The myopia report of my son - could someone explain it to me?

This is what I could find for SEQ:

Definition of a prescription in different
Our calculation scheme makes use of
the principle of astigmatic decomposition, which is commonly used in
optical aberration theory. A prescription
in the spherocylindrical form S þ C
(S¼ sphere, C ¼ plus or minus cylinder)
and Y ¼ axis is converted into a component notation (Bennett 1986a, 1986b;
Dunne et al. 1994, 1997):
spherical equivalent (SEQ), the
mean refractive power S þ C/2 which
is constant for any given prescription;
C0 ¼ C Cos(2Y), the projection of
the cylinder to the 0 /180 meridian and,
C45 ¼ C sin(2Y), the projection of
the cylinder to the 45 /135 meridian.


A quick glance makes me think they might use that number for toric contact lenses…
This makes me think they are using + measurements for the cylinder correction - so negative sphere and positive cylinder.

Usually cylinder is measured as a negative value these days. So you may have to convert to cylinder to its negative equivalent before purchasing glasses, depending on where you buy them from…

This website lets you convert cyl from positive to negative: Transpose Rx - VirtualLens 3D
Just looking at it myself, that is pretty high astigmatism for reasonably low myopia…
Astigmatism is a bit different from myopia - it is to do ith the shape of the eye, but not to do with axial elongation in the way that myopia is. A great guide put together from our recently departed Ursa/Hannie is here, and will help you understand the difference:
Working Group on Astigmatism Guide

But do verify what I am saying - I am not an optician and I do not speak german either. I could be way off base. But this is my best effort at interpreting.

thank you so much for your reply! I do admit that it makes even less sense to me now :-D. But yes, the optometrist wanted to introduce the atropin eye drops and later the contact lenses which are being worn through the night only and they push the eye back somehow - Jake wrote an article about it that these contact lenses do cause permanent scarring.

But as the optometrist thought that I might be interested in these drops/lenses, she performed this full on examination and you are right that the numbers stated there might be used of an optician to create contact lenses for my son.

I also thought that cylinder is measured with minus and not with plus.

I do believe the optometrist told me that the cylinder of my son is -1 and his myopia is -2.

I will read trough the article posted by our late member thoroughly to see if I could help my son with his astigmatism also.

Maybe some other member does have high astigmatism too and perhaps might throw in some more thoughts??? And also ease my mind, as Im starting to panic because of my son´s high astigmatism… :unamused:

is astigmatism something which could be reversed (just like myopia) or at least improved?

Is there something as “normalised cylinder prescription” in the same way we have normalised prescription for your myopia???

The difference between positive and negative cylinder is explained here:

(make sure to read the comments too - some of the comments are better than the actual post XD )

thank you gemilygez. I think I will have to read it tomorrow. I need to calm down first. Im totally stressed and Im panicking because of this astigmatism of my son.

I dont know if all these measures like having a “normalised”, reduced prescription for the distance and having even more reduced prescription for the close-up work will work for him because of his astigmatism…

Im really panicking I will not be able to help him. I will need to read through all the links you sent me as now I just feel that his astigmatism will not improve and I will not be able to help him :-/

Astigmatism is not as complex as optos present it.
An opto can give you different diopters for the left eye and the right eye. However there are situation, when there is a difference within the eye, too, and that is called astigmatism. So the opto gives you different diopters within one eye’s prescription. E.g. your son’s right eye generally receives -2.00D SPH correction but at a certain angle (at the axis of 80) an additional correction is added, e.g. -1.00CYL which equals -0.50D SPH. (This is the formula called spherical equivalent: reduce cyl by taking half of the cyl diopter and adding it to the sph instead)
So the lense is manufactured that most of the area is -2.00D SPH but is -2.50D SPH at 80 only.


Despite of the opto hocus pocus it simply means that some part of the image in front of him gets blurry sooner than the rest. Look at the left and right side image in this post.

I’d assume that -1.00D CYL can be dropped completely if your son has never had cyl correction before.
If he had it and got used to it in the glasses, you may want to do it in 2 steps of -0.50 CYL reductions.
But the fact that he can go without glasses close up suggests to me that most probably he will by OK without cyl?

Two things to keep in mind:

  1. It’s not recommended to drop from SPH and CYL at the same time. Using the example above it would mean that the vision at 80 would get too much blur challenge which is usually manifested with double vision
  2. When correcting uneven diopters within the same eye, i.e. when dropping extra correction from the lense, the brain will have to work a lot harder on the image processing part. It’s a less linear, less predictable process.

But as 1 CYL is the same as 0.5 SPH it can be reversed the same way in most cases.


thank you Bianca. It looks like the whole myopia thing is way more complicated than I thought.

When I started improving my eyes, I did not worry about cylinder (although I had some).

