Course participant? Post in the forum!
Here you go. These aren’t made by me (so they’re better): https://www.youtube.com/results?search_query=subjective+refraction+ian+squire
Let’s find out, here.
There has been a most interesting discussion on Quora, on the subject of whether myopia can be cured.
Get the scoop and link here.
Here’s the breakdown: Free vs. Paid Vision Improvement
Here’s why (full article): Glasses are super dangerous.
The whole answer, skipping learning things the hard way, is here.
(In particular for high myopes, these considerations.)
The tradeoff with glasses over contact lenses (for close-up use) is:
1) Cost (you’re going through a lot of lenses coming down from high myopia, and some people prefer higher index which is also more expensive).
2) Field of vision and image quality. Less of an issue for close-up, but you are going to get less visual quality from a high diopter lens than a high diopter contact lens (in most cases, though you can get somewhat closer with some very high quality, high index lenses).
3) Convenience. You can easily get some replacement contact lenses, experiment with them for reduced diopters. You can easily put a plus lens over contacts for immediate close-up and not carrying two pairs of glasses.
All in all though, I often suggest going with glasses. High diopter contact lenses are thicker, less gas permeable, and tend to cause more corneal abrasion. They disrupt tear fluid. While it always depends on the individual, it’s important to be aware of and consider all of these factors.
Here’s the whole breakdown of what’s real, and what might be faked: http://endmyopia.org/fake-testimonials-also-lisa-reduced-2-diopters-from-7-25-to-5-25/
You should learn about all the measuring tools available, to fully understand your eyesight and myopia.
Then once you know how to do centimeter, and eye charts, how to leverage outdoor landmarks, the benefit of test lens kits, and tricks like plus lenses over contacts – then you’ll want to adapt these tools for your own myopia degree and needs.
If you have high myopia, you should read this full post, discussing measuring tools: http://endmyopia.org/pro-topic-centimeter-vs-snellen-measurement-for-high-myopia-cases/
Low myopia, especially the gap between -1.5 diopters and no-glasses, is a big, big topic. Here’s an excellent summary of things to try, issues to avoid, and generally leveling your expectations: http://endmyopia.org/low-myopia-plus-lenses-doubts-about-progress/
This is important, you don’t want to start monkeying around with lots of focal planes. Here, read this full article: http://endmyopia.org/qa-too-many-focal-plane-changes-whats-this-double-vision/
If you ended up on this question, you probably already noticed there’s no ‘buy’ link anywhere on the site.
You may have also noticed that I often repeat that everything you need to fix your eyes yourself, is entirely freely available in the blog (and the e-mail series). That’s no ploy. Yes, everything is all in the blog, see the how-to guides and reader stories, our Facebook group is also full of reader and student stories (well worth joining there as well, also free of course).
But anyway. You want to buy BackTo20/20?
Currently there is no guaranteed way to do so. The reason for all this hiding of BackTo20/20 from the general and casual reader public is that I’m still providing personal support, unlimited for all students there, via the support forum. Since I try to limit my daily time to around three hours for endmyopia, I only have limited time to do personal support.
And that’s why, no publicly available sales of BackTo20/20 (for now).
There are 10 invites that go out every month, to those who are most likely to benefit from the program. How do I know who should get them? That’s based on how you use this site, what you read, how closely you’re paying attention. Most likely if 1) you spent enough time researching here and 2) I have invites, you probably will get one.
I’m not very interested in heavily commercializing this resource for now. BackTo20/20 gives me a way to refine a structured approach, it’s also the basis of our current study for natural myopia control (the largest ever conducted), collecting participant data all along the way.
(The other, shorter answer is that you can subscribe to the e-mail course, do it in its entirety, you’ll get an invite at the end of it, if any are available – at that point you’ll already know if the DIY, free way is enough for you, or if you want a structured, Jake-supported approach instead)
No money? No BackTo20/20 invite? Or just general everything-for-nothing, freeloader type? It’s all good!
Lots and lots and lots of student readers improve their eyesight, 100% for free: http://endmyopia.org/improving-eyesight-for-free-just-the-blog/
Yes and .. sort of.
Read my full disclaimer and experience going from -5D to 20/20, in this post talking about ciliary muscle induced astigmatism – and my approach to trials vs. theoretical science:
No, 20/20 is definitely not equal to perfect eyesight.
The entire premise, the eye chart, the way your visual acuity is measured, is actually a very, very rough approximation of your eyesight. It’s “good enough” for the mainstream to “prescribe” you lenses, but you should be aware that it’s about as scientifically representative of your vision as a stick figure is of your real person.
