How is my eye prescription?

[Joe Bloggs]

Currently I have KC but have been using toric soft lenses fine and have been coping as expected with it well minus the odd day of abrasions, red eyes etc.

I dont really know how bad/good my eyesight is without contacts so could someone tell me? my prescription is:

Right eye :
sphere +0.50
cyl -1.25
axis 90


Left eye:
sphere +0.50
cyl -1.25
axis 95

[Andrew MacLean]

Joe

I'm afraid I'm like you: I look at the prescriptions I get from the optometrist, and I haven't a clue what they mean. Why not ask, next time you have a consultation with the optometrist, for an explanation? Then, you can let us know!

Andrew

[GarethB]

There is another factor and that is how does the KC affect your daily life?#

My KC means without lenses I can't see the eye chart but it does not really affect my daily life if uncorrected as I have learnt to adapt. OK I am unable to drive to work and that is where I have issues as my job as it stands at the moemnt makes home working hard as I don't have a laboratory in my shed! The recent job change however will make home working more of a viable option as it will be very desk orientated which is something I can do fine without lenses.

[Matthew_]

where I have issues as my job as it stands at the moemnt makes home working hard as I don't have a laboratory in my shed

Well, why ever not? Can't you Argos for one? Glad you are getting a job which will be less problematic and I hope you are enjoying it, Gareth.

As for eye prescription deciphering, I am useless I am afraid, I keep getting it explained, then forget!

[rosemary johnson]

Hi, and welcome.
This really needs someone like Lynn to answer - and didn't she write a FAQ on this once???
AIUI, until a proper expert comes by:
The "sphere" is the measure of how short or long-sighted overall the eye is - measured in a unit called Dioptres. A + value is long-sighted.
The cylinder is a measure of astigmatism, but I can't remember what the numbers means. Astigmatism is to do with the eyeball being "rugby ball" wather than football ball shaped. If you've ever been asked to look at something like a stylised hedgehog and asked where the spines look further apart, that's an astigmatism test.
Axis is to do with the off-centredness of the rugbby all, or whether the hedgehog spines look furthe rapart at 2 o'clock, 10 o'clock of where.
YOur prescription sounds likeyou are slightly long-sighted, with -1.25 of astigmatism at the angles specified (in degrees, IIRR).
For comparison - my post-graft eye is (or was when last measured) -9 on one axis and -14 on the other, but I don't know how this relates to actual cylinder and axis figures.
In practical terms, I'm very short-sighted - and if I look atsomething like a crossword or sudoku grid, the vertical lines are in focus at about 6" and the horizontal lines at about 4".
I'd suggest - if you're doing OK in the soft lenses, stick to them.
Rosemary

[Joe Bloggs]

These soft torics im currently using have given me close to the vision i was getting with gas permeables. I can read the second from bottom line with them on that letter chart. Probably not as good as RGPs but definately not far off and way better than glasses still. RGP's were just way to uncomfatable (tried them for 6 months) had all sorts of issues with them, the worst waking up with horrible pain in both eyes even though i didnt have them in!.

Also I was wondering, when you guys go to sleep and close your eyes isnt there a slight soreness and little pain in the center. Its only really noticeable when the eyelids close as they create a fricition between the eyeball. I do wear my contacts about 16 hours a day though. Dont have any rest days either :p
No problems so far apart from one or two occasions where the contacts ripped while they were in my eye! and had an abrasion once.

Yeah if Lynn could help with my prescription that would be great.

[GarethB]

Joe,

Soreness when lenses out sounds like there is something not quite right and you could be over wearing the lenses.

Discomfort is the bodys way of telling you something isn't right. It might be worth gettinging it checked out before the soreness gets worse. It might be a simple case of eye drops to help the eye stop drying out as many of us have poor quality tears which is made worse by contact lens wear. Best to play it safe.

I did and have found I have an allergy to something, don't know what as it is still being investigated but at least we can treat the symptoms and my lemns wear is increasing again. It did drop from 16 hours to 2 hours and I did take rest days.

The allergy was not discovered until after several visits to the hospital, another optom and my GP by which time my work situation was bady affected and all I'd done was try and work through the problem for a couple of weeks thinking I might just be coming down with a cold. That was over three months ago and only now am I getting back to some semblance of normality.

My case may well be very different to yours and be the extreme but only put it here as an example of what can happen.

[Lynn White]

Hi Joe...

Here I am -better late than never

Right... actually, your prescription is very interesting as it is quite low. Normally, people with significant keratoconus have prescriptions like -10.00/-4.00 x 65 - much higher "numbers".

What your prescription says to me is that you may have a KC variation called PMD - Pellucid Marginal Degeneration. This is supposed to be really rare BUT it may well be that it is just harder to detect.

To see what I mean... look at this page I have set up showing different KC corneas.. The top right one shows "upside down" PMD as the steepness, the red part, is usually at the bottom. The blue sections represent flatter areas and typically a patient would have a prescription very close to yours. The central cornea is actually quite normal which is why people can get on with a normal soft lens.

I am seeing a LOT of people with PMD nowadays. In fact, when I was trying to get people for clinical trials of the KeraSoft lens, many were PMD. All showed difficulty getting on with KC RGPs - not surprising, as the central cornea in PMD can be much flatter than normal, never mind flatter than KC!

In your case, the part of the prescription that gives the astigmatism axis as 90 (this refers to the angle your astigmatism is at) shows that the flattest part of your cornea is the same as the picture I referred you to above. That is, you have a vertical flat area above and below the mid line.

Typically, people with this sort of KC tend to suffer a lot of ghosting and shadowing that they eventually get used to.

Hope this all helps but if I have now totally confused you.... you shout out and I will try and explain better!

Lynn

[Joe Bloggs]

Thanks for your help Lynn

[mattjbelfield]

My prescription sounds very similar. Do I have PMD? Must ask my optician. I've had about four changes of Torics in the past twelve months - I've been experiencing problems that are to do with the lens manufacturer changing the material of the Toric lens - without telling anyone! My current prescription is:

Right eye (KC)
SPH + 0.50, CYL -1.75, AX 020
Left eye (astigmatic)
SPH +1.50, CYL -2.25, AX 090

Previous prescription:

Right eye
SPH - 1.25, CYL - 1.25, AX 170
Left eye
SPH - 0.25, CYL - 0.75, AX 060

Prior to that:

Right eye
SPH 0.00, CYL - 1.25, AX 170
Left eye
SPH - 0.25, CYL - 1.75, AX 090

I've often wondered if there's any connection with diet, etc? Is there anything that a KC sufferer can take take to help?

Matt.