Now looking at my son´s prescription, the spheric value on his left eyes is even as high as -3.25. So that looks to me like his myopia is way higher than I thought!!!

But the doctor told me that his myopia is -2 dioptres. And also when I tried to do his cm measurement, he measured on average 57 cm (in quite a low light), which is 100/57=1.75 diopter.

I was almost ready to order -1.5 diopter myopia glasses for him as normalised prescription but maybe I will better wait. As if I was to buy him glasses from Amazon, there is usually no cylinder included.

Now I dont know, if I should include his cylinder (and if so, then what height???) when buying him his first normalised glasses?

I dont want to do anything to cause him any discomfort. I just want to improve his myopia but although he has less dioptres than me, his case might not be as straightforward as mine due to this bloody cylinder!!??

Missed a part that the prescription has positive cyl.
However this will not change the maths.

Using right eye’s example:
The measure -2.50D SPH on most part of the eye and at 89 they recommend using +1.75D CYL.
+1.75D CYL / 2 = +0.875D SPH
So -2.50D SPH and 0.875D SPH (from the cyl conversion) = -1.75D SPH (with a bit of rounding)

Questions is: Did your son receive a simple correction of -1.75D SPH or were the glasses carved with CYL (-2.50D SPH and +1.75DCYL)


actually I think his glasses (which he wears at the moment and has been having for the last 1.5 years) are carved with cylinder already. But Im not 100% sure. I will go to the optician where we bought it and ask there.

If his current glasses are carved with a cylinder, should I buy him his normalised glasses with cylinder also? And if you, should the cylinder also have some reduced dioptres in the same way how we do it when we get our normalised myopia prescription?

Is it better to have glasses with cylinder or without?

And if there has been a cylinder carved already, should the new, normalised glasses be also with cylinder or am I allowed to get him glasses without cylinder?

Your thoughts are racing!!

I’d suggest you find out what he is wearing now from the opto. That is key.
Just a note: I would not buy normalised glasses from Amazon as the quality of what you’ll get is a bit of a gamble but would prefer Zenni or others.

I think the most important is to reduce the tablet time as much as possible. Second is to keep good distance from the screen. Movies on tablet are less harmful as you could place the tablet further away but would be even better to move it to a TV a few meters away from your son. Playing on tablet is an eye killer especially as these arms are short. But try to keep the most distance if unavoidable. And don’t use glasses for close up and I would say if he feels OK with it, don’t use glasses when at home either. Don’t make him struggle with blur, but if he is OK and comfortable without glasses in his room, in the kitchen, just don’t use it. Kids eyes can change much faster at the younger age. So keep the glasses for actual distance vision as long as he is OK in the other situations.

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Thank you so much Bianca and thank you for calming me down a bit with your advice. I have not been doing well as of lately, I keep worrying about my parents, they live in the Czech republic and the Corona has gotten there out of control. So I worry about them and have not seen them for almost a year now. I live in Austria - Vienna and although that is only 3 hours away, it would be very difficult to see each other at the moment :-/.

I do allow him tablet for 30 minutes a day, maximum. Not more than that. And he does not use it every day, either. I made the point that if he wants to watch his cartoons, he has to use TV instead. He looks at TV (which to me is not a close up), but as for the close up, he uses tablet once a day for 30 minutes like I said and he also sometimes does his preschool exercises and puzzles from a book. I use a good light for that and usually he does not do the puzzles for longer than 30 minutes and also not every day.

Thank you very much for advising me on taking his glasses away when at home. He sometimes does it anyways as for example he does not use glasses when playing football.

The only problem might be that when he watches TV, I would prefer to give him glasses as he tends to go close to the TV if he does not wear glasses.

Wow! Ok, backing Bianca you have to be calm to be rational here. Take a beat and figure things out before changing his correction at all. I am a mother too and I started this whole journey because I was freaking out about my daughter’s vision, so I have been in a similar place. I have since learned this is not an emergency, while it is unsettling, you already know first hand that it is not a lost cause, not need to rush and be frantic

First: Track down the details of what he is wearing currently, this is an important data point to have.

Second: talk to him, if he can see he can tell you, and if he can’t he can tell you. Let him use his correction when he feels he needs it (as long as it isn’t in close up), and he can tell you if he can see well. Anytime you can move his focus to a further distance, do it, if that means using his correction that is fine, more distance is best.

Third: Keep in mind that this astigmatism that you are worried about is likely an over corrected cylinder amount anyways. And from my interpretation on the numbers don’t qualify as high astigmatism…

Your task now is to determine how much of the cylinder he really does need, obviously you want to be certain to never give more of any kind of correction than needed, and eventually the goal is always to simplify the complexity in the correction (gradually of course). And based on his ability to use the tablet and play football without the correction I am inclined to think he doesn’t have as much of an issue with cylinder as you are concerned about. A test lens kit would be useful but if not you could order more than one correction based on his current correction and the data you collect in the next few weeks (Snellen readings over time in his correct correction will be very useful). Always measure measure measure before making any changes to correction.