Toshiki recently offered a very apt summary of eye chart testing, in the forum:
20/20 is just an 1861 approximation of the average visual acuity of a human. Today we know that for adolescents and young adults (up to say 35) it’s nothing unusual to have 20/10 and better vision. It’s just unusual for optometrists/ophthalmologists to actually find 20/10 or better, because…
…the optometrist’s setup with rather poor lighting tends to cut off anything better than 20/15,
…the small distances between symbols that you have for high acuity lines lead to an effect called crowding, which makes anything smaller than 20/15 hard to recognize even for those with 20/8 vision, and finally
…most eye charts stop at 20/13, which is probably a good thing, because otherwise a lot more young folks would be (jay-)walking on the streets staring at their smartphones 15cm in front of their eyes while wearing glasses that give them ants-from-outer-space vision.
Given these facs, I don’t see why getting better than 20/20 vision should require any lenses at all. On good days and with decent lighting, I am now at 20/16 without correction (only left eye, right is still 20/32…20/50).
Consider too that many jurisdictions require 20/40 vision for driver’s license exams to be passed without corrective lenses. And if you’re curious, print an eye chart online and compare your vision in shaded outdoor light to results you get with indoor lighting. You might notice dramatic differences!
So what’s 20/20?
20/20 is a barn door. It’ll do, as far as determining a ballpark for your eyesight, and a means to figure out how much lens correction will give you the clearest possible vision. Consider this, the tool used by optometry, and it’s vaguest accuracy, before ‘blindly’ trusting the mainstream lens sales with your eyesight.
This question, falls into a bit of a (definitely) advanced topic. Read the entire explainer here: http://endmyopia.org/pro-topic-ciliary-spasm-blur-vs-axial-elongation-blur/
Pro topic, this.
So you have more than one diopter of cylinder correction in your glasses.
You figured out that for close-up you don’t want to be wearing full minus (bravo!), and now you wonder what to do about that astigmatism. You read me state that less than 1 diopter, you can often just eliminate, for close-up glasses. But what about if you have more than 1 diopter?
Read this blog post: http://endmyopia.org/pro-topic-addressing-1-diopter-astigmatism-for-close-up/
You’ve read the over-hyped, over-quoted ‘study’. “Outdoor time delays myopia onset in children”
In fact, if you know even the basics of human eye biology and how myopia happens, you’re not falling for that clickbait nonsense, ignoring basic causality (myopia onset is delayed in children not because of the magic qualities of outside, but because … there are no screens outside – duh).
But outdoor time does hold the key to improving vision. That’s a bit of a longer topic, look at the full article here: http://endmyopia.org/must-read-going-outside-to-improve-your-eyesight/
Natural myopia control is still very much on the experimental side of things.
Nonetheless, there are lot of licensed professionals interested in more holistic ways of dealing with myopia, than endless lens prescriptions, invasive and dangerous laser surgeries, or poisonous substances (atropine, etc).
You can find a behavioural optometrist who is likely interested in alternatives to above.
There is also individuals like Despina, our own contributing licensed optometrist, who find natural myopia control to be an effective tool to protect their eyesight (of course nothing here on the site is licensed or medical advice, or officially endorsed by the mainstream).
We also get quite a few doctors and health care professionals interested in our method. Take a look here: http://endmyopia.org/the-word-is-getting-out/
Stuck on a plateau, were doing great for a while but now no longer improving your eyesight? Check out this brilliant update from Jon. Super worthwhile.
We don’t currently have a good way to save these kind of epic forum posts separately, so they end up floating down the river of stories and updates. (and that’s why I stuck it here in the FAQ, apologies to those browsing here without forum access)
If you are stuck on a plateau and aren’t improving, Jon’s post is fully of exactly the juicy bits to get you thinking, troubleshooting, find your way out of the sticky plateau.
If you look at the student progress reports on improving eyesight, you probably noticed that some improve much faster than others.
Lots of mainstream parrot “journalists” have recently quoted a Chinese study, claiming a causal relationship between outdoor time and myopia.
Unfortunately (or is that, unsurprisingly), they’re wrong. Don’t listen to people not smart enough to make the distinction between correlation and causality. Instead, read this actual explanation of what’s going on with outdoor time and myopia: http://endmyopia.org/is-going-outside-the-cure-for-myopia/
A 2007 NCBI published study shows a strong positive correlation between restricted peripheral vision, and myopia onset.
Jake though, has reservations. More on all that, here: http://endmyopia.org/peripheral-vision-loss/
A totally advanced question, for students who made it past blur, and are working on resolving double vision images (visual cortex activity, vs. in-eye activity).
The text too is here. And really any similar large font/small font combo will work (like billboards are sometimes awesome).
A quick and simple way to test your eye strain is key to keeping your eyes healthy.
While it may take a little creative doing at first, if you know the way to test eye strain, you’re already halfway to better vision health.
Here’s a great post on how to create a work setup that allows you to test for eye strain easily.
Or as you may ask, can the human eyeball grow shorter, reversing axial elongation caused myopia?
