Author Topic: Video and slides from my talk on myopia at the Ancestral Health Symposium  (Read 10037 times)

Offline Todd Becker

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« Last Edit: August 12, 2014, 08:15:00 AM by Todd Becker »

Offline Arachne

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Hi Todd,

Those slides are an excellent and useful summary of what we know about myopia and how to reverse it. It is hard to describe a somewhat difficult (not to say controversial) concept in a succinct and convincing way, and you have achieved that. I hope your talk was well received. Many thanks for the link to my blog in the References, by the way! :)

Offline ZC

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Todd,

Great job! I no of no other resource that explains our current knowledge of myopia rehabilitation so lucidly and completely. Thanks.

I see others are posting youtube videos of their presentations at the AHS. Will you be doing that?

Offline Todd Becker

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Offline Todd Becker

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There is a risk that complete beginners deem plus lenses The Holy Grail of therapy, which by now most advanced practitioners understand are not enough, and maybe even irrelevant to improvement except for setting up the right working distance. I hope in future talks you put emphasis on the cognitive (attentional) aspect of focusing, which probably is much more important than waiting for vision to improve by passively/mindlessly pushing print with plus lenses. I know you are well aware of that, but without explicit pointers, beginners can easily get the wrong idea that it's the distance/defocus that leads to improvement instead of working consciously to clear up the blur -- I made this mistake myself.

Did you recommend to the audience to only push/pull the observed text or did you want them to also carefully pay attention to the text features so they could consciously resolve the blur?

Hi Jim,

My talk was intended as a basic introduction -- for rank beginners -- so I necessarily left out a lot of the finer points.   Your point is a fair one -- which I agree with -- that plus lenses cannot be used passively. You can't just put them on and expect magic. 

Actually I don't see plus lenses as fundamental to active focusing. they are just one of many tools.  The basic technique is working your eyes to resolve incremental defocus.  As the talk makes clear, the specific technique to be used depends on your degree of myopia and whether you are looking near or far.  Plus lenses are useful only for those with mild myopia (less than about -2.0D) for use for relatively near work.  Those with strong myopia can practice print pushing and active focusing without lenses.  And for distance, other methods are suggested.

To my mind, attention and intentionality are inherent to what it means to read or observe objects "at the edge of focus" --  wheether in print pushing or distance viewing. At the 22 minute mark in the video, I described the technique of "fusing ghosted images", using the illustration of overhead telephone wires.  It's fun and playful example of active focusing -- concentrating on the darker of two images and allowing it's ghost to fade away.  Again, this inherently involves intentionality, attention and cognitive selection.  And again, at 29:45  minutes into the talk,  I discussed stimulating your eyes by making active distance viewing into a game -- tracing branches, shadows and details.

I suppose I don't understand how one could practice print pushing or distance focusing in anything but an active way. However, perhaps you are right that this is not just a finer point (no pun intended) or enhancement, but rather a key feature of the technique -- one that bears emphasis even to beginners.  The fact that it helped you suggests that it could help many or most who are embarking on this journey. 

I will definitely include more explicitly the attentional or cognitive  this in future presentation.  I think it will strengthen and clarify the concept of active focusing.  Thanks for the suggestion!

2. What's new to me -- and I guess everyone on the forums -- is your recommendation of doing print pushing for 2-4 hours. If by this you mean actively paying attention to text features for such a long period of time, most people simply won't have the mental capacity to do it. So just to clarify:

- would you agree that the 2-4 hours of print pushing should be cumulative (a sum of all the small sessions you do throughout the entire day)?
- is 2h an arbitrarily set minimum threshold for achieving improvement?

I'm pretty sure I've previously suggested -- on this forum and in previous interviews  -- working at print pushing for several hours per day, with frequent breaks every 15-30 minutes.  Rest is important, and I've been careful to advise taking a break if you feel strain or redness.  Overtaining is counterproductive.

People want specific recommendations. The guideline of 2-4 hours is not based on rigorous experimentation, but reflects both my personal experience and what I've gleaned from others who've shared their experience regarding what has been effective.  Yet individuals vary widely in what is effective and tolerable, so this is only crude estimate.  Some may find 2 hours to be excessive or tiring, while others may need or find benefit from more extended sessions.   I think 2-4 hours daily is good place to start, building in frequent breaks.

However, in future presentations, I can certainly do more to point to emphasize YMMV and the need to experimentally adapt the method to one's individual circumstances.

I'd be interested to know what type of frequency and duration have worked for you, Jim.  And others feel free to chime in here too.

Thanks again for the good comments, Jim.

Todd

Offline OtisBrown

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Hi Todd,

I will add my own (biased) commentary.  I have been told, almost with no "break", by medical people that ANY prevention, even the slightest is totally impossible, and impossible, because science says it is impossible.

This is the absolute of a man trained to quick-fix with a strong minus lens - always.  I say, and agree that it take a very strong man to make the intellectual and physical commitments to wearing a plus - to be successful with it.  It always will take a long-tern process to achieve final success - as you have done it.

I am never your critic.  I think that each person must develop is "own theory", as he works to clear his own Snellen from 20/60 to 20/20.  As you know, I never say, "cure" because I consider that is "medical", and getting the required change must be self-measured, and therefore is not medical.

