UK Keratoconus Self-Help and Support Association

Hi everyone,

I thought I would put up a discussion thread on CXL as its a bit difficult when people come on with personal questions if we all hijack their thread.

So just to start off: CXL has been around for over 11 years. It was started in Germany and studies have been over a period of 8 years or so now. It is basically treating the eye with UV exposure, enhanced by the application of Riboflavin drops. What this does is strengthen the links between collagen fibres in the cornea.. hence the name Corneal Cross(X) Linking. This causes the cornea to stiffen up and resist the deformation that happens with KC. In fact the cornea undergoes natural CXL with age, so one could say that its a natural effect induced earlier than nature intended.

Several questions are raised by CXL:

Does it last?

Is it safe? What are the risks?

Who should have it?

How long should we wait to see if it IS safe?

All good questions. So far, studies show that it appears to stop progression in its tracks. The risks come from the exposure to UV which is why a minimum thickness of 400 is needed. Thinner than this, the UV could affect ocular structures. Above this thickness, the UV should not affect the eye structures - and indeed many people in tropical climates who don't wear shades get a good deal more UV than this. On the other hand, they don't quite get this much this close to the eye - though we have yet to hear of any adverse effects from the procedure.

The big question is: when should one have it done?

This can depend on where you live. in the UK, we are lucky to have a myriad of options and easy access to NHS CL clinics. Before some of you tell me its not that simple, yes, I know it can be difficult BUT in other countries KCers are not so fortunate and corneal grafting in particular is a thorny issue. Most people outside the UK have to pay for their grafts. Some countries simply don't have eye banks - others, say in Africa, have HIV problems so that grafting is very expensive. This means that letting your KC go to grafting stage is not an option because if you are CL intolerant, you have no chance at useful vision.

Thus, in many countries such as Greece and Syria, CXL is already seen as the way to go. In fact, the procedures are quite often: intacs/CXL/ phakic implant/lasik. Thats right... lasik on TOP of CXL! This is something I am not quite comfortable with on a KC eye...but that is my personal belief.

So.... if CXL can halt KC in its tracks.. and the research seems to point that way .... when should you have it done?

Logically, if you follow all the arguments through, it should be done as soon as you have diagnosis. That would give maximum chance of having normal vision with glasses. However, life isn't like that. Most people would want to hang on to see if they were progressing or not. Some would hang on until its almost too late and indeed some do leave it to the extent it IS too late.

Some professionals say: Lets see how it pans out in the future. Give it some time. I usually am in this group, I must admit. Any new procedure, any new drug - its a wait and see scenario as far as I am concerned. Yet.... with CXL I think its slightly different in that we DO know what will happen if you don't do it. There WILL be progression, there COULD be central scarring from hydrops, there will most likely be times of CL intolerance. How long do we wait to see if its ok?

I hereby throw this open to debate! I hope some professionals also come on here and have their say. Anyone who has had the procedure - were you glad you did or not?

Lynn

The other consideration is: how many of the people who have had, or in future may have, CXL would never have progressed very far anyway.
Not everyone goes on to develop "advanced" or extreme KC. Making CXL into the routine means the chances of "doing" lots of peple whose KC wouldn't have progressed anyway.
SO they're being exposed to the risks - or the UV, yes; also from having the top layer of cornea scraped off; of possible adverse reactions to any anaesthetics or sedatives used or even any of the eye drops. And also to the disruption in needing time off work/studies/life - and some personnel departments are less sympathetic and helpful than others, despite the DDA or equivalents across the EU. And pain - I think cclman will remember the posts he wrote about pain.
Do we know how many people there are out there who have a low level of KC who never progress tot he extreme levels?
- I think not, but it seems we are identifying more of them these days.
Oh, if only we had a crystal ball, and could say: "Ah! Yours is likely to progress a long way indeed; you should definitely think about this" or "Yours is not going to get much further than it is now, so it's probably not worth your while"!!!!
Rosemary

Lynn, thank you for starting this.
I can post my story.

I am 24. I have this since I was 16. I did the crosslinking 6 months ago with PRK. PRK was performed just before the crosslinking (so than no crosslinked tissue
gets off).

My k-readings before the operation were:
Right Eye Left Eye
K1 52.1 53.8
K2 60.2 57.1

3 months after the PRK+crosslinking
Right Eye Left Eye
K1 49.1 52
K2 55.6 55.6

6 months after the PRK+crosslinking
Right Eye Left Eye
K1 48.8 52.4
K2 55.3 55.1

This was the technical part. Now,about my vision.

Before the operation my right eye was much worse than the left one. I used to wear soft toric lenses but the vision became so bad that I had
to get something else. My vision with the lenses was less than the driving standards (50% here in Greece).

Now, after the operation, I am able to wear daily soft contact lenses and I get a 75-80% vision (I don't know the corresponding Snellen chart readings).
The main difference for me has been the quality of vision, I think I have a much better contrast and I can try soft lenses that is the best. I am also thinking of the kerasoft3 lenses as well as the iZon glasses (Has anybody tried these?).

The paradox is that my right eye that was much worse before the operation now is much better than the left one.

I can say that it was the best decision for me, even with the prk combination because there is a huge change in my vision. My only concern is the pachymetry
(I had 460μm at thinnest local and now it's 340μm, though the doctor said that there is some kind of flap and that this should increase) and whether this will
last for ever or not.