The optometrist says no. But optometry science seems to think it’s possible (and have demonstrated it in a number of species with human-like eyes):
Short answer: You have the wrong prescription!
But, you say, the optometrist says I’ll get used to it. Still, your headache isn’t imaginary, and you didn’t have it before you put on those glasses. What does that tell us? The optometrist is, simply, wrong!
I’ll show you how you can measure your own eyesight, and explain exactly what causes the headaches, in this post: http://endmyopia.org/headaches-because-of-glasses-the-fix-might-be-simple/
If you’re way, way into the process, and you encountered the formula blur > double vision > clear before, then this one is advanced research material for you:
Your prescription currently likely includes spherical, cylinder, and axis correction. These numbers aren’t probably even all the same, for both eyes. That’s prescription complexity, and it’s often not good for you, and likely not even necessary!
For the whole detailed explanation of how to reduce prescription complexity, visit this post: http://endmyopia.org/pro-topic-how-to-reduce-prescription-complexity/
Semi-pro topic, this one. A supportive optometrist is a great idea for any type of lens adventure. Be aware of local laws regarding prescription lenses. This as usual, not optometry or medical (as if!) advice.
Sometimes we get students, just starting out with BackTo20/20, already having changed their distance lenses, as well as the close-up. Not ideal! This erroneous approach tends to manifest in forum posts, trying to untangle what now doesn’t flow with the initial set of instructional sessions.
I explain the reason why I discourage changing both close-up and distance at the same time (for the first time), again in a recent forum thread:
The course deals with close-up first (since that’s the most common user scenario). We don’t want to change both primary focal planes at the same time (close-up and distance), to avoid introducing too many variables. Also, it’s likely that your vision will change notably in a matter of weeks, with active focus stimulus and less strain. So we go differential first, and then 4-6 weeks in we look at centimeter changes, see what may have to be adjusted, and then pick a new distance prescription based on it. This also preserves the diopter ratio across prescriptions (important), and reduces the time to adjust to a new distance prescription notably.
Understanding how prescription lenses work, even with the systematically tweaked simplification, takes a moment or two. You don’t want to mess with lenses, until you properly understand how they work.
Then you want to understand how diopters affect your vision. You need to actually learn what the blur horizon is, measure it, and make an assessment how that translates to the diopters you need.
We make this as simple as possible (and it’s quite elegant, dare I say). But it’s still an undertaking. And the first differential (close-up lens) is going to be a bit of a “best guess” scenario. Why?
You might opt to remove astigmatism correction for close-up. You may be looking at correcting diopter ratio between left and right eye, if your own measurements don’t reflect your current prescription numbers. And then, with all that done, and ideally correct, you’ll still realize that in a matter of weeks that close-up correction is stronger than you need.
That could be the case even if you did get it right from the start. And yet, with some active focus experience, lowered strain, and just a few weeks of time, your vision may have measurably improved. This means of course, another reduction.
Take all of the above into account. Would it be a good idea to complicate this experience, by doing all of this for a reduced distance prescription at the same time? It’d be not fun and likely stressful!
Instead of doing that, it’s ideal to keep the familiar distance correction, until at least the first successful close-up (differential) reduction. My rule is to pick your normalized (reduced distance prescription) along side of your second differential (close-up) lenses. At this point your first bit of improvement has told us what we need to know about your vision, you know how to measure, and you know that reduced distance prescription will be the correct one.
And it eliminates all the potential stress, second guessing, and you don’t expose your visual cortex to all sorts of unnecessary potential strain in the process.
You also save some money this way, you keep a familiar distance focal plane, your brain is happy, and you don’t mess with the much more critical distance prescription (critical for actually seeing clearly at a distance) until you’re ready for it.
Structure is key. You can go mess around with lenses, not with this approach, but odds are that you won’t enjoy that outcome.
All of these things, based on a decade of experimenting, trial and error, understanding vision biology and optics, conferring with friendly professionals, getting feedback from participants. I try to share as much as possible in the blog, to enable you to take care of your eyeballs, even if you can’t get a spot in BackTo20/20. If you like these guides, say thanks via e-mail, or comment on Twitter, or our friends and family YouTube channel.
I have mixed opinions about the use of plus lenses. A recent forum reply sums them up fairly well:
I’m not a huge proponent of plus in general. For kids and prevention, yes. For professionals who need insane distance vision, yes. For those who need a lot of stimulus to make progress, yes.
Generally, for the large majority of myopes, with the standard lifestyle (lots of close-up at work, not much outdoor time, a lot of playing on smartphones and TV), not so much. If you’re just looking for 20/20, not needing glasses in generally all conditions, it’s just not a necessary component in a lot of cases.
He says, adjusting his plus lenses while writing this post. ?
