Author Topic: Can the eye grow shorter?  (Read 6266 times)

Offline ScientificMind

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Can the eye grow shorter?
« on: December 21, 2014, 11:40:12 PM »
Hello fellow myopes/myopia preventers! I am so happy to have found this community for myopes! I have no doubt that plus lens therapy works. My belief in it is firmly supported by science, logic, and personal experience. I only regret that my parents and I did not know about earlier, which could have prevented my current condition of about -3.25 myopia.


Anyways, I started this topic to form a discussion about the theories of plus lens therapy.
There are two theories that supporters use to explain how plus lens therapy works. I made up the names for these theories myself as summaries, which basically only disagree on if the eye could grow shorter.


1).Only Longer Theory: Some of the pioneers of plus lens therapy such as Donald S. Rehm (author of the Myopia Myth and inventor of the patented myopter) believe in this theory believe that spasms develop in the eye after long periods of near work, and this spasm causes slight degrees of myopia (better than -1D). This theory states that plus lens can ELIMINATE MYOPIA ONLY WHEN THE EYES ARE AT THIS STAGE. When the spasm is allowed to continue or intensify through further near work, the spasm then causes the eyes to grow longer, in attempt to cause future near work to not cause the eyes to spasm. This theory thinks that myopia CANNOT be eliminated at this stage, because the eye can only grow longer but not shorter (since most people are born a little farsighted, which would disappear as the eyes elongate a little in the early stages of life. This is assuming the child is not spending long periods of time doing near work, which would cause the elongation to be of much larger magnitude. Therefore, it is believed that the human eye is equipped with the mechanism to elongate but not to shorten).

 2).The Hormetism theory: People who believe that plus lens therapy works by a Hormetism mechanism believe that plus lens therapy works in the same way as in the "Only Longer" theory, but the difference is that Hormetism theory states that it could use stress (spasm) to change the length of the eye in either direction.

Which theory do you agree with, and why? And can hyperopia (NOT Presbyopia) be acquired (this is a tough question to answer, especially in modern times, when even getting enough time of distance focusing to keep eyeball length short enough to achieve 20/20 is difficult and rare enough). But if hyperopia could be acquired , it means that the eyeball can indeed grow shorter. To hinder confusion, only cases in which hyperopia was acquired when the individual was under the age of 35 would be taken into consideration, because its symptoms are too similar to presbyopia.
« Last Edit: December 22, 2014, 12:58:08 AM by ScientificMind »

Offline OtisBrown

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Re: Can the eye grow shorter?
« Reply #1 on: December 26, 2014, 08:02:01 PM »
Hi ScientificMind,

A good question to ask, is if any optometrist got "out of" -3 diopters?  In other words, is it possible.

http://myopiafree.wordpress.com/od-success/

The optometrist got out of -3 diopters, so I would take her very seriously.

Also, please read Todd's commentary, who got out of about -2 diopters, and it took him six months to do it.

That is the current status, of prevention - if you choose to "do it yourself".




Hello fellow myopes/myopia preventers! I am so happy to have found this community for myopes! I have no doubt that plus lens therapy works. My belief in it is firmly supported by science, logic, and personal experience. I only regret that my parents and I did not know about earlier, which could have prevented my current condition of about -3.25 myopia.


Anyways, I started this topic to form a discussion about the theories of plus lens therapy.
There are two theories that supporters use to explain how plus lens therapy works. I made up the names for these theories myself as summaries, which basically only disagree on if the eye could grow shorter.


1).Only Longer Theory: Some of the pioneers of plus lens therapy such as Donald S. Rehm (author of the Myopia Myth and inventor of the patented myopter) believe in this theory believe that spasms develop in the eye after long periods of near work, and this spasm causes slight degrees of myopia (better than -1D). This theory states that plus lens can ELIMINATE MYOPIA ONLY WHEN THE EYES ARE AT THIS STAGE. When the spasm is allowed to continue or intensify through further near work, the spasm then causes the eyes to grow longer, in attempt to cause future near work to not cause the eyes to spasm. This theory thinks that myopia CANNOT be eliminated at this stage, because the eye can only grow longer but not shorter (since most people are born a little farsighted, which would disappear as the eyes elongate a little in the early stages of life. This is assuming the child is not spending long periods of time doing near work, which would cause the elongation to be of much larger magnitude. Therefore, it is believed that the human eye is equipped with the mechanism to elongate but not to shorten).