Personally, I only ask a person to do something that I consider possible an reasonable.  That is why I restrict my statements to self-verified 20/60 (and perhaps -2 diopters).  I consider ANY WEARING of a minus - to be destructive of vision - and with rare exceptions - permanently.

As you know, I believe that any true solution, must be a wise parent, helping his own children.  This means talking to them and explaining the absolute necessity of monitoring your own Snellen (and refractive state if technical), and never allowing your visual acuity to go below 20/40 - on your own.

I know most children will fight against wearing of a plus, when at that delicate stage.  Yet that is where the battle must be fought.

If the child "fights against" plus prevention at 20/40, he most certainly will lose more, and more of his distant vision though 6 years of school.

He should not be in ignorance of that truth.  If he ignores the wearing of the plus - his loss of vision will be his own fault - in my candid judgment.

But as always, I deeply appreciate your successful effort - and hope you will continue.  You have the right answer for yourself - and hope other people (at 20/60) will follow your skilled leadership with this truly difficult problem.

This is a solution - that can never be made into a "medical solution."


ZC -- my video is now posted!

http://gettingstronger.org/2014/08/myopia-a-modern-yet-reversible-disease/
« Last Edit: August 15, 2014, 04:34:26 PM by OtisBrown »

Offline Todd Becker

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I suppose I don't understand how one could practice print pushing or distance focusing in anything but an active way.

The answer is blur adaptation: learning to see the whole blob & accepting it. Once a myope lives deep into the blur zone (~-0.75D and worse) for years, and especially if he does a lot of near work that locks the focusing range, at some point the eyes give up focusing and one learns to live with the blur. Some strong myopes go without glasses from time to time and have become accustomed to extraordinary amounts of blur (e.g. -4D, -5D). This is dangerous. The problem is once you tolerate a lot of blur & teach the eyes not to make any effort, putting on plus lenses or working at the edge of blur provides zero stimulus to you. Unlike young chicks & monkeys who quickly respond to retinal defocus, myopic human eyes can become very resistant to change. My fear is that a lot of long-term myopes, like myself, are resistant to defocus itself due to prior acclimation to unresolved blur, and instructing them to put on plus lenses or reduce prescriptions might give them false hope, because without the cognitive component the eyes will simply never make the effort on their own.

Well, this is certainly a revelation to me.  I suppose I completely discounted the possibility that anyone would willingly tolerate and adapt to "living with the blur".  You suggest that young chicks and monkeys respond to retinal defocus by adaptation, while human myopes resist this.  Do you suppose this a species difference or rather a matter of aging or psychology?

If the myope eye essentially "gives up trying", I would then ask whether it is because the blur is too strong.  I'd think there is some distance at which the myopic eye would make the attempt to focus.  Autofocus cameras employ an algorithm that attempts to resolve a modest degree of defocus by latching onto features that are slightly out of focus and randomly changing focal length; if the focal resolution improves they continue until feature dimensions are minimized; if not, they reverse direction.  I imagine that the eye and brain achieve something similar using biological "algorithms".   

So my suggestion to the myope who has surrendered and decided to "live in the blur" is to find some distance, however close, at which crisp focus is achieved, then to move ever so slightly back beyond the "edge of focus" or far point, and thus to stimulate the eye to adapt.  This is a subtle point that many may miss:  Going even slightly beyond the blur point may cause the eye to "give up".  But I find it hard to believe that the myopic eye exists either in a state of perfect focus OR surrender.  There must be some incremental degree of defocus, however small, that provides a stimulus to adaptive change.

The best analogy I have for this is muscle hypertrophy in response to lifting weights.  There is a degree of overloading which will stimulate a damage-and-repair response.  Exceed that loading and the muscle gives up.  Fall short of that loading and the muscle is not adequately stimulated towards repair and compensatory growth.

So my hypothesis is that the myope who "lives in the blur" has failed to appreciate the value of working within the physiologically effective window of defocus -- the admittedly narrow threshold between D1 (edge of focus) and D2 (edge of blur).  This myope is living beyond D2.

Quote
I'd be interested to know what type of frequency and duration have worked for you, Jim.  And others feel free to chime in here too.

I can trigger 5-20% better VA with each eye within minutes of concentrating. Sadly, I am yet to determine how exactly to persist the changes and how long it takes for them to stick. Locking in the improvements seems to be the most challenging aspect of rehabilitation -- I'm eagerly awaiting Tom to release data from his experiments as these would be core to our theory.

Warning: Like many other frustrated users of PVS, I wasted a lot of time hoping retinal defocus adaptation would work its magic -- it didn't. I'm sad to say that past a certain point, the eyes simply adapt to the blur, and putting them in a state of defocus (mild or strong) is no longer a sufficient stimulus for change. The key most likely lies in the cognitive technique, and that's why I'd like to inform beginners not to pin their hopes on retinal defocus but engaging voluntary focus. Like I previously stated, the distinction should be of great importance.

Thank you for taking my comments into account.

