Yep, the paper is here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1979094/
I assume the idea is that the juvenile tree shrew is an animal model for human children. And yes, they were made to wear lenses.
That’s one of two papers Tippit posted as his scientific evidence to support his procedure and justify the exaggerated rhetoric of his thread title.
Abstract
Purpose.: We demonstrated that eyes of young animals of various species (chick, tree shrew, marmoset, and rhesus macaque) can shorten in the axial dimension in response to myopic defocus.
But all the animals of all species used in this trial were juvenile (as was the case with the tree shrew and human child studies). The explicitly stated mechanism is an effect on the growing eye of juveniles, that is there is a feedback mechanism in juvenile animals which adjusts the rate of axial growth to compensate for defocus and achieve emmetropy. You have presented zero published evidence that this process operates or can opeate in the fully grown adult eye.Tippit said:There are no studies that myopic defocus causes axial shortening, but the evidence is compelling, especially since it corroborates what I already know personally to be true from experience. Here is one that shows cross-species examples of this phenomenon:
https://iovs.arvojournals.org/articl...icleid=2189093
Eyes in Various Species Can Shorten to Compensate for Myopic Defocus
I have pointed out before that not all funding (not even most funding) in ophthalmology comes from frame and eyeglass lens manufacturers. Did they fund all these studies into animal models? It's not a good excuse for the complete lack of published support for your hypothesis.Now, who is going to fund studies in the species that matters? EssilorLuxxotica? Lol.
But all the animals of all species used in this trial were juvenile (as was the case with the tree shrew and human child studies). The explicitly stated mechanism is an effect on the growing eye of juveniles, that is there is a feedback mechanism in juvenile animals which adjusts the rate of axial growth to compensate for defocus and achieve emmetropy. You have presented zero published evidence that this process operates or can opeate in the fully grown adult eye.
It usually is assumed that, when eyes compensate for myopic defocus imposed by positive lenses, their rate of ocular elongation is reduced, so the eye either elongates at a slower rate than normal or, at the most, stops its growth. Even though it seems more natural that an eye in a growing animal should elongate rather than actually shorten (reduced length from the front of the cornea to the back of the sclera), there seems no obvious reason why an eye experiencing myopic defocus cannot axially shorten or shrink through a mechanism, such as extracellular matrix remodeling of the sclera, thereby further facilitating compensation. Given that tissues are remodeled continuously under homeostatic control, we ask why should axial shortening or shrinkage be more implausible than elongation or enlargement.
Our data provided evidence that avian and mammalian eyes can shorten axially to compensate for myopic defocus. That eye shortening was found in a variety of species, regardless of the structural differences in the sclera and eye sizes, suggests that the same mechanism modulating eye growth is conserved evolutionarily.
While it is true that the evidence shows compensation of pseudomyopia in children can result in axial elongation, there isn't any published evidence that I can find that reversal of elongation has been observed in human adults. Since you haven't cited any, presumably you can't find any either.
But whether or not what you claim to have achieved is a result of the process you followed (it's impossible to say based on a sample size of one, and with you being so invested in your claims), you are making an error in concluding that there are no genetic factors in progressive myopia, nor any environmental factors other than overcorrected pseudomyopia in children and adolescents.
I have pointed out before that not all funding (not even most funding) in ophthalmology comes from frame and eyeglass lens manufacturers. Did they fund all these studies into animal models? It's not a good excuse for the complete lack of published support for your hypothesis.
There is plenty of published support for my hypothesis,
In summary, we have presented an analysis of data from various established animal models of refractive error development showing the capacity of eyes in young, rapidly growing animals to shorten axially to facilitate compensation for myopic defocus. It would be interesting to determine if this phenomenon also exists in children or adolescents, since older adult human eyes have been shown to shorten axially, possibly in response to the increased refractive power of the cornea and the lens. 34 These results suggest the possibility that combining distance correction with some myopic defocus in the correct amount and duration might cause the developing human eye to shorten axially or shrink. If this were the case, then strategies for preventing or reducing the axial elongation of the eye that results in high myopia in human, and the associated ocular pathologies, might be treated feasibly.
Because the mechanism being studied is variations in the growth of juvenile eyes as a consequence of imposed defocus.This is a reasonable point, and I don't know why they only studied juveniles.