 2).The Hormetism theory: People who believe that plus lens therapy works by a Hormetism mechanism believe that plus lens therapy works in the same way as in the "Only Longer" theory, but the difference is that Hormetism theory states that it could use stress (spasm) to change the length of the eye in either direction.

Which theory do you agree with, and why? And can hyperopia (NOT Presbyopia) be acquired (this is a tough question to answer, especially in modern times, when even getting enough time of distance focusing to keep eyeball length short enough to achieve 20/20 is difficult and rare enough). But if hyperopia could be acquired , it means that the eyeball can indeed grow shorter. To hinder confusion, only cases in which hyperopia was acquired when the individual was under the age of 35 would be taken into consideration, because its symptoms are too similar to presbyopia.

Offline OtisBrown

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Re: Can the eye grow shorter?
« Reply #2 on: December 27, 2014, 06:35:49 PM »
Hi Scientific Mind,

A great deal of understanding, comes from asking the right questions.  In science, you ask the question, is the eye dynamic, when objectively tested.

In other words, the word, "cure" does not exist, in science.

http://myopiafree.i-see.org/FundEye.html

In medicine, they ask, how can we satisfy the general public, in an "instant" way, while denying the above scientific truth.

Based, on the "pure science" picture of all natural eyes, I SUGGEST, that it would be very wise, to start wearing a preventive plus, when
you begin having difficulties reading the the 20/40 line.

The OD will tell you that the proven objective picture, of the natural eye, is pure nonsense, and you should wear the -2.0 to -1.5 diopter the
OD will prescribe for you child.

When you ask, should I urge my child to NOT WEAR that -2 diopter, the OD will tell you that there is NO SCIENTIFIC PROOF, that a minus lens has ANY EFFECT ON THEY EYE'S REFRACTION.

This does create a profound distrust in the optometrist, and his sweeping statement, about even the safety of the minus lens.
« Last Edit: December 29, 2014, 09:16:22 PM by OtisBrown »

Offline Todd Becker

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Re: Can the eye grow shorter?
« Reply #3 on: December 29, 2014, 08:21:35 PM »
Hi ScientificMind,

Indeed this is a fundamental question:  Can the eye grow shorter?  The evidence is quite compelling that it can, from both animal and human studies, listed below. References 4 and 5 in particular include convincing measurements showing how the axial length of the eye decreases in response to wearing plus lenses:

1. Hung, L.F., et al. (1995) Spectacle lenses alter eye growth and the refractive status of young monkeys. Nature Medicine, (1) 761-765

2. Irving et al, (1991) Inducing myopia, hyperopia and astigmatism in chicks. Opt. Vis. Sci. 68: 365-368.
http://www.ncbi.nlm.nih.gov/pubmed/1852398

3. Irving et al. (1992). Refractive plasticity of the developing chick eye. Opthal. Physiol. Opt. 12, 448-456.
http://onlinelibrary.wiley.com/doi/10.1111/j.1475-1313.1992.tb00315.x/abstract

4. Howlett and McFadden (2008). Spectacle lens compensation in the pigmented guinea pig
http://www.sciencedirect.com/science/article/pii/S0042698908005129

5. Read, Scott A. et al. (2010) Human optical axial length and defocus. IOVS, 51 (12) 6262-6269
http://www.iovs.org/content/51/12/6262.long

6. Hung, G.K., Ciuffreda, K.J. (2003). An incremental retinal-defocus theory of the development of myopia. Comm. Theor. Biol. 8: 511-513
http://visp.rutgers.edu/IRDT%20of%20Myopia%20Development.pdf


Also, just to clarify, the Hormetism method is based on the Incremental Retinal-Defocus Theory of myopia and hyperopia, described in Reference 6 above.  The IRDT framework holds that the stimulus for axial lengthening or shortening is incremental defocus, not any sort of "spasm", as indicated by your statement above.  Incremental defocus is detected by the eye by means of an increase or decrease in the blur area of the image projected upon the retina.  This in turn induces a cascade of neuromodulators that modify the rate of proteoglycan synthesis, ultimately controlling the eye's differential rate of growth in the axial direction.

