Myopia: its historical contexts

Hypotheses about aetiology of myopia

https://bjo.bmj.com/content/bjophthalmol/early/2018/02/03/bjophthalmol-2017-311625.full.pdf

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Nice read - as I said elsewhere, the science of today is the nonsense of the future.

Moreover, they’re focused on things they need, and not things we need (surgeons and scoliosis).
But the role of many scientists if they can’t hide the truth as it would be too obvious, is to word things the way most suitable for them (scoliosis - omit the role of muscles, omit Wolff’s law, pretty useless Risser stage - well, only Risser 0-1 describes something).
The other work is to intentionally stress on some facts while almost hiding or just not taking into account the other, less valuable or beneficial for them (the negatives of LGBT/sex research, COVID vaccine research and possibly growth research).
As well, some “leading” people of science and knowledge based on it (no one person will ever come to a fully integral vision of things) want to show their all-knowledge, but are immediately hit by a different perspective: the world simply does not work the way “one person knows all”. Those people are quickly get nervous when they see things won’t fit into the words they like to describe it or completely omit the view of scope they were never dealt with (surgeons and biomechanics, PTs and muscles science, eye science and muscles science, Linux software critics and Linux software users).

So yes, I don’t trust science. To say I will dig into every detail of research and check it myself. Assuming even I or they understood it correctly.

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To clarify, popular science that consists of popular psychology, medicine and so on.
Much more credit in real “exact science”: math, physics, chemistry, non-medical biology etc.

interesting. I haven’t seen high myopia as classified more negative than -8 D (I’ve seen -5 and -6 D thrown around), of course it’s nice since it puts me in the simple myopia domain, but is there any scientific basis for this cut-off point?

also it seems they consider anything above -0.5 D (positive direction) as NOT myopia i.e. -0.25 D is NOT myopia

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Even this will change, but as it is the best we have for the moment, I like to say ‘As far as we know…’. Of course, most of what I investigate in the fields of science is far above my pay grade. I can only tackle it with the cognitive ability and background knowledge of a reasonably intelligent, reasonably well-educated, and more than reasonably well-read (in the general sense) adult. Tough luck if the price I have paid for this is myopia.

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From the paper:

−8.00 is an arbitrary and often used cut-off point.

So: there isn’t.

then again, most thresholds and cut-off points are arbitrary in science, unless they are tied to some natural phenomena, like the freezing point of water = 0 degrees C

I guess it’d be hard to find a non-arbitrary cut-off point in myopia

one might be between low-myopia caused only by ciliary spasm and “real” axial elongation caused myopia - as they suggest in the paper, but we’d have to quantify the maximum possible ciliary-spasm-induced myopia, if possible

what would be a non-arbitrary cut-off point between moderate and high myopia? any ideas?

Great fun for those of us with one eye in each camp. :face_with_monocle:

But as my left eye (according to my own, admittedly subjective measurements) has just squeezed under the -5 (SE) line, I can now confidently say that I am not a high myope. In most studies on high myopia - often resulting from early onset myopia - I have seen -6 used as a cutoff point - just as arbitrary, I suspect.

Edit: there is some method in their madness. From a WHO document:

5. Terminology and classification
5.1 Myopia, high myopia and pathologic myopia
There is currently no internationally agreed threshold for myopia or for high myopia. An operational
definition for high myopia is necessary so that the results of population-based studies can be
conducted with the same criteria in different countries, to determine the prevalence of high
myopia, the prevalence of vision impairment and/or blindness attributable to high myopia and
to determine whether high myopia progresses to pathological myopia in a similar way and in
the same proportion in different countries, ethnic groups and socioeconomic environments.
Longitudinal studies of high myopia and pathologic myopia should be conducted to quantify
the risk for sight-threatening conditions due to high myopia.
Currently, the definition of high myopia varies by study; it has been defined as: < –5.00 D
myopia, ≤ –5.00 D myopia, < –6.00 D myopia, ≤ –6.00 D myopia and ≤ –8.00 D myopia. High
myopia has also been defined on the basis of an axial length > 26 mm. Axial length, however,
can be an inaccurate criterion because it can vary even in normal eyes. Overall eye power is
derived from a combination of the lens, cornea and axial length, and some eyes with longer
or shorter axial length have no refractive error. Furthermore, measurements using different
instruments may vary.
The participants agreed that a classification of high myopia as ≤ –5.00 D is the best definition,
as a person who has –5.00 D uncorrected myopia has a visual acuity of 6/172 (10), which is
much worse than the threshold for blindness (< 3/60 in the better eye) (35).

From https://www.who.int/blindness/causes/MyopiaReportforWeb.pdf

oh damn -5 :frowning: then again, it’s arbitrary I guess

a real milestone for me would be around -2 where you can use the computer without glasses

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I have been rabbit-holing around the association between astigmatism and myopia. I find it interesting that my eye with double the myopia of the other also had double the astigmatism. Chicken or egg?

I raise this point here, as highish myopia with high astigmatism may be a different kettle of fish altogether as far as risk for serious sight problems is concerned (hopefully less of a risk). I also remember that you started out with high astigmatism at an early age. I do not remember any of those on the forum with really high myopia also having high astigmatism (perhaps Markyan?). A mole hole rather than a rabbit hole - groping around rather blindly. :crazy_face:

My hypothesis for astigmatism is that it’s simply an error in the elongation process and/or manufacturing error in the lenses (just like the error margin for sph is 0.125 diopter for the average lenses).

There speaks a man with no astigmatism. :grin:

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