Plus is one of those things that’s got as many downsides as potential benefits. If you’re headed towards presbyopia, plus is risky business. You might substitute plus close-up for an extra hour of outdoor time, the latter of which would be more beneficial and give you better than equal results compared to plus use. But knowing you can just grab plus and work another hour, I’m not the biggest fan of. It’s also more lenses, which I generally like to get away from when there are natural focal plane alternatives. The whole thing of where we love to reach for some kind of tech, a product, a “solution”, I try to limit that reflex. Instead find that internal space, taking that breath, accepting a real world, appreciating it (ommm shanti, Jake). You want that good vision to go see good things.
If you like the plus, you’re getting stimulus, use it. If it’s experimenting, you like to try something new, it’s cool and curious, by all means. Use it. Above is just a bit of additional perspective.
As always, don’t go monkeying with lenses, unless you really know what you’re doing. An open minded (and actual science minded) optometrist is always a potentially handy guide in this process.
Semi-related, some thoughts on “plus lens therapy”: https://www.youtube.com/watch?v=X4k30dbjSc0
For those who get all huffy when I poke at plus lens therapy: It’s all not to say that plus lenses are bad. It’s just potentially misleading to refer to a focal plane stimulus based approach by a specific lens type. Great way to confuse people, and it’s also far too lens-centric of a thought process to make me feel comfortable. What helps your eyesight is strain reduction and positive stimulus. The kind of lens you may or may not need for this, secondary (and different for one person to the next).
This, absolutely a pro topic. If you’re a casual reader, skip this one!
As you start practicing active focus with reduced diopters, you realize that your environment doesn’t fade straight to blur, from clear vision. Instead there is an intermittent layer of double vision, almost as though your eyes are trying to hang on to the clear image, and slowly losing the battle over to blur.
We talk about the causes of this double vision experience quite a bit here in the blog, over in BackTo20/20, and in the forum. It’s a key experience, and an important part of challenging your visual cortex in your vision improvement process.
What you notice after a while is that you can actually clear written text at increasing distances, relative to your lens correction, as you get better at active focus. The range at which you experience double vision images continues to increase, and this experience becomes in part almost independent of the blur horizon. As you dig in at this stage, you might wonder just how much of this double vision is appropriate, and how to control the extent to which you experience it.
I just provided a lengthy answer to this very question over in the forum. Since it applies to everyone working on their eyesight, here it is for blog posterity:
A few pointers: A removed astigmatism correction may make the double vision images difficult to clear (for a while). Adding some part of it back in can help reduce that effect and make it easier to resolve the double vision.
If that’s not the case, then generally adding a little more correction will reduce the double vision effect. Especially once you get good with active focus, you notice that you get quite a bit of latitude in how much distance you can clear with it. To dial in how much double vision images you are comfortable with, increasing or decreasing your normalized prescription is very effective.
Another note here, sometimes the double vision aspect is a subjective matter of comfort level. If it doesn’t actually bother you, or it’s just new, or you worry about having to resolve it perfectly, it might also be something to de-emphasize a bit. For example I was always one of the slow improving cases and I needed quite a bit of stimulus to continue progressing (some need much less). So I was always using lenses with low enough relative diopter correction to give me lots of double vision challenge. Whenever I went to a less challenging correction I’d stop making progress, so I learned to make that work for me.
It’s all about fine tuning your lenses to where you’re comfortable with the challenge, and then keeping a bit of a log to make sure you get around 0.75 diopter a year of improvement at least (0.25 diopter reductions ever 3-4 months on average).
As always, the disclaimer: Don’t go monkey-ing around with lenses if you aren’t absolutely clear on how it all works. Find a friendly optometrist to help you! And of course, if you can get your hands on a BackTo20/20 invite, also a great way to go.
James asks in the forum:
I was wondering when the best time to reduce the normalized prescription is. I feel like with past reductions I may have done them earlier than necessary, resulting in less enjoyable vision and slower progress.
I think I heard from the blog or forum that when you can see 20/20 consistently for two full weeks it is a good time to reduce. Is this the case? If so, is this 20/20 in outdoor light, 1000 lux, or a more typical 200 lux scenario?
Here’s what I tell James, and a good set of guidelines for you:
What tends to work well is to reduce after you reach the same acuity as with your previous prescription. Ideally you’d wait a while before changing from there (a few weeks at least). So if you set yourself 20/20 in indoor light as your comfortable baseline, you’d change again a few weeks after you hit 20/20 with the new normalized.
The rationale here is that you have your own blur horizon distance preference. Some like 20/50 indoor, some are more comfortable with a 20/30, for example.
Initial reductions are a bit more volatile, since you initially tend to start with an overprescription, and your first normalized just brings you down to 20/20 or 20/30. Eventually, for most, an indoor 20/50 works well (since it translates to an outdoor 20/30 or better). But once you are in a groove of reductions, changing when you hit the target Snellen line works well.