That defocus induces short term changes in the axial length of the human eye has now been proven by Read et al.:
http://www.iovs.org/content/51/12/6262.full.pdf

You raise a key question however, namely whether incremental defocus produces only transient changes in axial length, or whether these changes can be made permanent.  My own view is that repeated, continuous axial length changes add up to sustained, permanent changes.   The best evidence for this position is articulated by Hung and Ciuffreda:
http://visp.rutgers.edu/IRDT%20of%20Myopia%20Development.pdf

Quote
…the theory has been able to explain how repeated cycles of near-work-induced transient myopia leads to repeated periods of decrease in retinal-image defocus, whose cumulative effect over an extended period of time also results in an increase in axial growth that produces permanent myopia.

…Over many cycles, the cumulative result has the effect of a small plus lense being added during the relatively long periods of near viewing…The result of this net-reduced accommodative stimulus is a slightly reduced accommodative response, and thereby a smaller accommodative error is present.

The paper references experimental data to support the theory.


Todd

« Last Edit: August 18, 2014, 11:29:19 PM by Todd Becker »

Offline OtisBrown

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Hi Jim and Todd,

Subject:  Yes, a refractive change of +1 diopter, can take you from 20/60 to 20/30, with wearing of the plus - as you state.

Item: Most people take ANY wearing of a plus to be a serious INTRUSION in their life - that they do not understand.  In that sense - you can never prescribe the insight it will take for longer plus-lens wearing, to make this change more permanent.


Jim>  What is interesting about this experiment is that myopes that were exposed to two hours of +2.5D binocular defocus, achieved 35% improvement in VA, which "was not accompanied by any significant change in the refractive state of the eye", and they improved much more than the emmetropes, who gained 15% on average. The myopic group achieved the equivalent of 1D improvement on acuity tests, and the improvements were maintained for as much as 10 days.

Otis>  I would suggest that a person who makes both his refractive measurement (as I do it), and visual acuity measurement, would convince himself to CONTINUE to wear that +2.5 diopter, and WAIT for expected long-term change in refractive state - that he already proved he achieved in a few days.

Otis> But you never know WHAT a person will do - unless he has the motivation to actually do it.  If he thinks the "plus" is being shoved in his face (as a prescription) he will never wear it - to the extent required.

Otis> If he personally makes these measurements himself, and verifies both  his refractive change, and sees his Snellen passing the normal level - and truly needs excellent vision (a professional pilot), he perhaps will over-come his objection to the plus, and slowly get to "positve status", necessary for naked-eye 20/20 vision. 

Otis> So it CAN BE DONE. But no optometrist can do it for you - you must do it for yourself.


Offline Todd Becker

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Jim,

Good discussion - just the kind of give-and-take that I like on this forum.  Debate helps us to refine our perspectives. You make a strong case for a cognitive or neural component of visual acuity.  However, I tend to agree with this Wikipedia article that visual acuity has both a refractive and a cognitive component.  As important as the cognitive component may be, we cannot ignore or minimize the refractive component:

http://en.wikipedia.org/wiki/Visual_acuity

I'd like to address some of the points in your post:

I think the entire rehab community has become more or less obsessed with axial length, even though not ONE person who has improved has published such objective measurements on the Internet. Naturally, myopes are interested in better perception, not better eyeball shape…
...For starters, there is a daily fluctuation of about 25 microns:
…In comparison, the myopic defocus study by Read et al. achieved 14 microns in axial length shortening after 1h of +3D defocus.[/i]
...the myopic eye is especially susceptible to high accommodative stimulus and can temporality elongate by as much as 58 microns![/i] I.e. the effects of defocus are totally overshadowed by simply shifting the focal point
...Monocular myopic defocus and daily changes in axial length and choroidal thickness of human eyes[/i]) occluded subjects with +1.5D defocus for an entire day. They found that axial length shortening peaked at 14 microns, but the effect was almost entirely erased after sleep.
….In any case, how much of an axial length change is sufficient to induce a noticeable change in visual acuity is unknown. All of these studies state that there wasn't a measurable difference in refraction after defocus, and the 2012 study shows how temporary the effects are. Maybe prolonged defocus for many months could be the solution, but such experiments are highly unlikely.

I think the point of the study by Read et al. was to show that changes in axial length can be initiated in the predicted direction within a very short time.  But nobody is arguing that a tiny change of 14 or 25 or 58 microns results in appreciable myopia.  That represents only about 0.1% change in the length of the eye, assuming a 25 mm long eye!

By contrast, Achison et al found that the average axial length of myope is about 350 microns (0.35 mm) longer per diopter than that of emmetropes. 

http://www.iovs.org/content/45/10/3380.full

So someone with mild myopia of -3D would have an eye that is about a full millimeter (1000 microns) longer than someone with normal vision.  Thats an increase of about 4% relative to a normal eye length of 25 mm.  That's enough to produce real refractive effects, which I would argue constitute true axial myopia.

The Incremental Retinal Defocus Theory of Hung and Ciuffreda contents that true and permanent axial myopia results from the cumulative effect of thousands of cycles of defocus-induced axial lengthening, consolidated by sustained and repeated stimulus to scleral tissue growth.

You raise a good point that nobody who has reversed their myopia has posted measurements of their eye's axial length change on the Internet.  Fair enough, but if Achison is right that emmetropoes have eyes that are typically a millimeter or more shorter than that of myopes, I would find it surprising that this would be true of "virgin" emmetropes who were never myopic, and yet not of emmetropes who are former myopes.