This is not just an idle theory -- it has experimental verification in a variety of animals and humans.

Todd







« Last Edit: December 29, 2014, 08:41:43 PM by Todd Becker »

Offline Todd Becker

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Re: Can the eye grow shorter?
« Reply #4 on: December 29, 2014, 08:40:14 PM »
Myopia rehabilitation is an experimental field at best. So far, none of the people who claimed recovery or improvement have posted detailed measurements of axial length (AL), corneal curvature and/or lens refraction, verified by optical equipment before and after their efforts. Thus, you should take such claims with a grain of salt.

Jimboston,

As you and I have discussed elsewhere, I could of course get myself refracted, but I'm not sure what good this would do, for several reasons:

A. I did not get myself refracted before using incremental defocus methods to work myself out of myopia, so I have no "baseline" for comparison.  So if I report an axial length now, you will find it to be persuasive only if you have an earlier measurement with which to compare it.  But I can't go back in time to get that number.  So a single measurement now is meaningless. 

B. Axial shortening of the eye in response to the applied defocus of plus lens has already been demonstrated in numerous animal and human studies (cited in my above response to ScientificMind).  These were controlled studies using statistics on sample populations.  Far more convincing that my single anecdotal example, I would think.

Now I'll grant there are some questions that have not been studied, which would providing additional support for the practicality of the plus lens method:

Q1. How do the benefits of selective use of plus lenses ONLY at the edge of focus compare with passively wearing plus lenses for distance or all the time?
Q2. How is the effectiveness of the plus lens method affected by age, health, diet, and genetics?  Can everyone benefit, or only the young, healthy and genetically favored?

Those last two questions are worth answering.  But to answer them conclusively will require more than anecdotal reports.  They will require new studies.  That won't happen without first convincing researchers organize and funding the studies.  We're not there yet.

So for now, all we have to go on are the general mechanistic studies already reported, general physiological knowledge, and the accumulated experience of people like myself and the dozens who have reported progress on this site.

Perhaps some of you who read this and have not yet started the method would like to have your eyes refracted before and after your print pushing work, and you could report the data back here.

Todd

« Last Edit: December 29, 2014, 08:45:59 PM by Todd Becker »

Offline HansK

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Re: Can the eye grow shorter?
« Reply #5 on: December 30, 2014, 05:12:35 AM »
Jimboston,

As you and I have discussed elsewhere, I could of course get myself refracted [...]

Hi Todd,

it would be interesting to know if your far point is infinity (no nearsightedness) or if you still have (a slight amount) myopia which is not significant (anymore) because you can see 20/20. As for me, with my undercorrected contact lenses for distance activities (-1.0, my full-prescription would be -1.5), I can see 20/16 (in Germany, they use decimal values: 1,2) and almost 1,5 (about 20/13).

The OD was surprised that I could almost read the 1,5-line (20/13) because he said "normal people cannot see that" and my mother said "I can easily read this". So she did - she does not need glasses, but she is getting presbyopia - and she easily read 20/10!

And I wonder how "fast" the eye responses because since 2 months, I am working on my eye sight and unfortunately, nothing happened (except of "flashes" which I do not have anymore). Can you share your experiences cutting your prescription (rate of improvement)?

That would be great to know approximately what we can expect.

Kind regards,
Hans
« Last Edit: December 30, 2014, 05:18:52 AM by HansK »

Offline gekonus

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Re: Can the eye grow shorter?
« Reply #6 on: December 30, 2014, 06:23:22 AM »
How long have you been using the plus?

