I am new to the Vision Improvement game. I have been reading extensively and have an overall basic understanding. Only this morning I was reading someone's article on this site (I thought) about his formula for reducing his prescription for astigmatism. I have lost track of the article, but if I remember it correctly it goes something like this: Reduce the cylinder by XX% and no bifocal correction. Can anyone out there point out a formula like this in the literature or does anyone have a personal experience they care to share.
Since this will be my first reduction, and since I'm a bit apprehensive I would appreciate any support I can get. I'm in my sixties and my current prescription is: 0D -050 -425 x026, OS -025 -475 x003. Both lines ar followed by a single +225 PAC (I think the latter is the correction for the over 40 crowd).
Overall my corrected vision is excellent. I can see both near and far well beyond what many people who have 20/20 vision can. However, I'm at the crossroads, I am either going to have my very well worn prescription specs replaced or work to get rid of them. I choose the latter and any encouragment will be appreciated.
Thanks in advance
Some additional questions and clarifications:
Ron> Since this will be my first reduction, and since I'm a bit apprehensive I would appreciate any support I can get. I'm in my sixties and my current prescription is: 0D -050 -425 x026, OS -025 -475 x003.
Otis> The OD is "right eye", and OS is left eye.
You seem to have a huge amount of astigmatism, of 4.25
Typical would be up to 1 to 1.5 diopters.
Could you check this again? Can you read a Snellen eye
chart? That would help clarify this issue.
The "add" is correct for your age.
The "add" or PAC of +2.25 diopters would be reasonable
for age 60, but check to make certain that
the PAC also has the same amount of astigmatism correction.
A call to your optometrist might help clear this issue up.
Just a suggestion.
Both lines ar followed by a single +225 PAC (I think the latter is the correction for the over 40 crowd).
Thank you for your interest and response Otis.
The prescription as presented is verbatim from the paper which I still have. If it helps, the test and prescription were done at Lenscrafters and it was for their version of the progressive lense. The prescription is 5 years old and the quality of vision is slipping for scratch and abrasion reasons as well as needing re-testing. I have made an appointment with a new doctor come Monday. But when I first got the glasses I could read 20/15 and better at times. Even at this point I can see much better near and at distance than people around me with supposed 20/20 vision.
The astigmatism numbers are very likely correct. When I got my first prescription at age 19 and several iterations along the way, the doctors all commented something to the affect that "I'd hate to have to fit you with contacts" or would simply write on the prescription "not approved for contacts".
The irony of it is that I probably needed lenses since I was a child. All during public school I could ace the Snellen Chart tests at 20/20 without fail simply by lowering my brow to cut down on the light reaching the eye. It wasn't until as a freshman in college that the amount of reading exposed the problem. I can still lower my brow and achieve 20/40 and better age 66. Without glasses at 6 inches I can read the finest print like a microscope, print that I couldn't begin to read with the glasses. Of course, the object according to Dr. Bates is to change the eye to achieve better vision while being relaxed and not straining which I can't do.
It is a bit paradoxical that there should be such a great deal of astigmatism and that I should be able to see so well functionally. The only reason I am required to wear glasses for the DMV is not because I flunked the exam but because I was asked the question "do you wear your glasses all the time" to which I answered "yes".
All this encourages me to give the "Dr. Bates Method" a try.
Thanks for your verification of 4 diopters of astigmatims.
Quite a few doctors will not precribe for astigmatism
less that 2 diopters, if you have 20/20 with no prescription.
About 10 percent of the primate population have a
small amount of astigmatism -- up to 1 diopter of it.
There is a "theory" that in school, we either develop
serious myopia or astigmatism. You might be
the latter case.
I perfer to go by the Snellen (even 20/50 and 20/60) if
I can play sports with no lens on my face. That works
with tennis and the like.
Obviously, once the DMV says "must wear glasses" then you
are stuck with it.
This may sound strange, but that astigmatism might
actually help with both your near and far vision!!!
(Just my guess.)
Just for MY curiosity, I will post a Snellen -- for your monitor.
I would be very curious to see what letters you can
read. (Guessing 1/2 the letters passes the line.)
If interested -- let us know.
Also, 4 diopters of astigmatism translates into
-2 diopters of spherical equivalent. And that
should translate into 20/140 vision with no glasses (at
Here is the chart.
<!-- m --><a class="postlink" href="http://www.smbs.buffalo.edu/oph/ped/IVAC/IVAC.html">http://www.smbs.buffalo.edu/oph/ped/IVAC/IVAC.html</a><!-- m -->
Just press "display" to get new letters. At 20 feet,
get a friend to press the "display" and verify your
Thanks again for your interest. I have a Snellen chart scaled to the correct dimensions posted on my wall. It's really interesting, when you put me to the test and asked me for the results. it now becomes and excercise in objectivity rather than subjectivity. I understand there is nothing to gain by reading the charts perfectly or to impress anyone but me. I have known for years that I have been able to prduce almost any results I want By various manipulations. I can read the chart 20/20 in the left and 20/30 in the right without glasses, given the proper amount of squinting and forward head tilting to cut down the amount of light with the brow. I have also noticed something that I hadn't previously. What image blur I see is only in one direction from the letter and it seems to correspon directly to the axis in the prescription. What I see is the dark black object letter with a very pale grey image of the same letter offset 1/2 the letter height higher, and in the case of the right eye, about 25 degrees clockwise. The same is true for the left except the image is shifted down about 1/8 the height of the letter at about 185 degrees. If I concentrate hard enought I can separate the two images and make a conscious decision as to what letter it is by disregarding the pale one.
It strikes me that this might be simpler to do than in the case of spherical corrections in which there must be a circular pattern to these pale images.
To answer the question directly, If I read the chart in a relaxed manner, with eyes wide open and no squinting or head tipping, I can read the chart without error at 20/70 with the right and 20/50 with left. For what it's worth, with correction, my binocular vision is 20/13.
when you read the chart you should neither be squinting or going wide eyed at the chart. Open your eyes in a perfectly normal fashion, no more or less than you would in other circumstances.