Difference between revisions of Frequently Asked Questions/Myopia
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==Does 20/20 | ==Does 20/20 mean perfect eyesight?== | ||
In most cases, an [[optometrist]] will prescribe glasses for 20/20 vision. Optometrists are not perfectly accurate in many aspects ({{awesome}}), and so you might actually have a small amount of [[myopia]] or [[hyperopia]] in reality. In a lot of cases, 20/20 does mean perfect eyesight. It means you can read the 20/20 line on a [[Snellen chart]] without using [[Active Focus]]. | |||
{{jake says|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: | |||
{{quote|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.}} | |||
==What is axial elongation?== | |||
{{also|Frequently Asked Questions/Myopia/Quotes#Axial elongation}} | |||
[[Axial elongation]] is the increase in length of the eyeball. It happens when you wear glasses and look at screens for extended periods of time. Specifically, it happens due to [[hyperopic defocus]] as a result of [[close work]] combined with [[glasses]] that are [[overprescribed]] for the [[focal distance]] in question. | |||
{{jake says|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.}} | |||
[https://www.sciencedirect.com/science/article/pii/S0896627304004933 Homeostasis of Eye Growth and the Question of Myopia] | |||
===How do I tell if I see blurry because of axial elongation?=== | |||
Blog post: [https://endmyopia.org/pro-topic-ciliary-spasm-blur-vs-axial-elongation-blur/ Pro Topic: Ciliary Spasm Blur Vs. Axial Elongation Blur] | |||
==How do I calculate all the diopter & optics maths?== | |||
See [[optics related math]]. | |||
==What is pseudomyopia?== | ==What is pseudomyopia?== | ||
[[Pseudomyopia]] is where the [[ciliary muscle]] locks up due to prolonged periods of [[close up]], typically spent in front of a monitor. Pseudomyopia is typically the condition people have when they first go to the optometrist to get a pair of glasses. That pair of glasses goes onto cause [[lens-induced myopia]]. | |||
[[Wikipedia:Pseudomyopia|Wikipedia article on pseudomyopia]] | |||
{{jake says|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. | |||
From Wikipedia: | |||
''“'''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.”''}} | |||
===Does computer work cause pseudomyopia?=== | |||
{{also|Frequently Asked Questions/Myopia/Quotes#Pseudomyopia}} | |||
{{jake says|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). }} | |||
==Why is my eyesight worse indoors or in low light?== | |||
[https://endmyopia.org/why-is-my-eyesight-worse-in-low-light-indoors-dusk-night-time/ See this blog post] | |||
==Causes of myopia== | |||
===Does computer work cause myopia?=== | ===Does computer work cause myopia?=== | ||
When you combine prolonged periods of computer work with a pair of [[distance vision glasses]], that correct you more than what you need to see the screen, '''yes'''. | |||
===Does neglected peripheral vision cause myopia?=== | |||
No. It's not clear how someone can 'neglect' their peripheral vision, as it's always there. | |||
{{jake says|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: https://endmyopia.org/peripheral-vision-loss/}} | |||
===Is myopia genetic/hereditary?=== | |||
{{also|Frequently Asked Questions/Myopia/Quotes#Hereditary factors of myopia}} | |||
[[File:Double_D_Facts_about_Myopia.png|350px|right]] | |||
No, in the majority of cases. The majority of myopia is [[lens-induced]] in the world. Question why [[Wikipedia:natural selection]] has failed so terribly it's resulted in eye defects in huge swathes of the population, two billion in the world. | |||
The Ministry of Healh in Singapore says: {{xt|"The prevalence of myopia in Singapore is among the highest in the world, with 65 percent of our children being myopic by Primary 6, and 83 percent of young adults being myopic."}}/ <ref>https://www.moh.gov.sg/news-highlights/details/speech-by-dr-lam-pin-min-senior-minister-of-state-for-health-at-the-opening-of-the-singapore-national-eye-centre-s-myopia-centre-16-august-2019#:~:text=2.,of%20young%20adults%20being%20myopic</ref> How did their ancestors survive to lead to the current generation if myopia is generally so disadvantageous to an organism's survival? | |||
{{clear}} | |||
{{jake says|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.}} | |||
===Is infant myopia normal?=== | |||
{{also|Frequently Asked Questions/Myopia/Quotes#Infant myopia}} | |||
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. | |||
===Do glasses make my eyes worse?=== | |||
{{also|Frequently Asked Questions/Myopia/Quotes#Glasses progressing myopia via hyperopic defocus}} | |||
'''Yes''', when the glasses are for distance and you perform excessive periods of [[close-up activity]]. | |||
===What is form deprivation myopia?=== | |||