If you are still a Back to 20/20 member you might revisit the child myopia add-on.


@Reannon is totally right in all points
And I suspect the glasses may be fully converted to SPH only by the opto. If not then surely overprescribed on the cylinder.

It’s important to see the faces and the micro expressions. These are the most difficult things to clear the blur on. Let him wear the glasses if that keeps him further away from the screen. Over time - I mean midterm - as his eyes improve you can ask him to try watching without glasses or ask him what the difference is between with and without glasses. But if he’s generally doing OK without glasses that is definitely good, especially if that is the case with playing football, too.
Books with good lights should not be a problem.
Take it as gradual habit changes as the habits will have to stick for his later school life, too. One step at a time.


The numbers all look bigger because they’re written in positive CYL, here is the minus CYL equivalent (which is how they would actually make the glasses).
SPH -0.75 CYL -1.75 @ 179
SPH -1 CYL -2.25 @ 170

Positive CYL correction is mathematically equivalent to a SPH correction with minus CYL correction on an orthogonal axis. Just search online for “positive CYL converter”.
So the current situation is much less dire than you are imagining.

We’re not supposed to give diopter-specific advice, but the general approach for differentials would be to see if you could take out a lot of that astigmatism correction for close up. If I were doing it I’d make the correction amount in both eyes about the same since the eyes aren’t wildly different.


Thank u guys! I must say that im much more calm after all what u wrote me! I still need to read the cylinder thingy thoroughly over the weekend to understand it properly.

I was also excited when Lloydmom mentioned the testing kit! I have looked into it and will definitely get one!

The only thing that im unsure of is to how to measure him regarding the cylinder.

As his prescription from the optometrist is -2 dioptres with sort of -1 diopter (i would guess?) Cylinder, how would i use the testing kit? Just simply putting -2 dioptre (or better slightly lower one as i think -2 diopter is with a small overcorrection) and then not using any cylinder lenses from the testing kit at all? Or just starting with the lowest cylinder possible?

I guess i have to first ascertain if his current glasses are with or without cylinder.

I must admit the whole cylinder thingy makes it a bit more complicated. I just simply wanted to measure him by using just traditional myopia lenses from the kit but not adding any cylinder lenses.

I guess i will read thru the astigmatism first to be able to understand more.

I also wanna thank Bianca, gemilymez, lloydmom and nycmao (i hope i havent forgotten anyone) for your help!

So step nr.1 for me is to find out the EXACT prescription of my son Tim and also read and understand (or at least trying as much as possible to understand) the cylinder.

Step nr.2 - ordering the test lens kit!


Once you get a test lens kit, this video is pretty good at explaining how to set up the lenses, inc. cyl.

I would imagine that once you put in the test lens frames the correction your son wears, you can proceed with the “better or worse” routine, and correct him just to the level of acuity you would want him corrected to on the snellen.

(This was good too for understanding the different lenses in a test lens kit:
The Trial Case or trial box | Optometry Instruments | Sina Motallebi - YouTube )


Dear members,

I have completed the 1st step in my project “Correting my son´s myopia”.

I went to the optician to ascertain what power of myopia and cylinder my son has in his glasses.

This was her answer:

R myopia = -2 diopters, cylinder = +1 diopter, axis = 100 grades
L myopia = -2 dioptres, cylinder = +1 diopter, axis = 90 grades

she explained there can be another way of writing my son´s glasses´ properties (she did not use any tool to calculate it, just off the top of her head):

R myopia = -1, cylinder = -1, axis = 10 grades
L myopia = -1, cylinder = -1, axis = 180 grades

She compared it to the data from our optometrist´s appointment:
R myopia = -2.5 diopters, cylinder = +1.75, axis = 89 grades
L myopia = -3.25 diopters, cylinder = +2.25, axis = 80 grades

another way of writing the medical report from the optometrist:
R myopia = SEQ -1.75 diopters, sphere = -2.5 diopters, cylinder = 1.75, axis = 89 grades

L myopia = SEQ -2 diopters, sphere: -3.25 diopters, cylinder = 2.25, axis = 80 grades

The optician said that his astigmatism got a bit worse but it is still not that bad. The good thing is that his current glasses still have the “old” cylinder carved in them.

Looking at this, the doctors are crazy. His latest prescription shows myopia on his right eye being -1.75 and he wears his glasses with -2 dioptres on both eyes. That is, if I understand it correctly.

So now I know the exact prescripton.

The 2nd step is to get the testing kit. Gemilygez, thank you very much for the video link! I will need help with getting the test lens kit, but will create a brand new thread, so that it is not confusing.