I urge you to review the following study on the effects of neural adaptation on VA:[/b]

http://journals.lww.com/optvissci/Abstract/2004/07000/Blur_Adaptation_and_Myopia.16.aspx

…the introduction of convex fogging lenses produced significantly greater reduction in both VA and contrast sensitivity in emmetropes when compared with myopes.
...fully corrected myopes had significantly higher blur thresholds than did emmetropes[/b][/i]; i.e., corrected myopes were less efficient at first detecting the presence of dioptric blur.

What is interesting about this experiment is that myopes that were exposed to two hours of +2.5D binocular defocus, achieved 35% improvement in VA, which "was not accompanied by any significant change in the refractive state of the eye", and they improved much more than the emmetropes, who gained 15% on average. The myopic group achieved the equivalent of 1D improvement on acuity tests, and the improvements were maintained for as much as 10 days.
The implications are great:

1. Myopes might have a very high blur threshold and respond better to higher levels of blur than emmetropes.
2. Neural adaptation can have a considerably more noticeable & lasting effect on VA than axial length and other structural changes.

The "blur adaptation" effect is interesting, as is the ability to achieve improvements in visual acuity using plus lenses.  But these effects appear to be limited in degree and may be transient, as the study acknowledges.  Given the short exposure of only 2 hours, I'm not surprised the acuity effects were not "accompanied by any significant change in the refractive state of the eye", for the reasons I cited above. 

Again, this is not to discount or minimize the significance or value of cognitive or visual acuity improvements in vision.  But I would argue that myopia is a refractive error that goes well beyond visual acuity.

…I am trying to shift awareness towards the cognitive aspect of rehabilitation and away from the fixation on structural and optical aspects of vision.[/b][/i] This is the only way we can explain such rapid changes in perception and why most people who do eye exercises and/or wear plus lenses don't improve or hit plateaus for years. Even DeAngelis himself stated that it took him 10 years to recover from -2D, which is contrasted by your recovery, which only took a year. Maybe, our intuition of the shape of the eye & the role extra ocular muscles is misleading.

The existence of plateaus is a real problem.  But I don't see how it pertains to whether myopia is primarily refractive or cognitive.


Quote from: todd
So my hypothesis is that the myope who "lives in the blur" has failed to appreciate the value of working within the physiologically effective window of defocus -- the admittedly narrow threshold between D1 (edge of focus) and D2 (edge of blur).  This myope is living beyond D2.

I am very hopeful you're right. Maybe there is a correct distance at which automatic algorithms are triggered, but the problem with this view is that it doesn't explain why people who are constantly working at the edge of blur hit plateaus. Take me for example: I've been doing computer work at the edge of blur for many years, but I've grown completely accustomed to slight blur, because it doesn't impede my completion of a task. In other words, it doesn't bother me mentally in a way that forces me to constantly try and make the slight blur perfectly in focus. I've adapted mentally, but not physiologically.

Perhaps you are right…that you ave become accustomed to the blur, even attempting to work at the edge of focus.  But the study you cited above by Sini George found that myopes wearing +2.5D plus lenses for two hours achieved 35% improvement in visual acuity, "equivalent" to a 1D improvement.   Presumably those subjects wearing the plus lenses were "pushing" their eyes closer to the the edge of focus.  So then why did it help them, whereas print pushing left you at a plateau?   Or is the conclusion that both you and the subjects in the study achieved some improvements in visual acuity, but that defocus by whatever means can only improve visual acuity to a small degree…leaving you at a plateau?

While many people plateau (as did I for weeks or months at a time along my journey), many of us find that we eventually break through the plateau and myopia decreases the the point we no longer need glasses.  I'm not the only one…this site is full of several others who have achieved 20/20 or better, having started with significant myopia.   I think that plateaus are just part of the way that humans change.  (See my post How to break through a plateau)

I'm not sure I know why it is easier for some of us than others to reverse myopia.  Age, diet and genetics may affect the ease of rehabilitation. But the evidence so far tells me that myopia reduction involves more than a cognitive change -- that the reduction in myopia is accompanied by real reduction in refractive errors, stemming both from relaxation of the pseduomyopic lens, and a decrease in axial length of the eye.

Todd
« Last Edit: August 20, 2014, 09:54:32 PM by Todd Becker »

Offline ZC

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There really is no substitute for real data.

"Dr. Alex" claims here:

http://frauenfeldclinic.com/axial-elongation-of-the-eyeball-facts-fiction/

that he has "seen many hundreds of cases well into the high 5 diopter range, without any axial elongation.  Likewise, you could be at -8 diopters, and have no more than a single millimeter of axial elongation (for reference, your eyeball is about 25mm long)."

The problem is that he appears to hold contradictory positions.

First, based on the quotation above, it might be the case that he has seen thousands of cases of less than 6D that DO have axial elongation. Until we see the complete set of data, it is hard to draw reliable conclusions.


Second, elsewhere (in his "Four Pillars":

http://frauenfeldclinic.com/the-frauenfeld-method-vision-rehabilitation/

he proposes a two-step causal process for, essentially, all myopes who wear glasses. The first stage is ciliary tension and the second stage is axial elongation. The implication is that everyone has AL if they are wearing minus glasses.

