Beginner Patcher Question - Astigmatism

Hello EM! My current prescription is L -7.25 and R -5.50, -1.0 cylinder which I’ve been wearing for the last 5 months. I can AF fine but not ready for a reduction, my last reduction was a -0.25 in cylinder. Individually my R is 2X as blurry as my L so I was thinking of patching to have the R eye ‘catch up’.
I have 2 questions,

  1. Not sure which is my dominant eye couldn’t find the EM video for that but do I patch the L eye for the R eye to catch up?

  2. I’ve read in the forum that the patched eye gets more clarity post patching so does mean I patch the R eye instead?

Any guidance and experiences to help me get clear on the next step is welcomed. Thank you!

To be honest I am not sure patching is the right approach for you at this point…
Considering the way your diopter gap works out with the cylinder being heavy on the eye with less sphere I wonder have you entertained cashing in some cylinder for spherical equivalent?

I have considered swapping cylinder for spherical. But at this point reduce cylinder and add spherical OR just simply add spherical? I’ve been using this prescription for 5 months.

I expect that depends on how much blur you are dealing with, However it seems to me the trade out is the more productive more forward. Eventually you will want to remove cylinder and also eventually you will want to equalize. I expect smaller steps will make for the easiest adjustment. So in that theory you would increase by .25 sphere to the R eye and knock out .5 of the cylinder. Though I have heard of people going bigger too, in which case you delete the full 1 of cylinder by increasing the spherical .5 (It is typically a 2:1 ratio)
If you really feel the blur is that much in that eye though you could certainly add even more than the .5 spherical, trust your measurements, and make sure your diffs have the same ratios that you decide on. It still might require some trial and error before you get it just right, several people have invested in test lens kits. And still others just buy two or three options and figure out what works.
But I would still not think patching is a good fit for you at this time. Technically your R eye is already in the lead…

For me proper patching takes away too much from the overall vision.
When I feel that one of my eyes needs some extra attention I usually take an a5 size card (empty back of a post card) and hold it at my nose at an angle that the eye I want to improve (that has more blur or DV) can see what’s in front of me and has about 120 degrees vision and the other eye can see in about 60 degrees but not straight ahead. I spend about 5 minutes every now and then like this in front of the Snellen at the edge of blur clearing the text with shoulders relaxed. If I can’t clear the text I move closer and try again. After 5 minutes you can remove the card and see how much clearer the text is with both eyes…
I start from a distance where I can read each letter in my chosen Snellen line (I prefer 20/30 or 20/25 for this) with confidence but with some blur or DV and clearing the text means getting the edges of the letters sharper.
Sometimes I do it twice a day, other times I only do it every other day. I notice subtle changes day by day. So subtle that the change may only get noticed in a week’s perspective.


I have just tried this looking at the text of your post. What happens is that the very blurry image produced by the left eye is half the distance of the text higher than in the right eye which can read the text clearly. The left part of the text slopes down to the centre, as does the right bit of the text. When I use a differential lens of -3.75 for my left eye and then alternatively close my eyes, I have the same kind of dance, although not as extreme. Only recently has my visual cortex learned to bring the two images together in a readable form. This is still a strain on the visual system, so I do very little of it.

For me the text usually moves horizontally and often the paper’s colour seems a bit yellowish compared to white with binocular vision…

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