Step nr 3 - I will get ascertain his “normalised” and “differentials” and get it from that Zenni Optics.

Also another thing - I will want to test my son´s eyes in our storage room - that will be a perfect place for it but this room is only 2.5 metres long. So Im not able to use my 3 metres Snellen.

Is there any shorter Snellen than 3 metres, which I could use?

If not, I would have to bring my son to a cellar in our building. That might be funny if someone comes in whilst Im testing him there. The neighbours might then think that I have completely lost the plot :-D.

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the 3 meter chart is already not as accurate as ideal. You can test him anywhere you have enough space, just make note of the lighting conditions and as much as possible recreate them in future tests. Especially since you should be keeping him in better lighting on a full time basis it is a good idea to consider his vision in his typical light setting when deciding his future correction. Though the spot check in the basement pre-reduction is something I do. All my measuring tactics outlined in this one: Measuring your eyesight - YouTube

honestly run a quick search, ebay amazon whatever your region has along those lines.

This happens all the time. Optos either account for ocular dominance by giving the non dominant eye more correction or by dialing up the dominant eye to keep them even (they did the second one to me).

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Hi Reannon,

thank you for your link. There were 2 things I learned from your video. The first one that measuring in the cellar is really not such a bad idea and the second one - I should probably wait until being 20/25 to drop. I always dropped when I was 20/30 and I seemed struggling with my new normalised.

But the main problem was, that my cm and Snellen measurement was not consistent. I was either measuring on the balcony - the light was always slightly different there, or in my son´s room. The light and the amount of clouds etc was also always a bit different, so I could not get the right measurement. The problem also was that I looked at my cm measurement which was measured on the sunny day and then I dropped my prescription according to that.

When I had my normalised indoors (like in my office for example), where it was naturally darker, I did struggle with my vision. For instance I could not wear reduced prescription for my computer (which is 50-60 cm away from me). My normalised has not been correct for quite some time. I kept struggling with my vision but thought I was doing myself a favour.

Therefore I started doing cm measurement in my storage room and I always came up with 8-10 cm less than when I measured on the balcony or in my son´s room.

I also increased my normalised by 0.5 diopter and now I feel much happier.

I want to avoid this previous mistake when helping my son. I want to reduce his prescription in a very gentle way so that it is not a shock for him and so that he feels comfortable with his normalised. Therefore I want to go for the measurement either in our storage room or our cellar (both of them having artificial light, therefore less light than a natural light outdoors) and will probably reduce in such a way when he has 20/25 because even 20/30 might be a bit challenging. This way I will create a prescription that is “almost perfect” with a tiny bit of challenge.

You see, the thing is that I dont want him to lose his motivation. Once I change his glasses, I dont want that to be such a big change. And each drop afterwards should never be a big change, either.

I found 2 lens kits, which confused me a little. Here is a link to the first one:

104 pieces for 144 eur. The same company has another kit:

266 pieces for 138 eur.

Why is that? Why do I pay slightly bigger price for much lower amount of pieces? Im not sure which one is a better one. If there is a relation that the more pieces, the better…

I have just noticed that this forum has the prices stated in USD and the kit with less pieces also has lower price. But that was not what I found in Euros on Austrian google.

Don’t wish to be a party pooper, but I’m approaching it from the practical side…

Your kid is happy to be without glasses most of the time both indoors and outdoors, the only exception is the TV where it’s moving faces to follow which is the most complex task for the eyes and the brain and that gives him a reference / a reminder on what clear vision is.
But most of the time he is OK to get the same correction on both eyes - which is the zero SPH without glasses, and the same correction within each eye separately - which is the zero CYL without glasses.
As without glasses it is 0 SPH 0 CYL.

If I was the parent of this child, I wouldn’t even think about adding any cyl to his normalised glasses.
The risk is: if he wears them he may get used to them.
And I wouldn’t worry about measuring cyl for him either, so I wouldn’t buy a test kit.
I would just print that astigmatism wheel on an A4 paper and ask him to walk away from it and say if the whole wheel goes blurry and grey at the same time or if some part goes grey earlier.

Currently he has corrections around -2D. When he has developed some additional good habits, like wearing the glasses a bit less when at home, trying to AF on street signs or car number plates, etc, then I would drop 0.25D or 0.5D from both eyes to have the same SPH and no cyl for each eye.
If he cannot see clearly with the new normalised he will tell you.
He is quite young so I would just ask him every now and then if he can read this or that, and depending on the answer I would ask if he can see the thing clear(er) a step closer or a step further away.
At the end of the day it is not a 6m Snellen he has to read but the street and shop signs, bus numbers and the board in the classroom, plus the football mates to pass the ball to.

Just my personal opinion, I’m not a medical professional or an authorised person to give any advices on vision, etc, etc…