When confronted with these apparently contradictory positions, he responded here:

http://frauenfeldclinic.com/myopia-forums/topic/confused-about-blog-post-axial-elongation/


His response: "It’s usually a mix of both. I am saying that you *can* show no signs of axial elongation up to 6 diopters of correction." So, here he appears to say that the two-stage, "Four Pillars" explanation does not hold universally. By using the word "usually," he seems to be saying that although there are hundreds of myopes with no AL, there are more of them with AL.


I know that we all want clear answers and this post does not provide any. Dr. Alex appears to be the only medically trained person who has many years' experience dealing with hundreds of rehabilitating myopes who is willing to share his experience publicly. (I know that the plural of "anecdote" is not "science," but it still is useful to hear from someone who has knowledge of many data points.)

If we assume that his more recent claims are more accurate than the older ones, we can conclude that there is a significant minority of myopes up to 6D or so who have no AL, as determined by actual measurements.
« Last Edit: August 21, 2014, 05:06:27 AM by ZC »

Offline OtisBrown

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Hi ZC,

Subject: Could you please define exactly what you mean by, "real data".

Item: Who is supposed to  produce, "real data". Further, who is supposed to judge, "real data".  It is a critical scientific question.

Item: This is certainly a question I would ask.


I deeply appreciate Dr. Alex's discussions and efforts.  (But he is doing a "bottoms up" discussion).  There is no OD, in an office, who EVER measures a "length".  It is quite impossible.  He measures a refractive STATE, with a trial-lens kit.  So, I think, inferring a "length" when you are measuring a "refractive state" is a tragic mistake.

The natural eye has the ability to change BOTH its "length", (if you wish that argument), and its total refractive power.  This is for both the "short term", and the long-term.  But no one has been able to separate-out, a "length change," from a "refractive change".

I think people getting into this argument, simply get themselves "wrapped around the axle", and need to think about the fact that the eye is a sophisticated system, that can (very slowly) change its refractive state (and it is not necessary to worry about length).

I suggest that both these change - for both "accommodation" and long-term changes.  That should clear the air.

As always, it is possible to argue about the dynamic behavior of all natural eyes (measured as a refractive state) without being disagreeable.

That will produce intelligent science.


There really is no substitute for real data.

"Dr. Alex" claims here:

http://frauenfeldclinic.com/axial-elongation-of-the-eyeball-facts-fiction/

that he has "seen many hundreds of cases well into the high 5 diopter range, without any axial elongation.  Likewise, you could be at -8 diopters, and have no more than a single millimeter of axial elongation (for reference, your eyeball is about 25mm long)."

The problem is that he appears to hold contradictory positions.

First, based on the quotation above, it might be the case that he has seen thousands of cases of less than 6D that DO have axial elongation. Until we see the complete set of data, it is hard to draw reliable conclusions.


Second, elsewhere (in his "Four Pillars":

http://frauenfeldclinic.com/the-frauenfeld-method-vision-rehabilitation/

he proposes a two-step causal process for, essentially, all myopes who wear glasses. The first stage is ciliary tension and the second stage is axial elongation. The implication is that everyone has AL if they are wearing minus glasses.

When confronted with these apparently contradictory positions, he responded here:

http://frauenfeldclinic.com/myopia-forums/topic/confused-about-blog-post-axial-elongation/


His response: "It’s usually a mix of both. I am saying that you *can* show no signs of axial elongation up to 6 diopters of correction." So, here he appears to say that the two-stage, "Four Pillars" explanation does not hold universally. By using the word "usually," he seems to be saying that although there are hundreds of myopes with no AL, there are more of them with AL.


I know that we all want clear answers and this post does not provide any. Dr. Alex appears to be the only medically trained person who has many years' experience dealing with hundreds of rehabilitating myopes who is willing to share his experience publicly. (I know that the plural of "anecdote" is not "science," but it still is useful to hear from someone who has knowledge of many data points.)

If we assume that his more recent claims are more accurate than the older ones, we can conclude that there is a significant minority of myopes up to 6D or so who have no AL, as determined by actual measurements.
« Last Edit: August 22, 2014, 11:45:58 AM by OtisBrown »

Offline ZC

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Otis,

You answered the question you posed to me. However, I am going to assume that you were not asking the question rhetorically.

In the context of my post, the expression "real data" would mean explaining how axial length is measured, what length qualifies as "elongated", how many myopes at each diopter range had elongation, and how many did not.

Science is a systematic method of acquiring knowledge. The criteria I outline above would be the beginning of a scientific inquiry. It is not outlandish for doctors to publish papers analyzing their patient populations. The way that science works is that the readers of the published papers judge those papers.

In the links I provided Dr. Alex claimed that he stopped measuring the axial length of his patients because the benefits did not justify the costs, because large numbers of myopes had no elongation. This lends support to jimboston's claim that axial elongation is of marginal relevance to myopia. I would find it hard to believe that Dr. Alex, a purported ophthalmologist (an MD, not an OD), stopped measuring the refractive state of those myopes who sought him out to rehabilitate their myopia. How else would he know when to tell those patients it was time to get a weaker prescription?