Another caveat is plateaus. IF you find yourself not ready after 4 months on the same prescription, sometimes forcing the next 0.25 bump can help restart stimulus (though that one, check with me first).
Somewhat of a misguided question.
Let’s cover that though anyway, and also a possibly more helpful way to approach the topic, here: http://endmyopia.org/how-fast-can-i-improve-my-vision/
Best to browse the links, from the summary page here:
There is nothing wrong with your eyes.
Myopia is created by close-up strain first, by stimulus created by your glasses, later on. Your eyes are fundamentally completely healthy. They are simply responding to stimulus, and strain.
To fully understand myopia, you will want to spend some time exploring myopia science.
Short answer: I’m perhaps not the guide the “discount please” individual is looking for.
Long answer: For those looking for “cheap”, or are “just browsing”, “or maybe, sometime”, and definitely the “I’d surely do it if only it was x-dollars”, and “I’m poor, give me a discount” crowd .. there are lots of alternate options, ranging from entirely free to appropriately inexpensive:
- There are some worthwhile books on Amazon.com (check for the well reviewed ones).
- A local behavioral optometrist. Always worth considering.
- Sites and forums. (gettingstronger appears to have decent conversations)
I’m not specifically endorsing any of them. But there are valid ideas out there.
I’ve spent quite some time working with the “discount, please” crowd, and I’ve learned from them. It’s actually almost never about the money. It’s a mindset making excuses. There are plenty of cheap books, some of them with good reviews.
Similarly, from the Q&A: Oh, I wish I would have bought it when …..
First, remember the causes of myopia. #1 Close-up strain and #2 lens-induced myopia from increasing prescription lens use.
The only way to fix myopia, is to address the causes.
That being said, intermittent fasting can help with some aspects of myopia rehabilitation. If you are already working with reduced prescriptions, getting good breaks from close-up, and getting focal stimulus, adding small fasts might add to your experience.
For a detailed look at fasting and eyesight, take a look at this article: http://endmyopia.org/intermittent-fasting-improve-eyesight-lazy-eye/
If you want to check your prescription strength needs at home, you probably want a test lens kit. While this isn’t completely necessary for most people, you might opt to invest in a test lens kit for yourself.
There are a lot of places to buy test lens kits. They range from a few hundred dollars to thousands, depending on the quality and the sales outlet.
Here is an article on what to look out for, and suggestions on where to look for kits as cheap as USD100: http://endmyopia.org/where-to-buy-a-test-lens-kit/
No! Eye surgery to correct myopia is a truly terrible idea (in most cases).
The FDA (U.S Food & Drug Administration) reports serious side effect incidents in over 45% of post-surgery patients. These are often serious, and almost always entirely uncorrectable. Once you had laser surgery, you are stuck with the results.
What isn’t discussed much elsewhere, is the stimulus that is now created in your eye that will continue to cause the eye to elongate. This can lead to very serious risk of retinal detachment.
For more on laser surgery, visit this article.
First, you want to make a finer distinction, between the well-intentioned by nonetheless worthless content online, and genuinely willful scams.
The well-intentioned usually fall into the Bates method category. Bates was an early 20th century practitioner who found a workable solution to deal with pseudo myopia. Unfortunately most myopia today is of the lens-induced, progressive sort, so Bates practices don’t apply. Sites that promote Bates usually don’t have the training or education to fully understand the underlying biology that they are trying to repair. Because of that, while often well-intentioned, these types of approaches tend to fail for most people.
Well-intentioned sites are often not easy to assess, since they can have a loyal following and strong supporters. The best way to tell is to understand the basic premises of myopia yourself (the two stages, ciliary vs lens-induced, strain, axial elongation, etc). With that, you can look at their premise and get an idea of whether a) they know what they are talking about and b) whether their method deals with real causes in a meaningful way.
Does it sound hoakey? Are words like “eye exercises” and “palming” used? Do they advocate eye vitamins, use a bunch of pseudo science terminology?
Then it’s probably not going to do anything for you.
Scams are much easier to tell. Here is what you want to be looking for:
1) Does the site have a slick sales letter? If you are scrolling and scrolling through testimonials and promises and “but wait there is more”, and “special promo pricing”, then it’s almost certainly going to be a scam. How many legitimate services use a sales letter? None. Click out of those things.
2) E-mail collectors. If the first thing you see is a pitch to get your e-mail, it’s going to be a scam.
3) Appealing to your inner greed. If the pitch sounds like something you really wish to be true (because it sounds so quick and easy), then it’s probably a scam. “Fix your eyes in your sleep”, or “the #1 secret to better eyes”, or “fix your eyes in 30 days”, that’s always, forever going to be a scam.
4) Eye vitamins. If you see the words “eye” and “vitamins” anywhere in the same paragraph, click away. It’s a scam.
5) Mailing you products. There is zero need for a product. Usually the product is tied to some complicated return policy and refund policy. You need to return the product to get a refund, and they count on you not doing that. If there’ s a product involved, it’s probably a scam.