Yeah I do get many clear flashes btw.. so definately the use of the plus makes more frequent flashes

Offline CapitalPrince

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Re: Can the eye grow shorter?
« Reply #7 on: December 30, 2014, 12:06:43 PM »
its been so long i forgot about this forum.

yes the eye can get shorter. i know a few people who are very farsighted +6D or more. Particular a boy who is 8 years old and about +10D  Obviously none of these people are born that farsighted. They are probably born +1D to +3D and then at young age they went to see an (somewhat greedy, unethical, or plain boneheaded) optometrist who gave them a strong plus when they don't need it, resulting in very very hyperopic vision.

so this shows through some type of defocus the eye can move in the positive direction (the possibility is there). so its logical to assume that reading at the blur point (with or without a plus) for sustained period of time will cause the eyes to get shorter.

Offline Alex_Myopic

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Re: Can the eye grow shorter?
« Reply #8 on: December 30, 2014, 02:19:09 PM »
Well, from what we know from DeAngelis, Becker and Frauenfeld, passive focus doesn't work

DeAngelis suggests a mild plus for about an hour when at home. I have done it and I'm not sure about te results. I have restarted it as a mild shock in order to break my plateau.

Offline OtisBrown

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Re: Can the eye grow shorter?
« Reply #9 on: December 31, 2014, 06:56:24 AM »
Subject:  There is hard SCIENTIFIC data, that does show that the fundamental eye does change in a positive direction, from wearing a plus lens.  (Boston, calls this natural process, "hyperopization".

Otis>  I also do not mean this as a personal attack on Jim Boston.  I just want to get the objective scientific fact straight, that do show that  the  natural eye is RESPONSIVE to the correctly worn plus lens.

Boston> " Todd, no part of my comment was intended as a personal attack;

 it's all just a matter of fact: no one has yet shown hard data on the phenomenon of "hyperopization".


Otis> First, the concept that the eye will change its refractive STATE, when a plus is placed on it is proven as pure science.

https://www.ocf.berkeley.edu/~wildsoet/images/pos_lens_induce_hyperopia.swf

Otis> Then, of course the objective FACTS that confirm this dynamic behavior of the natural eye.  Not only is the natural eye dynamic, but it will change IN BOTH DIRECTIONS:

http://myopiafree.i-see.org/FundEye.html

Otis> We can have a lot of pleasant discussions, about the behavior of the fundamental eye, as pure science, and about hard facts. The important issue is to ask the right questions.  The image of the eye as dynamic, with final objective proof, is the real issue to be understood.

Otis> But please do not tell us that there are no hard facts, when it comes to science and the behavior of all natural primate eyes.

Otis> I think we need a scientific review of all science, not one person, telling us that there are not hard scientific facts about the eye's responsiveness to a plus or minus lens.
« Last Edit: January 02, 2015, 04:49:39 AM by OtisBrown »

Offline CapitalPrince

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Re: Can the eye grow shorter?
« Reply #10 on: January 07, 2015, 09:22:08 PM »
Interestingly this is Steve Leung position from an email he sent. http://chinamyopia.org/internetfriend/usahussain03.12.13.htm

"Once the elongation of the axial length has ocurred, there is no means to shorten it other than banding surgery on the surface of cornea for the purpose to reduce amount of myopia."

I would have expected Dr. Leung to say something different.

Offline Bloobi

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Re: Can the eye grow shorter?
« Reply #11 on: January 24, 2015, 11:31:54 AM »
Quote
Perhaps some of you who read this and have not yet started the method would like to have your eyes refracted before and after your print pushing work, and you could report the data back here.

Todd

Hi all,
I am new here but already busy with vision improvement since the end of November 2014. I plan to have my eyes measured in some weeks where both the axial length of the eye is measured and a cornea map is determined. I will post the results here. Current progress is one diopter since I started two months ago. My initial values were OD -6.75 and OS -8.00 without significant astigmatism. Improvement back to 0 diopter would be the equivalent of axial shortening of 2 to 3 mm, so that should be measurable without doubt, even when taking into account the inherent measurement error of the refractor used. I will also ask to make a corneal map with the measurement of optical strength on different locations of the cornea to see if progress may be due to changes in the curvature of the cornea.