If Dr. Alex has retained medical records of his practice (and, conceivably, his father's practice), a systematic analysis of those records would be invaluable to those of us seeking to rehabilitate our myopia. For those of us with higher myopia, it might help us to find out what the chances are of halving our prescription, not needing any prescription, etc. It might help us find out if the probability of successful rehabilitation depends on age, other medical conditions (diabetes?), diet, BMI, etc.

For those of us interested in myopia rehabilitation there are at least three sources of information. There are accounts of personal experiences, like Todd's, David De Angelis's, and others. There are peer-reviewed journal articles. And then there are the medical records of those who have undergone myopia rehabilitation supervised by doctors.

The problem with personal accounts is obvious. We don't know how many people attempted rehabilitation and failed. The problem with the peer-reviewed articles is that no one seems to be able to get funding to do a controlled study that tracks a large number of myopes over  many years.

The medical records of a behavioral ophthalmologist who has treated many hundreds of patients over a period of decades would be invaluable. No, it would not be perfect. There could be survivorship bias as well as all kinds of biases that can distort the reports of both the doctor and the patients. But if the numbers and the procedures were published, the scientific community could then decide how much of a problem these possible biases are.

It is unfortunate that there is an entire medical profession of people who rehabilitate myopes, yet those professionals are quite reluctant to publish what they know. Those who have the most experience and knowledge are, apparently, fearful of having their licenses revoked, so they operate more or less in the shadows. That leaves the public discussion open mostly to amateurs and quacks. Real data would be a first step toward getting the discussion on a less speculative footing.

Offline OtisBrown

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Hi Jim,

Subject: Who defines, "real data" concerning 1) All natural eyes - that can be measured, and 2) Medical studies that start by excluding all real-data (because the medical person never looks at real scientific data)?

Item:  I think you have done and excellent write-up of these issues of measurement.  Your statement should have a separate thread - since the issue you raise are very important - for anyone seeking to avoid entry into nearsightedness, or get out of 20/60 vision.  I would listen to a statement by an OD about plus-prevention to start this discussion.

https://www.youtube.com/watch?v=65vrKTJTyDY

Otis> So ... is the plus effective, providing it is taken SERIOUSLY by a person who self-measures at 20/50.  It is rather obvious that no one is going to run around and, "nag" a child to put on a plus - when doing close work.  That is something that Benny does not consider to be his responsibility.  For that reason, I consider it *my* responsibility to always check my own Snellen, and always exceed the 20/40 line - for starters.  No OD can truly help me with prevention - I must do it myself.

Jim>  It is unfortunate that there is an entire medical profession of people who rehabilitate myopes, yet those professionals are quite reluctant to publish what they know.

Otis> I agree.  A few ODs have recognized that is necessary for their own children to begin wearing a plus, before the child goes below 20/60.  That works on an personal level, and real-science shows why they are successful.  But almost all ODs have been taught (from the first day) that any prevention will always be impossible - so they will never say anything about it.  They assume you want to be "quick-fixed" with a minus, and will  not say that the minus is a truly a, "bad idea".

Jim>  Those who have the most experience and knowledge are, apparently, fearful of having their licenses revoked, so they operate more or less in the shadows.

Otis>  All ODs fear a mal-practice suite, or charge.  That is why you will not find any OD who will volunteer any information. There profession is not helping you get out of 20/60 vision - that is your job.  There job (in their minds) is to make your vision extremely sharp - giving you 20/15 and 20/13 vision - in a few minutes.  That is why I recommend that a motivated person get his own minus lens - and make that measurement himself.  That way, he is more intellectually, and physically responsible to objectively verify his own results.

Jim>  That leaves the public discussion open mostly to amateurs and quacks.

Otis> There you condemn any OD or MD, who discusses the possibility of prevention (at 20/60, and -1.5 diopters), as automatically, being a quack. 

Otis> I do not consider self-prevention at 20/60, to be medicine, and I do not consider people with a good grasp of science to be quacks - who restrict themselves to only prevention at 20/60.  This does include Todd Becker.  Is he a quack, or an amateur? Or is he an excellent engineer who figured out how to conduct true-prevention, for himself based on real scientific data.  What ever your opinion, Todd is objectively successful, based on science.

Jim> Real data would be a first step toward getting the discussion on a less speculative footing.

Otis> Again, are you only thinking that ONLY medical people are going to provide you with real-data?  I personally do not see threshold prevention (with a plus) as a medical problem.  I will agree that no one in "medicine" will be of any help to a person who wishes to avoid entry into "negative status" for the natural eyes.

Otis> But the bigger issue  is this.  Are you willing to take personal responsibilty to 1) Look at a Snellen objectively, 2) Assuming 20/60, then wear the plus systematically, and WAIT, 3) Keep on wearing the plus until you begin reading the 20/40 line, objectively, and 3) Continue to wear the plus until you substantially exceed the 20/30 line.  I do not know what you are reading on your Snellen - so I can not answer these issues for you.   Only you can do that.

Best,



Otis,

You answered the question you posed to me. However, I am going to assume that you were not asking the question rhetorically.

In the context of my post, the expression "real data" would mean explaining how axial length is measured, what length qualifies as "elongated", how many myopes at each diopter range had elongation, and how many did not.