6) No community. If there is no way to tell on the site that the creators are active and participating in the dialog, if you can’t tell what customers are saying, if everything is shrouded in mystery and sales, you know what … it’s probably a scam.
7) The biggest scam of all – doctor promoted products. Ortho-k and the whole ilk. Yes, they work (sort of, temporarily) and yes, they are promoted by a large network of real ophthalmologists. Again though, you are being sold a product, and it doesn’t in any way address the root cause of myopia. It’s legit but it’s still a scam.
8) The payment method. This is a bit of an insider trick. Payment processors that accept shady businesses (adult entertainment, internet pharmacies, etc), are hard to get your money back from. If they payment processor isn’t clear, avoid the site. If it is, Google it. If they advertise “high risk payment processing”, run. Those outfits you’ll never get your money back from.
Instead, look for legit payment processor. As much as Paypal isn’t so amazing in many ways, it’s a good payment processor If you complain to Paypal, you get a refund. If you complain to American Express, you get a refund. If you complain to Square, you get a refund. If you complain to some shady payment processor, you’ll possibly get nothing.
Let us know when you find scams. We’ll make an effort to put together a scam-directory of sorts, at some point. Scams hurt everybody, not least of all the guys who legitimately want to help you recover your eyesight.
The #1 cause of retinal detachment is myopia. No question about it.
Too lazy to visit the link? 4 fold risk increase for mild myopia, 10x increase for high myopia. This is because increasing myopia causes axial elongation of your eyeball, which in turn stresses the attachment points of your retina inside your eye.
Preventable? Yes. Reduce your myopia.
More articles on the subject: http://endmyopia.org/?s=retinal+detachment
Glasses are bad news. Glasses facilitate the transition for pseudo myopia to the much more dangerous progressive, lens-induced, axial elongation myopia.
But you should not simply stop to wear glasses. This won’t improve your eyesight to a satisfying degree, and just cause more strain, discomfort, and possible hazards to your safety as well.
More about not wearing glasses, here.
The differential prescription is a reduced prescription specifically for close-up use.
Using a full prescription meant to correct myopia at long distances while focused up-close, will lead to more lens-induced myopia. To reduce the eye strain and focal plane change associated with full prescription wear up-close, we use a prescription specifically for close-up.
For myopes <2 diopters: No glasses should be necessary for close-up.
For myopes >2 diopters: Often a reduction of 1 to 2 diopters makes sense for close-up. To determine the exact prescription one may use a test lens kit, or a visit to a rehab sympathetic optometrist, or extrapolate the correction need by using the centimeter calculator.
Rehab specific: Reduction of prescription to introduce an ergonomically comfortable blur horizon is well advised.
How to choose a differential prescription is here.
The blur horizon is a #endmyopia Method concept. It is the space between a perfectly clear image, and the slightest degree of blur.
Finding the blur horizon allows one to measure their myopia degree, track vision improvement progress, and create positive stimulus through active focus.
More about the blur horizon is here.
Active focus is a core principle of myopia rehab according to the #endmyopia Method. It stipulates that you need stimulus to improve your eyesight.
#endmyopia is based on habit changes rather than exercise routines. To that end, active focus is introduced as a way to challenge the eye to get clear focus from a slightly blurred image. The eye is capable of resolving a small degree of blur when challenged, which provides the positive stimulus necessary for long term vision improvement.
More reading and the active focus how-to is here.
Most children are born hyperopic or myopic. Over the first few years, their eyes grow to be approximately emmetropic, with least variability at about 6 years of age.
“1. The manifest refractions of 72 children were tracked at regular intervals starting soon after birth and continuing for 9-16 y. Near-retinoscopy, a non-cycloplegic refraction technique, was used for children aged 0-3 y, and non-cycloplegic distance retinoscopy after 3 y. Almost 1400 refractions have been obtained from this group. 2. During the first 6 months the mean spherical equivalent of the group is negative by a small amount. By one year of age the children have an average of 0.5 D of hyperopia which they maintain until 8 y. After 11 y the mean spherical equivalent once again becomes negative, largely because some of the children are becoming myopic. 3. The dispersion of refractions is largest shortly after birth and smallest at 6 y, reflecting the process of emmetropization during the preschool years. 4. The spherical equivalent at 1 y is most predictive of later spherical equivalents. Correlations of spherical equivalent at 1 y with other ages range from 0.43 during the period of emmetropization to 0.76 at some later ages. 5. Children with a negative spherical equivalent in infancy in conjunction with either against-the-rule astigmatism or no astigmatism are more likely to be myopic at school age than children with infantile with-the-rule astigmatism. 6. There is an increased incidence of myopia in children with two (compared to zero or one) myopic parents.”