I am quite fanatic with vision training with a constant under-correction of about -0.5 and having a total of 4 different plus glasses at my disposal for different in-door tasks like reading, working at the computer, cooking etc. My goal is to have an almost constant situation of small defocus to trigger the processes Todd mentioned.

Offline j23

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Re: Can the eye grow shorter?
« Reply #12 on: November 10, 2016, 02:30:45 AM »
its been so long i forgot about this forum.

yes the eye can get shorter. i know a few people who are very farsighted +6D or more. Particular a boy who is 8 years old and about +10D  Obviously none of these people are born that farsighted. They are probably born +1D to +3D and then at young age they went to see an (somewhat greedy, unethical, or plain boneheaded) optometrist who gave them a strong plus when they don't need it, resulting in very very hyperopic vision.

so this shows through some type of defocus the eye can move in the positive direction (the possibility is there). so its logical to assume that reading at the blur point (with or without a plus) for sustained period of time will cause the eyes to get shorter.

The example about a young boy may be not that easy to explain with "eye got shorter".
At the same time eye grows in axial length, the lens and cornea are flattening (I guess of a bit growing), thus the lens are flatter, comparing to eye not lenthening enough you can grow refraction error of +10D even if you had +3D when born.

The rule is 1mm axial length is around +3D difference.

you can look at statistics year by year - child eye length
newborn - 17mm
3 year old - 20mm
http://www.okulistyka.com.pl/_klinikaoczna/index.php?strona=artykul&wydanie=41&artykul=710

So everything counts: https://en.wikipedia.org/wiki/Dioptre
"cornea accounts for approximately two-thirds of this refractive power (about 40 dioptres) and the crystalline lens contributes the remaining one-third (about 20 dioptres)."

There is a reason why glasses are prescribed for farsighted children - there is a belief and knowledge that eye muscles are too strained which can lead to different diseases if not corrected (not full but properly under-correct, so eye can still grow maybe a bit slower ). Of course one can relieve a child with natural method (look far to get more rest of accomodation) - but sometimes even this is not enough "in nowadays lifestyle".

« Last Edit: November 10, 2016, 04:11:38 AM by j23 »

Offline j23

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Re: Can the eye grow shorter?
« Reply #13 on: November 23, 2016, 02:07:49 AM »
I have a doubt about PLUS
Could anybody help on this ?

What is the answer for axial length of 50+ seniors ? They take stronger and stronger plus not for any prevention but for presyobia.
Then by using such plus (+1 , +2 or even more) they should acquire pretty quickly hyperopia ?

So are they too old to grow the eye shorter (less elastic) ? Or they do not properly wear PLUS (not to the limits which triggers change).

 

Offline OtisBrown

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Re: Can the eye grow shorter?
« Reply #14 on: November 24, 2016, 12:01:30 PM »
I have a doubt about PLUS
Could anybody help on this ?

What is the answer for axial length of 50+ seniors ? They take stronger and stronger plus not for any prevention but for presyobia.
Then by using such plus (+1 , +2 or even more) they should acquire pretty quickly hyperopia ?

So are they too old to grow the eye shorter (less elastic) ? Or they do not properly wear PLUS (not to the limits which triggers change).

Hi J23

1) No one measures a "length". That is a myth.  Do not get caught in that error of thinking.  People objectively measure a refractive STATE - only.

2) Are you 50+ years.  You are not?  Why do you bother with a hypothetical question?

3) I wear a plus for prevention.  My distant vision is in the range of 20/20 to 20/15, self checked.  My refractive STATE is in the range of +1/2 to +3/4 diopters. That is NECESSARY for very clear distant vision.

4) I have no problems with my refractive state.  I do not see why you would have a problem.