Science is a systematic method of acquiring knowledge. The criteria I outline above would be the beginning of a scientific inquiry. It is not outlandish for doctors to publish papers analyzing their patient populations. The way that science works is that the readers of the published papers judge those papers.

In the links I provided Dr. Alex claimed that he stopped measuring the axial length of his patients because the benefits did not justify the costs, because large numbers of myopes had no elongation. This lends support to jimboston's claim that axial elongation is of marginal relevance to myopia. I would find it hard to believe that Dr. Alex, a purported ophthalmologist (an MD, not an OD), stopped measuring the refractive state of those myopes who sought him out to rehabilitate their myopia. How else would he know when to tell those patients it was time to get a weaker prescription?

If Dr. Alex has retained medical records of his practice (and, conceivably, his father's practice), a systematic analysis of those records would be invaluable to those of us seeking to rehabilitate our myopia. For those of us with higher myopia, it might help us to find out what the chances are of halving our prescription, not needing any prescription, etc. It might help us find out if the probability of successful rehabilitation depends on age, other medical conditions (diabetes?), diet, BMI, etc.

For those of us interested in myopia rehabilitation there are at least three sources of information. There are accounts of personal experiences, like Todd's, David De Angelis's, and others. There are peer-reviewed journal articles. And then there are the medical records of those who have undergone myopia rehabilitation supervised by doctors.

The problem with personal accounts is obvious. We don't know how many people attempted rehabilitation and failed. The problem with the peer-reviewed articles is that no one seems to be able to get funding to do a controlled study that tracks a large number of myopes over  many years.

The medical records of a behavioral ophthalmologist who has treated many hundreds of patients over a period of decades would be invaluable. No, it would not be perfect. There could be survivorship bias as well as all kinds of biases that can distort the reports of both the doctor and the patients. But if the numbers and the procedures were published, the scientific community could then decide how much of a problem these possible biases are.

It is unfortunate that there is an entire medical profession of people who rehabilitate myopes, yet those professionals are quite reluctant to publish what they know. Those who have the most experience and knowledge are, apparently, fearful of having their licenses revoked, so they operate more or less in the shadows. That leaves the public discussion open mostly to amateurs and quacks. Real data would be a first step toward getting the discussion on a less speculative footing.
« Last Edit: August 23, 2014, 07:06:44 AM by OtisBrown »

Offline Todd Becker

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"Dr. Alex" claims...that he has "seen many hundreds of cases well into the high 5 diopter range, without any axial elongation.  Likewise, you could be at -8 diopters, and have no more than a single millimeter of axial elongation (for reference, your eyeball is about 25mm long)."

The problem is that he appears to hold contradictory positions.

First, based on the quotation above, it might be the case that he has seen thousands of cases of less than 6D that DO have axial elongation. Until we see the complete set of data, it is hard to draw reliable conclusions.

Second, elsewhere...he proposes a two-step causal process for, essentially, all myopes who wear glasses. The first stage is ciliary tension and the second stage is axial elongation. The implication is that everyone has AL if they are wearing minus glasses.

When confronted with these apparently contradictory positions, he responded:

... "It’s usually a mix of both. I am saying that you *can* show no signs of axial elongation up to 6 diopters of correction." So, here he appears to say that the two-stage, "Four Pillars" explanation does not hold universally. By using the word "usually," he seems to be saying that although there are hundreds of myopes with no AL, there are more of them with AL.

ZC,

I'm not sure there is any contradiction here.  At the end of the day, myopia is a single, unified phenomenon: a refractive defect of the eye, in which distant objects appear blurred because their images are focused in front of the retina, rather than on it.  However, this unitary phenomenon can occur for two different reasons:  (1) pseudo myopia, in which the ciliary muscle fails to relax causing the image to focus in front of the retina; or (2) axial myopia, in which the axis of the eye lengthens to such an extent that the image is focuses in front of the retina.  Either way, you've got myopia.

The two processes -- pseudo myopia and axial myopia -- are independent, but they are not mutually exclusive.  They can occur separately or together. Alex Frauenfeld, David DeAngelis and I all agree that as a biological process, myopia usually develops in two stages.  The first stage is usually pseudo myopia, typically caused by excessive near work.  I agree with Frauenfeld that pseudo myopia can be quite significant -- even as strong as -5D or -6D in his experience.  And that can occur with absolutely no axial myopia.  Hence, Dr. Alex's first statement that many myopes have no axial myopia is quite plausible, particularly if they have not entered into the vicious cycle of ever-stronger prescriptions for minus lenses.

Axial myopia is typically induced by wearing minus lenses.  While minus lenses are intended to "correct" for distance vision, they simultaneously induce hyperopic defocus during close up focusing, wherein the focal point of the images shifts behind the retina.  This induces axial elongation.   Axial elongation can also occur or be accelerated by other factors, e.g. genetics, diet, or disease processes.

It may not be common, but it is at least conceptually possible that one could have axial elongation without myopia, e.g. if the ciiliary muscles and lens are flexible enough to compensate and focus the image farther back.

The usual case of myopia, however, includes ciilary spasm. Generally, myopia comes down to reduced ability of the ciliary muscles to focus.  Axial lengthening doesn't in itself cause myopia, but it makes it much harder to focus on distant objects, particularly if the ciliary muscles are in spasm due to pseudo myopia.  So axial myopia, fueled by the use of minus lenses, merely exacerbates the problem.