“Form-Deprivation Myopia. If, instead of being defocused by lenses, the images on the retina are obscured by diffusers or lid suture, eyes elongate and form-deprivation myopia results in all species studied (for example, tree shrew, Sherman et al., 1977; marmoset, Troilo and Judge, 1993; chick, Wallman et al., 1978; rhesus macaque, Wiesel and Raviola, 1977; mice, Schaeffel et al., 2004). Because no images are brought into focus by the excessive ocular elongation, it continues as long as vision is obscured, resulting in eyes whose vitreous chambers are as much as 25% longer than normal (Wallman and Adams, 1987). This dramatic response, conserved widely across taxa, implies that image quality is normally involved in restraining eye growth. When the diffusers are removed, causing the visual system to experience myopic defocus, the choroid thickens, the rate of ocular elongation slows, and the refractions return to normal.”
Axial elongation is the elongating of the eyeball. Speculation abounds as to the causes, though the most accepted is that axial elongation is just part of the whole story. Axial change, rather than axial elongation alone should be considered as a mechanism by which the eye compensates for focal plane error.
“The homeostatic control of eye growth functions to keep images sharply focused on the retina. Therefore, if the eye length increases more slowly than does the focal length, the focal plane will be behind the retina, creating hyperopic defocus on the retina. The same occurs if one puts a negative lens over the eye (Figure 2A). To regain sharp focus, the retina needs to be displaced backward to where the image is. This is done in two ways: the eye is lengthened by increasing the rate of growth or of remodeling of the sclera at the posterior pole of the eye Gentle and McBrien 1999 and Nickla et al. 1997, and the retina is pulled back within the eye by the thinning of the choroid, the vascular layer between the retina and sclera ( Figure 2B; Wallman et al. 1995 and Wildsoet and Wallman 1995); once distant images are again focused on the retina (emmetropia), both the rate of ocular elongation and the choroid thickness return to normal.
Conversely, if the eye length increases more quickly than the focal length does, the image will be formed in front of the retina, creating myopic defocus. The same occurs if one puts a positive lens over the eye (Figure 2A). The eye compensates first by expanding the choroid, which pushes the retina forward toward the image plane, and then by slowing ocular elongation, which causes the continuously increasing focal length of the eye to move the image plane back to the retina (Figure 2B; Hung et al. 2000 and Wildsoet and Wallman 1995).
The range of lens powers compensated for is greater in chicks than in monkeys, although monkeys can also compensate for stronger lenses if the lens power is stepped up gradually Irving et al. 1992 and Smith and Hung 1999. The greater range of compensation in chicks may be due to the chicks’ viewing objects at closer distances (reducing the effective power of the positive lenses), to their visual acuity being lower, and to their amplitude of choroidal compensation being greater (Flitcroft, 1999).
In addition to these changes in eye length and choroid thickness that occur over days or weeks, the eye can change the focal length of its optics in a fraction of second (ocular accommodation). These three processes all act to put the image onto the retina (Figure 3).”
Yes. Or rather, most likely.
Glasses are a simple solution to a complex problem. They change the focal plane inside your eye in a static fashion – meaning, unlike your eye which can refocus at many distances, glasses simply make a “one size fits all” adjustment to your focus.
This isn’t so much a problem if you have axial elongation based myopia. If you have pseudo myopia this treatment will likely cause progressive myopia (increasing myopia, worse vision).
The biggest problem with glasses meant for distance vision is when they are worn while focused up-close. This activity when prolonged significantly contributes to progressive myopia, and should be avoided. If you are already myopic and can’t see well enough up-close, a differential (reduced prescription) should be used for close-up work.
Glasses cause lens-induced myopia. A large body of research substantiates this fact. From the American Academy of Optometry:
Axial Myopia Induced By Hyperopic Defocus
“This study investigated whether adolescent guinea pigs can develop myopia induced by negative lenses, and whether they can recover from the induced myopia. Forty-nine pigmented guinea pigs (age of 3 weeks) were randomly assigned to 4 groups: 2-week defocus (n = 16), 4-week defocus (n = 9), 2-week control (n = 15) and 4-week control (n = 9). A −4.00 D lens was worn in the defocus groups and a plano lens worn in the control groups monocularly. Refractions in the defocused eyes developed towards myopia rapidly within 2 days of lens wear, followed by a slower development. The defocused eyes were at least 3.00 D more myopic with a greater increase in vitreous length by 0.08 mm compared to the fellow eyes at 14 days (p < 0.05). The estimated choroidal thickness of the defocused eyes decreased rapidly within 2 days of lens wear, followed by a slower decrease over the next 4 days. Relative myopia induced by 4 weeks of negative-lens treatment declined rapidly following lens removal.”
More reading here.