It is clear the paper is about axial shortening or elongation in the growing eye of the juvenile. This is not carte blanche to conclude that the authors are endorsing the concept of lengthening or shortening in the adult eye.But here is an excerpt from the paper:
It usually is assumed that, when eyes compensate for myopic defocus imposed by positive lenses, their rate of ocular elongation is reduced, so the eye either elongates at a slower rate than normal or, at the most, stops its growth. Even though it seems more natural that an eye in a growing animal should elongate rather than actually shorten (reduced length from the front of the cornea to the back of the sclera), there seems no obvious reason why an eye experiencing myopic defocus cannot axially shorten or shrink through a mechanism, such as extracellular matrix remodeling of the sclera, thereby further facilitating compensation. Given that tissues are remodeled continuously under homeostatic control, we ask why should axial shortening or shrinkage be more implausible than elongation or enlargement.
All of which is reasonable as a hypothetical means for a hypothetical process, but is not evidence that that process can or does actually take place.Clearly there are plenty of examples in human adult biology of tissue remodeling under homeostatic control. Chronic low blood pH results in the cannibalization and reforming of bone tissue for extracting calcium. Cellular autophagy reforms and removes diseased tissues throughout the body on a regular basis. Skin callouses are formed and removed as the result of environmental wear and tear, all outside of the post-natal growth phase in humans.
I couldn't find references to studies where hyperopic defocus causes a permanent axial elongation in adults. Could you you refer me to one. It is well documented that both axial elongation and shortening occurs as a result of transient defocus, but the effect is itself transient.And perhaps the most important and relevant evidence of all? Hyperopic defocus results in axial elongation in adults of any age.
Ah - we've got there at last. This is the point I was making which you repeatedly tried to sweep under the carpet. There is no published science which confirms that the process you claim can or does occur in human adults.So while there is no peer reviewed science that directly addresses the hypothesis of axial shortening by way of myopic defocus in human adults,
And note my highlight - this is about the growth of juvenile eyes not about long-term axial changes in adults.Reading further into the paper.
Note the bolding, conserved evolutionary.
Our data provided evidence that avian and mammalian eyes can shorten axially to compensate for myopic defocus. That eye shortening was found in a variety of species, regardless of the structural differences in the sclera and eye sizes, suggests that the same mechanism modulating eye growth is conserved evolutionarily
You have not begun to show that that is the only or even the primary cause of progressive myopia.Progressive myopia is caused by wearing eyeglasses.
There is, as I have been saying for some time, no published study which confirms your hypothesis. Since your hypothesis is about axial shortening in adults then their omission is material.There is plenty of published support for my hypothesis, you are just interested in dismissing it because of the specific omission of adults from the axial shortening studies
I will agree that your hypothesis is not an unreasonable one. But the fact remains that there is no published study to show that it is a correct hypothesis, as you have at last admitted in this post, and the circumstantial evidence, such as it is, is inadequate to justify your strong conclusion and the breathless rhetoric in the title of the thread. Could it be that no paper reporting long term axial shortening in adults has been published, because such changes do not occur?which, in context, is nonsensical and unreasonable given the circumstantial and other evidence. I don't know the reasons for the lack of studies, but I understand how selection bias plays a massive role in the (de)selection of studies to be funded and peer-reviewed.
Fine - it sets out a hypothesis that something along the lines of your process might work. As I said, your hypothesis is not unreasonable. But nor has it been demonstrated to be correct. Reference 34, by the way, is to a study where defocus caused transient axial shortening.Also from the above paper:In summary, we have presented an analysis of data from various established animal models of refractive error development showing the capacity of eyes in young, rapidly growing animals to shorten axially to facilitate compensation for myopic defocus. It would be interesting to determine if this phenomenon also exists in children or adolescents, since older adult human eyes have been shown to shorten axially, possibly in response to the increased refractive power of the cornea and the lens. 34 These results suggest the possibility that combining distance correction with some myopic defocus in the correct amount and duration might cause the developing human eye to shorten axially or shrink. If this were the case, then strategies for preventing or reducing the axial elongation of the eye that results in high myopia in human, and the associated ocular pathologies, might be treated feasibly.
Fine - it sets out a hypothesis that something along the lines of your process might work. As I said, your hypothesis is not unreasonable. But nor has it been demonstrated to be correct. Reference 34, by the way, is to a study where defocus caused transient axial shortening.
I doubt that you would have got the same negative response to an OP entitled something like "My experience suggests a neglected area of research" or "A plausible hypothesis for correcting progressive myopia n adults" or some such. What people are reacting to is your claim that your personal anecdote proves the hypothesis and that you are justified in abusing the industry (and abusing those in this thread advocating proper trials to validate claims in healthcare) on those tenuous grounds. Your experience cannot validate the hypothesis. No-one's personal anecdote can.
