Astigmatism halved - spherical question

Hi everyone,
I’ve been able to half my astigmatism, it went from -1 to 0.5, which is awesome. However, my spherical is going much slower.

The strange thing is, I’m working on my spherical but its the astigmatism that’s getting better.


I’ve been four months on my revised prescription with the lowered astigmatism, but my vision still feels about the same. Should I keep going or get another eye test? Maybe the astigmatism has changed and I can’t tell?

When you look at white text on a black background at some distance, is there double vision or ghosting? Does it keep getting better? Have you checked the astigmatism fan? Do all of the lines look dark to the same extent? It helps to get a baseline and see if it is changing for the better.

Dropping that bit of astigmatism is also dropping a bit of minus correction so it makes a bit of challenge in the sphere as well. Are you reading 20/20 on the Snellen eye chart in low light conditions? And other checks of vision in the world under less than ideal conditions?


When optos add cyl to the prescription, they reduce the sph on the other parts of the glasses. (When they add -1D cyl, they reduce -0.5D from the sph. This is a standard opto recommendation to do.)
For this reason you may feel that you are stagnating with sph while cyl is improving. Just because you are reversing the standard practice.

If you want to get confirmation if it is the sph or the cyl that needs more work on with the current glasses I recommend testing vision with the below picture. I find it more helpful than the astigmatism fans.
Start from a near distance where all 4 sets of squares or circles seem to be clear. Do it with 1 eye at a time. Increase the distance and see if it is all 4 that go blurry at the same time or one of them gets blurry or greyish much sooner than the others. If the latter that confirms the cyl reduction is still in progress.

To be honest you worked on your astigmatism in the past months. This means that it cannot be guaranteed that the opto will measure it correctly either. Also there is the risk that a transient status gets measured and corrected = fixed in glasses just because your astigmatism is moving from the old value to a new value.
If you go and get it checked, take the results with healthy scepticism since optos don’t know how to allow for myopia or cyl reversal in their measurements

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