{{also|Frequently Asked Questions/Myopia/Quotes#Form deprivation}} | |||
Search for 'form deprivation' in this study: https://www.sciencedirect.com/science/article/pii/S0896627304004933 | |||
==Potential solutions to myopia== | |||
===Does outdoor time reduce myopia?=== | |||
'''Yes''', when combined with a good pair of [[normalized]], [[Active Focus]] and your other habits are corrected. It's not that complicated, see [[Explainer:The Eyesight Improvement Equation|The Eyesight Improvement Equation]] | |||
{{jake says|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: https://endmyopia.org/is-going-outside-the-cure-for-myopia/}} | |||
===Can fasting improve my eyesight?=== | |||
{{jake says|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: https://endmyopia.org/intermittent-fasting-improve-eyesight-lazy-eye/}} | |||
==References== | |||
{{reflist}} | |||
Latest revision as of 13:14, 18 June 2020
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| Frequently Frequently Asked Questions (please read this!) |
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| About Myopia | LASIK |
Glasses & diopters |
Mindset | Troubleshooting |
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| Active Focus | Habits | Measurement | Normalized | Differentials | Astigmatism | Other |
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| Skepticism |
About EM | Paid course | Other eyesight conditions |
Ineffective Myopia Treatments |
Does 20/20 mean perfect eyesight?
In most cases, an optometrist will prescribe glasses for 20/20 vision. Optometrists are not perfectly accurate in many aspects (
), and so you might actually have a small amount of myopia or hyperopia in reality. In a lot of cases, 20/20 does mean perfect eyesight. It means you can read the 20/20 line on a Snellen chart without using Active Focus.
Page Template:Divbox/styles.css has no content.
What is axial elongation?
Axial elongation is the increase in length of the eyeball. It happens when you wear glasses and look at screens for extended periods of time. Specifically, it happens due to hyperopic defocus as a result of close work combined with glasses that are overprescribed for the focal distance in question.
Page Template:Divbox/styles.css has no content.
Homeostasis of Eye Growth and the Question of Myopia
How do I tell if I see blurry because of axial elongation?
Blog post: Pro Topic: Ciliary Spasm Blur Vs. Axial Elongation Blur
How do I calculate all the diopter & optics maths?
See optics related math.
What is pseudomyopia?
Pseudomyopia is where the ciliary muscle locks up due to prolonged periods of close up, typically spent in front of a monitor. Pseudomyopia is typically the condition people have when they first go to the optometrist to get a pair of glasses. That pair of glasses goes onto cause lens-induced myopia.
Wikipedia article on pseudomyopia
Page Template:Divbox/styles.css has no content.
Does computer work cause pseudomyopia?
Page Template:Divbox/styles.css has no content.
Why is my eyesight worse indoors or in low light?
Causes of myopia
Does computer work cause myopia?
When you combine prolonged periods of computer work with a pair of distance vision glasses, that correct you more than what you need to see the screen, yes.
Does neglected peripheral vision cause myopia?
No. It's not clear how someone can 'neglect' their peripheral vision, as it's always there.
Page Template:Divbox/styles.css has no content.
Is myopia genetic/hereditary?
No, in the majority of cases. The majority of myopia is lens-induced in the world. Question why Wikipedia:natural selection has failed so terribly it's resulted in eye defects in huge swathes of the population, two billion in the world.
The Ministry of Healh in Singapore says: "The prevalence of myopia in Singapore is among the highest in the world, with 65 percent of our children being myopic by Primary 6, and 83 percent of young adults being myopic."/ [1] How did their ancestors survive to lead to the current generation if myopia is generally so disadvantageous to an organism's survival?
Page Template:Divbox/styles.css has no content.
Is infant myopia normal?
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.
Do glasses make my eyes worse?
Yes, when the glasses are for distance and you perform excessive periods of close-up activity.
What is form deprivation myopia?
Search for 'form deprivation' in this study: https://www.sciencedirect.com/science/article/pii/S0896627304004933
Potential solutions to myopia
Does outdoor time reduce myopia?
Yes, when combined with a good pair of normalized, Active Focus and your other habits are corrected. It's not that complicated, see The Eyesight Improvement Equation
Page Template:Divbox/styles.css has no content.
Can fasting improve my eyesight?
Page Template:Divbox/styles.css has no content.