Within this framework, I think that Alex Frauenfeld's statements above are consistent with one another, and also with my current understanding of the etiology of myopia.

Todd
« Last Edit: August 23, 2014, 11:53:43 AM by Todd Becker »

Offline OtisBrown

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Hi Todd,

Thanks for your clarification on pseudo-myopia and eye-length. 

We agree with the result, and perhaps our analysis might be slightly different - which is "normal science and engineering" in my world.

My opinion, is that "initial myopia" is best prevented, in the pseudo-myopia stage (when you can still read the 20/60 line, and self-check your refraction at -1.25 diopters.) Then the issue is this - ".... am I going to take the plus seriously - or am I going to reject it..."  I think that most people will reject the idea - because they do not understand the concept.

The effect of a properly-worn plus (for near, for long-term wear), is that the accommodation system (pseudo-myopia) responds first.  This can result in a change of refraction of +1/2 to +3/4 diopters in about two months.   At that point the person can objectively read the 20/30 line, and PASS all required DMV tests.   (i.e., discard the wearing of a minus lens).  However you are not done at that point.

This is the reason I request that the person to teach himself how to make these measurements - if he is very serious about getting out of it.

After that, you will have some axial-myopia (which is the 20/30, and -1/2 diopter) to remove.  That will be much longer to accomplish, and it take great resolution to do it. 

But if the person has a powerful need to get to a "positive status", I am certain that most MOTIVATED people (pilots), who will keep on wearing the plus 2.5 for all near, will get there in about one year.

As always, I greatly appreciate your success, and your lecture on self-prevention.  You explained this science as an excellent engineer - and we all understand prevention in that manner.  There will those who will insist that you are not a "medical person" and do not know how to prevent entry into mild nearsightedness.  But you obviously know how to do it.

"Dr. Alex" claims...that he has "seen many hundreds of cases well into the high 5 diopter range, without any axial elongation.  Likewise, you could be at -8 diopters, and have no more than a single millimeter of axial elongation (for reference, your eyeball is about 25mm long)."

The problem is that he appears to hold contradictory positions.

First, based on the quotation above, it might be the case that he has seen thousands of cases of less than 6D that DO have axial elongation. Until we see the complete set of data, it is hard to draw reliable conclusions.

Second, elsewhere...he proposes a two-step causal process for, essentially, all myopes who wear glasses. The first stage is ciliary tension and the second stage is axial elongation. The implication is that everyone has AL if they are wearing minus glasses.

When confronted with these apparently contradictory positions, he responded:

... "It’s usually a mix of both. I am saying that you *can* show no signs of axial elongation up to 6 diopters of correction." So, here he appears to say that the two-stage, "Four Pillars" explanation does not hold universally. By using the word "usually," he seems to be saying that although there are hundreds of myopes with no AL, there are more of them with AL.

ZC,

I'm not sure there is any contradiction here.  At the end of the day, myopia is a single, unified phenomenon: a refractive defect of the eye, in which distant objects appear blurred because their images are focused in front of the retina, rather than on it.  However, this unitary phenomenon can occur for two different reasons:  (1) pseudo myopia, in which the ciliary muscle fails to relax causing the image to focus in front of the retina; or (2) axial myopia, in which the axis of the eye lengthens to such an extent that the image is focuses in front of the retina.  Either way, you've got myopia.

The two processes -- pseudo myopia and axial myopia -- are independent, but they are not mutually exclusive.  They can occur separately or together. Alex Frauenfeld, David DeAngelis and I all agree that as a biological process, myopia usually develops in two stages.  The first stage is usually pseudo myopia, typically caused by excessive near work.  I agree with Frauenfeld that pseudo myopia can be quite significant -- even as strong as -5D or -6D in his experience.  And that can occur with absolutely no axial myopia.  Hence, Dr. Alex's first statement that many myopes have no axial myopia is quite plausible, particularly if they have not entered into the vicious cycle of ever-stronger prescriptions for minus lenses.

Axial myopia is typically induced by wearing minus lenses.  While minus lenses are intended to "correct" for distance vision, they simultaneously induce hyperopic defocus during close up focusing, wherein the focal point of the images shifts behind the retina.  This induces axial elongation.   Axial elongation can also occur or be accelerated by other factors, e.g. genetics, diet, or disease processes.

It may not be common, but it is at least conceptually possible that one could have axial elongation without myopia, e.g. if the ciiliary muscles and lens are flexible enough to compensate and focus the image farther back.

The usual case of myopia, however, includes ciilary spasm. Generally, myopia comes down to reduced ability of the ciliary muscles to focus.  Axial lengthening doesn't in itself cause myopia, but it makes it much harder to focus on distant objects, particularly if the ciliary muscles are in spasm due to pseudo myopia.  So axial myopia, fueled by the use of minus lenses, merely exacerbates the problem.

Within this framework, I think that Alex Frauenfeld's statements above are consistent with one another, and also with my current understanding of the etiology of myopia.

Todd
« Last Edit: August 23, 2014, 04:38:02 PM by OtisBrown »