Also worthwhile reading, from ScienceDirect:
“Spectacle Lens Compensation. The homeostatic control of eye growth functions to keep images sharply focused on the retina. Therefore, if the eye length increases more slowly than does the focal length, the focal plane will be behind the retina, creating hyperopic defocus on the retina. The same occurs if one puts a negative lens over the eye (Figure 2A). To regain sharp focus, the retina needs to be displaced backward to where the image is. This is done in two ways: the eye is lengthened by increasing the rate of growth or of remodeling of the sclera at the posterior pole of the eye Gentle and McBrien 1999 and Nickla et al. 1997, and the retina is pulled back within the eye by the thinning of the choroid, the vascular layer between the retina and sclera ( Figure 2B; Wallman et al. 1995 and Wildsoet and Wallman 1995); once distant images are again focused on the retina (emmetropia), both the rate of ocular elongation and the choroid thickness return to normal.”
Pseudo myopia or NITM (near induced transient myopia) is a vision deficiency caused by a focusing muscle spasm – generally from excessive close-up focus.
It is referred to as “pseudo” myopia or “transient” myopia since it is just a muscle spasm. If you stop the strain activity, the muscle will eventually relax, and the myopia symptom will simply disappear.
Problems arise when this early myopia is misdiagnosed and treated with lenses.
“Pseudomyopia refers to an intermittent and temporary shift in refraction of the eye towards myopia, in which the focusing of light in front of the retina is due to a transient spasm of the ciliary muscle causing an increase in the refractive power of the eye.”
Further reading here.
Maybe. Sort of.
All myopia starts as “pseudo myopia”, also referred to as ciliary spasm myopia or NITM (near-induced transient myopia).
This isn’t real myopia, in that it would just go away if you stopped the excessive close-up focus. A whole lot of computer work, every day, never stopping that strain, does cause pseudo myopia. This can show up to be anywhere from 1 to 1.5 diopters at an optometrist exam.
Computer work alone (or reading books, or any other consistent close-up focus) doesn’t cause myopia higher than 1.5 diopters of optometrist diagnosed correction. It’s not until you begin to wear glasses, that real myopia happens (lens-induced, axial elongation myopia).
“Until the past decade or two, the conventional wisdom had been that myopia was principally genetic in origin both because of the higher incidence of myopia among the children of myopic parents and the large differences in myopia prevalence among ethnic groups (Mutti et al., 2002). This view was weakened by the discovery of homeostatic control of refractive error in animals, including primates. This gave credibility to the epidemiological evidence accumulating over decades that visual factors might contribute to myopia in humans. The evidence is of three types. First, there are epidemiological studies in many countries showing an association between the educational level attained and the prevalence of myopia (e.g., Goldschmidt 1968 and Sperduto et al. 1983), ranging from 3% for unskilled laborers to 30% for those with university educations. Second, a high proportion of young adults who do intensive professional studies (medical, law, engineering, or pilot school) become myopic over the few years of study (e.g., Kinge et al. 2000 and Zadnik and Mutti 1987). Third, cultures in which people lead outdoor lives have little myopia (Morgan and Rose, 2004), but when compulsory education and the other attributes of modern Western culture were introduced to Inuit or American Indian villages, there was a 4-fold increase in the incidence of myopia within one generation (Bear, 1991), although it is difficult to dissociate the visual changes from dietary and other changes (Cordain et al., 2002). The thrust of these findings is that education is associated with an increased prevalence of myopia. The risk factor most discussed as the intervening variable is reading, because the nearness of the page presents the eye with hyperopic defocus. Although the accommodation system reduces this hyperopic defocus, it cannot eliminate it, because accommodation is under negative feedback control, with defocus being the error signal that drives the accommodation output. Therefore, it is plausible that continuous hyperopic defocus during reading drives the emmetropization mechanism to correct this apparent refractive error by making the eye myopic.”
No. And yes.
Myopia has two primary causes (or stages). Ciliary (focusing muscle) spasm, also referred to as pseudo myopia, or near-induced transient myopia. It then becomes lens-induced myopia if you start wearing glasses.
The degree to which your myopia will increase with the second (lens-induced) stage, depends on genetics to some degree.
From the British Journal of Ophthalmology:
“In populations with little genetic heterogeneity, such as Inuit populations, studies have revealed that within a generation, the incidence of myopia has risen dramatically in line with the onset of formal education and literacy.3 4 In addition to this evidence for an environmental contribution to the aetiology of myopia, there is also abundant evidence for a genetic influence. These contrasting lines of evidence have stimulated the long running “nature versus nurture” debate, although it is now clear that myopia results from the interaction of environmental and genetic factors.5However, the observed increases in myopia over a generation indicate that the modern myopic epidemic is being fuelled by environmental changes. Furthermore, environmental influences are more easily altered than our genetic make up. Understanding how the visual environment can influence eye growth should therefore be central to any attempts to alter the natural history of myopia.”
Further reading: http://bjo.bmj.com/content/82/3/210.full