I don't know about any late side effects but I think I need more my vision now that I am 24 than when I will be 50 or 60.

@Rosemary: You are right in general. Noone knows whether this situation will get worse or not but, in my case, there was a rapid deterioration in just 2 years, so why wait and not take the risk? The chances are far better for the CXL. In my opinion, if there is a deterioration, this should be done. I'm sorry I haven't done this before.

As you may have seen my diary on the forum, yours truly- had ccl/cxl done in Sept. I went back 2 weeks ago for an eye test for new glasses. I now have new glasses and they eyes seem worse than before the ccl/cxl. The doc said they will need time to settle, I go back in Feb 09. The right eye is worse then the left. He said he may put a ring in the right eye. I was also thinking it may be possible to have soft contact lenses later I am not sold on ccl/cxl 100% as I am sure it helps but my opinion is - what the hell if it can stop it why not!! What I did find odd is I'm 42 when I went to the clinic to have it done I was not asked my age. If you read the "blurb" on ccl/cxl it says in the UK they the upper age limit is 40, (I had it done in the Czech Repulic). I'm told I look young for my age- but I should have been asked. They say the upper age limit is 40 because the corneas naturally thicken when you are over 40 or at 40.

I was "off games" as they say, for 4 weeks after the ccl/cxl and was stuck at home in sun glasses all day it was bad as a layer of cornea is scraped off..... Ow it hurt but its early days to right off ccl/cxl at this stage it may be a "magic bullet" to stop it in its tracks from getting worse

P.S I must say I am surprised in the 21st century there are not simple drops to halt KC and thicken the cornea but then again research is so badly underfunded in all areas of medicine.... so why should I be surprised you could say the same for many conditions that people have to suffer. Some clever guy/lady will invent something.... but when and where- who knows

Interesting debate! You say, Lynn, that we know KC will progress. But as Rosemary says, do we? I certainly know people with KC that hasn't progressed (although they're not the ones that post on this forum, or even know it exists!) And we know that more 'subclinical' KC is being identified in laser clinics - is this type of KC going to progress? So there is an argument for saying 'if it ain't broke, don't fix it'. It's good that there is another option out there, and that a number of hospitals in the UK are now doing clinical trials which should lead to it being more readily available here. But I'm not sure everyone with KC should be rushing to have what is still an invasive procedure. And although some people are unlucky in having KC that progresses rapidly, for most any progression takes years (and may stabilise) so the need to act quickly may not be factor for that group. Oh for that crystal ball!
Anne

No dissrespect to any eye doctor or optician/specialist- but they can't commit to ccl/cxl just yet and say it def does stop it progessing as they could shoot themselves in the foot or both feet. Its better for them to say that "it may stop it" but it "may not stop it"! that way all angle's are covered and no feet will be shot. Until its been proved over a 15 to 20 year period on different stages of KC, on different ages of KC and internationally, it may not be possible to stamp it as passed .......I still can't belive there are not simple eye drops to heal a cornea and stop KC.... but then again I do like Sci Fi movies who knows one day

Even 20 years would not be long enough in my opinion to say CXL stops KC.

Until CXL came along, many considered grafts to be the nearest thing to a cure and they have beena round for over 100 years but still after nearly 20 years, as far as my consultant is concerned the KC has returned in my right eye. Therefore I am now treated for my right eye as if I have KC and my left as a post graft patient.

Going forward my daughter is booked in to be screened annualy for the signs of KC and based on current information my wife and I have agreed that once she shows signs of KC then we will get her treated with the CXL procedure.

My consultant told me that in the majority of cases vision improves after CXL, so KC is not only stopped but reversed, it has to be done early enough for this to happen and that the treatment is not as invasive as compared to even wearing RGPs and we are not even talking about other corneal surgery in comparison. All other treatments just "masks" KC when CXL is the only one which treats the condition by strengthening the cornea. Also that its approved through-out Europe.

pepepepe wrote:My consultant told me that in the majority of cases vision improves after CXL, so KC is not only stopped but reversed, it has to be done early enough for this to happen and that the treatment is not as invasive as compared to even wearing RGPs and we are not even talking about other corneal surgery in comparison. All other treatments just "masks" KC when CXL is the only one which treats the condition by strengthening the cornea. Also that its approved through-out Europe.

In my case Im not sure it stopped it or made the eyes better and with new glasses they seem a little worse but perhaps the eyes need time to settle? I think my KC may just stay the same but it had already settled as I'm now 42 and it had not got worse in 2 years prior to the ccl/cxl in Sept this year. I only got the ccl/cxl as a precaution and a hope that it may reverese it a bit!!! I can only hope

Like GarethB said, only after 20 or 30 years we will be sure about the outcome of this procedure.
The same thing happened with lasik. Thousands of people perform lasik nowadays despite this.
There is no procedure without side-effects. This is also true for grafts. You always have the risk
of rejection. So, if you are young or if you do see a progression I can't find a reason to wait 10 years
when it can be too late for cxl. You can easily see an agressive progression in 1 or 2 years and decide
whether it's worth it or not, and if you do cxl, you know that chances are with you. That was my case
and that is why I decided to do this.


@cclman: I have read your post. It's too early to be positive or negative. You have to wait for a semester or a year to see the results.
I'm sure you did what is best.

Lars