Glasses prescription question

[iwb100]

Hi All,

I was diagnosed at 20 and I'm now 35. Thankfully my corneal distortion is off centre and my vision hasn't been too bad really. In fact RGP's and kerasofts did not significantly improve my VA over glasses. So I stuck with glasses. I've found a few good opticians who prescribe well and will give me a double appointment so not a problem but recently we moved to a different part of the country and had to go to a vision express as my vision was not as sharp as I'd like.

Sumultaneously I had a scan with the specialist to ensure my vision issues weren't down to further progression which thankfully they weren't. Hopefully progression has stopped for now at least.

Anyhow, my glasses have been prescribed. My right eye basically has the same prescription as 4 years ago (unchanged in that time) apart from an increase in sphere of 0.25.

My left eye though has a sphere increase of 0.50 from 1.5 to 2.0, and a cylinder decrease (as in less correction) of 0.75 from -2.25 to -1.5. This to me seemed strange. I await the glasses but did spend quite a long time switching back and forth to confirm.

Has anyone else found their cylinder decreasing suddenly? I have to say my visual acuity in my right eye is and has always been 6/6 and my left eye has been 6/9 at best but following the latest prescription (pending glasses arrival) I could read the 6/7.5 line with just one letter wrong.

I understand that my issues with vision recently are down to a general increase in normal ageing shortsightedness hence the sphere increase in the prescription but can anyone explain why my left cyl has reduced? Or could it be that previous prescriptions have been wrong and had too high a cyl value for my left eye?

[Lia Williams]

my left eye has been 6/9 at best but following the latest prescription (pending glasses arrival) I could read the 6/7.5 line with just one letter wrong.

My left eye though has a sphere increase of 0.50 from 1.5 to 2.0, and a cylinder decrease (as in less correction) of 0.75 from -2.25 to -1.5. This to me seemed strange. I await the glasses but did spend quite a long time switching back and forth to confirm.

Or could it be that previous prescriptions have been wrong and had too high a cyl value for my left eye?

I doubt if your previous prescription was wrong, just that the new one is a better one. I believe it is quite difficult to prescribe glasses for KC as we give such inconsistent answers to the 'Better or worse?' questions due to our irregular astigmatisms. Hence the need for longer appointments and the need to find someone who understands the answers we give.

Lia

[iwb100]

Thanks. Agree about being harder to prescribe for though I don't think it is really rocket science. At first my glasses were all under strength as I perceived mild ghosting as blur and therefore ended up with specs that didn't really correct my regular non-KC myopia as they minimised ghosting by virtue of not being able to see quite as sharply as I could anyway.

Over the years I've found it easier to give a regular optician the right information. I've been to some who specialise in KC and whilst the initial conversation is easier I'm not convinced they prescribe any better than anyone else as whilst they understand your condition they can't see what your eyes are seeing.

My right has been great and the fact that has been fairly straightforward to achieve 20/20 with has been a blessing. I think the problem with my left is that many opticians simply cannot believe I can see 20/20 in my right with KC using glasses and therefore just accept 6/15 or 6/12 in my left as 'fine considering' and rely on my right to give me pretty damn good vision. I've always felt my left had a little more in it as I've been able twist my glasses and achieve near perfect vision albeit with some mild but noticeable ghosting. Hopefully new glasses will be the answer for my left when they arrive, though so long as vision in my right is the same and they don't give me headaches I won't have many complaints!