after dark returned. I actually got a contact for evening wear for my right eye, and it worked. It was just a pain. Then I decided to go back to regular Centrum, and I haven't needed the contacts the last two winters.
In closing I think that many of us who are over 60 can read better in daylight with good sunlight. The use of the natural lights in the winter time can help in the evening or on cloudy days. Leutin is very important for healthy eyes and a must for most of us over 60.
Had the one in the left eye removed 8 years ago as it sat in the center of my field of vision. The other is not any where near removal stage.
There have been several theories that I'm aware of that have tried to explain the loss of near and distance focusing ability at around the age of 40-45. The oldest theory is probably that the muscles weaken, which has generally been shown to not be a major factor. The other is that the crystalline lens gets stiffer with age due to the absorption of UV light over our lifetime (resulting eventually in a cataract if we live long enough). This is almost certainly one of the factors. However, the most recent research indicates that because the crystalline lens adds layers each year that eventually it runs out of space and cannot flex far enough to focus in for the amount needed for reading or close work.
There are currently several companies trying different ways to either safely shave off some of the edges of the crystalline lens to provide more room, or to remove some of the surrounding (non-vital) tissue around the lens to make room for lens flexure. I haven't read anything on the results recently, but that was the "latest" theory. There's a lot of money at stake because the baby boomer market is huge and they certainly don't like wearing bifocals!
Ei'v bene waering glessas senci I saw there dan mi iyeseght his improdev darmitallacy!
The shape of the eye does change shape somewhat as it moves in the socket (elongating as we read or work close up). However, there is not a way to adjust the distance permanently and safely that I'm aware of. Most of the power of the eye is on the front of the eye in the cornea, which is what the RK, PRK, and lasik surgeries have all worked on. A small change in the front curvature makes a lot of difference in the focal point of light on the retina.
There are, of course, other reasons for decreases in vision capability, but if the decline started after age thirty, this is the most common reason. Usually, it affects our close focus vision, which is the reason people go to "reading glasses" after a certain age. Since my far vision is still fine, I wear one contact, and use my right eye to read, and my left eye (dominant eye, one used for shooting a firearm or looking through a camera viewfinder) for far vision.
Actually, when my son was five we had his eyes examined because he would soon be starting kindergarten, and dyslexia did run in the family. We wanted to know if there might be some problems in future.
To our great surprise, dyslexia was not his problem, the problem was that he was really seeing out of his left eye only, the right eye was 20/80 and he was "ignoring" the right eye. We had had no idea. But thirty days in an eye patch over the left eye corrected the right eye to 20/25, and his eyes have doing just great ever since.
Treat those young eyes early, because it's easier then.:)
Can i add my 2 cents worth?"I wonder why it( my vision) changed to begin with"? I wondered about that as well. My vision was 20/20 up till my mid 30's. My eye Dr. explained that as we age,constant pressure on the eye changes/inhibits the ability of the eye to focus.Objects far away or close up appear fuzzy,blurred ie out of focus.This is prob an over simplification(i'm not an MD),but that was the jist of our conversation.
He may think so, but get him tested, and it would be wrong.
No way, I'm not going to pay for him to get an eye exam.
Unless those exercises can change the shape of your eye, which is why one can't see clearly, exercises do nothing except strain your eyes.
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