I assume that since I am the antagonist here making what is, admittedly an extraordinary claim, that you’re accusing me of not understanding the scientific method.Second, it brings into sharp focus something I've myself encountered more than once IRL, how well educated, otherwise intelligent people are somehow unable to quite grok the whole scientific method thing. That's interesting, because it isn't such a difficult thing to understand, and a child of ten could, if properly explained, understand this: but yet, somehow this is something that many adults, educated intelligent adults, often have a hard time understanding. That's ...curious.
I assume that since I am the antagonist here making what is, admittedly an extraordinary claim, that you’re accusing me of not understanding the scientific method.
The scientific method is about observation, hypothetical induction, experimentation, and deduction that may result in falsification of the hypothesis, or refinement of the hypothesis. Confusion arises from the fact that lots of bad science is done by bad scientists who arrive at bad deductions, sometimes with monumentally bad results (for instance, billions of people wearing lenses in front of their eyes to treat what begins as a muscle spasm). Is this a failure of science? The scientific method? No, it’s a failure of people. This is the limitation of the scientific method. People.
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Abstract
Previous theories of myopia development involved subtle and complex processes such as the sensing and analyzing of chromatic aberration, spherical aberration, spatial gradient of blur, or spatial frequency content of the retinal image, but they have not been able to explain satisfactorily the diverse experimental results reported in the literature. On the other hand, our newly proposed incremental retinal-defocus theory (IRDT) has been able to explain all of these results. This theory is based on a relatively simple and direct mechanism for the regulation of ocular growth. It states that a time-averaged decrease in retinal-image defocus area decreases the rate of release of retinal neuromodulators, which decreases the rate of retinal proteoglycan synthesis with an associated decrease in scleral structural integrity. This increases the rate of scleral growth, and in turn the eye's axial length, which leads to myopia. Our schematic analysis has provided a clear explanation for the eye's ability to grow in the appropriate direction under a wide range of experimental conditions. In addition, the theory has been able to explain how repeated cycles of nearwork-induced transient myopia leads to repeated periods of decreased retinal-image defocus, whose cumulative effect over an extended period of time results in an increase in axial growth that leads to permanent myopia. Thus, this unifying theory forms the basis for understanding the underlying retinal and scleral mechanisms of myopia development.
A role for hyperopic defocus is strongly supported by the finding that the eyes of young animals respond to minus lens wear with faster axial elongation.15–19 On the other hand, brief periods of clear vision completely negate the “grow” signal produced by otherwise constant hyperopic retinal blur across animal models.20–22 Because children would have to do constant near work to prevent exposure to the potent “stop” signal provided by brief periods of clear vision when viewing an object at distance, these results in animals question the importance of transient hyperopic retinal defocus due to accommodative lag during near work. There are also controversies over whether accommodative lag in children is elevated prior to the onset of myopia23, 24 and whether accommodative lag is associated with myopic progression.25–27
Abstract
Purpose.: To determine whether high light levels, which have a protective effect against form-deprivation myopia, also retard the development of lens-induced myopia in primates.
Methods.: Hyperopic defocus was imposed on 27 monkeys by securing −3 diopter (D) lenses in front of one eye. The lens-rearing procedures were initiated at 24 days of age and continued for periods ranging from 50 to 123 days. Fifteen of the treated monkeys were exposed to normal laboratory light levels (∼350 lux). For the other 12 lens-reared monkeys, auxiliary lighting increased the illuminance to 25,000 lux for 6 hours during the middle of the daily 12 hour light cycle. Refractive development, corneal power, and axial dimensions were assessed by retinoscopy, keratometry, and ultrasonography, respectively. Data were also obtained from 37 control monkeys, four of which were exposed to high ambient lighting.
Results.: In normal- and high-light-reared monkeys, hyperopic defocus accelerated vitreous chamber elongation and produced myopic shifts in refractive error. The high light regimen did not alter the degree of myopia (high light: −1.69 ± 0.84 D versus normal light: −2.08 ± 1.12 D; P = 0.40) or the rate at which the treated eyes compensated for the imposed defocus. Following lens removal, the high light monkeys recovered from the induced myopia. The recovery process was not affected by the high lighting regimen.
Conclusions.: In contrast to the protective effects that high ambient lighting has against form-deprivation myopia, high artificial lighting did not alter the course of compensation to imposed defocus. These results indicate that the mechanisms responsible for form-deprivation myopia and lens-induced myopia are not identical.