Dealing with changing axis numbers

Hi folks,

I ran into this thing and was wondering, if someone had an Idea how to proceed:

When I started my journey here, I was wearing following prescription:

Left: -0,25 sph / -3,75 cyl (57°)
Right: -0,25 sph / -3,50 cyl (128°)

I got myself a pair of differential glasses for close up, which I’ve been wearing for about 4 weeks now. It has this presiction:

Left: -0,25 sph / -3,25 cyl (57°)
Right: -0,25 sph / -3,00 cyl (128°)

Now, 4 weeks later I encountered something weird: I was looking at my snellen chart and for some reason closed my right eye. For my left eye then, text at the chart was slightly blurry. Then I tilted my head to the right and: the text cleared up! So apparenty, my axis number had changed :thinking: (in my right eye, there was no such effect).

So I was worried that my axis number was off too much now and would prevent me from further progress. I then did some measurements with my snellen chart and my test lens kit and found out:

  • My left eye can now see the 20/20 line well at -0,25 sph / -2,75 cyl (55°)!!! which I feel is a massive improvement!
  • my right eye seems not to have improved at all. It can see the 20/20 line only at around the starting presicription with -3,50

Since with my current prescription my left eye sees a bit blurry because the axis number is off, I’m a bit worried that my right eye might be overcompensating for the blur in the left eye and therefore doesn’t improve or might get worse.

Now, I want to order a new pair of glasses, so my left eye doesnt have to deal with the blur all the time. However, I want to give my right eye (which seems to be the “non-dominant-eye”) a chance to adapt to the new reduced prescrition before I reduce even further.

So I was wondering: should I just get the same prescrption and just change the axis number for the left eye (which is now around 45° according to my test lens kit)? That would mean that my left eye would now be over corrected for close up (as it can see 20/20 at -2,75) while my right eye hasn’t adapted to the change yet… :thinking:

Or should I take the chance and reduce my left eye for my differentials a bit more, since It has already improved by -1,00 cyl and is now better that the right one (which was the other way around in the first place!)? Of course, I would be making sure that the difference between the two eyes doesn’t become too big…

I would love to hear from you! :slight_smile:

This is interesting, as I’ve always heard of astigmatism glasses, but never thought someone here would be using them. Have you ever thought of converting it to SPH, because astigmatism can be tricky. From my experience, axis changes everyday based on your lifestyle.

3 things I can say to hopefully make you feel better.

-Endmyopia does not alter axis numbers in most cases. Doesn’t mean you can’t if you need to, though.

-People who wear spherical only, like me, aren’t as upset by such directional fluctuations. They happen. That’s life. Be happy your cyl appears to be reducing fairly rapidly!

-I’m a fan of the head tilt trick, too. When you put your head back again to the original normal angle, it often remains clear. I use it and I don’t even have astigmism. It seems to help combat intermittent directional blur if it gets bad enough.

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-Endmyopia does not alter axis numbers in most cases.

Thank you Jim for that detail, that’s quite an important aspect!

Today, I did some more testing and found out:
*When I tilt my head immediately after focusing on some text, the text appears sharper.
*When I spend some time focusing on the text and tilt my head then (say 30 secs after focusing), the image gets blurrier!

So apparently it takes some time for the eye to adapt to a new visual stimulus and “set the axis right”, so to speak.
With that in mind, I went back to my test lens kit and reconstructed my current differentials with it:

Left: -0,25 sph / -3,25 cyl (57°)
Right: -0,25 sph / -3,00 cyl (128°)

Then I closed my right eye and gave my left eye some time to focus on the new stimulus. When I tilted my head, the text got blurry as well! So my setup for my differentials seems to be fine :thinking:
Then I took my real differentials and did the same test: here, the text got sharper after tilting my head! :thinking:

This leads me to the conclusion that my differentials might not have the axis number I ordered! I will take them to an optometrist in town today and see if they can confirm that… I’ll keep you posted :slight_smile:

Damn, I was right :angry:

The optometrist confirmed:
The glass in the left eye was at 62° not 57°, which she emphasized is waaay off.

At least it confirmes that my axis numbers has not changed, which is great :slight_smile:

(Why my left eye can see well at -2,75 cyl I still dobious to me, but that’s not part of the discussion here ;-))

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