Crosslinking (stressed and need reassurance)

[PaulWeston]

I have been reading the experiences of many and the poor vision experienced soon after Crosslinking but I would like to hear more from those who had good vision, had Crosslinking, had poor vision as expected straight after and how their vision is now many, many months afterwards. There are stories days and weeks after an event but I don't hear much 3,6 or 12 months later.
I'm seriously considering Crosslinking (I have booked in with Professor Sunil Shah in the Midlands (UK) mid Nov) as the Keratoconus has been identified recently as progressive (Aug 2011 from a second full scan). They were not able to comment on this progression or to what degree or if it will continue.
I would ideally like to speak with someone and would be so pleased if someone would PM me and I would like to give (or swop) my personal contact details.
I'm 39 (male), so I'm not the typical (20 months ago) recently diagonoised Keratoconus patient.
My vision itself is 20:20 so should I be messing with it and have Crosslinking?
The ghosting I see, can be whole words (fainter) under TV subtitles - when sitting a normal distance of about 3-4 metres from the TV. Or when driving the rear car lights of the car in front can blur down to the road when it's not that close in front. This is when I have my glasses on.
In the evening when watching TV I wear my glasses as normal for distance and I just put up with this ghosting from wearing glasses rather than the effort of putting in contact lenses.
Contact lenses do eliminate almost all of this ghosting by a huge 95%. But my concern is that Keratoconus and this ghosting will worsen beyond the contact lens correction.
I guess if Keratoconus was not get worse I would be happy to get on with my life. But this "what if this ghosting gets worse" hangs over me every minute of the day.

[longhoc]

HI Paul

"To Crosslink or Not" is a huge subject -- and a big decision as you've no doubt realised !

The stand-out thing from your summary was your age. Once of the contraindications from research on the subject is patients being over 40. You're not there yet (!) so it's probably a marginal concern. However, would definitely be the first thing that I'd discuss with the clinician when you are making your decision.

Other factors of key inportance are coreal thickness and "K-Max" or steepness of the cornea.

My favourite "Crosslinking on a page" summary is this: http://eyewiki.aao.org/Corneal_Collagen_Cross-Linking

Have a look if you've got time -- it's well worth reading through the whole lot as it's all there including a good summary of the various studies which have been done. Included in the studies is the effect on best corrected/uncorrected vision post-Crosslinking. An interesting point is the data from those studies. I love data. I'm a bit of a statistical nerd and happy to admit it. With Keratoconus in general -- and Crosslinking in particular -- because of it's rarity, it's so tricky to find really top-quality data on the various in's and out's of treatment options. I say this because, in answer to your main question, which I'll charaterise by saying "if I've got 20/20 now, then could Crosslinking affect that ?" then the answer according to the finding of the studies I've seen is "no, not usually and not to a huge degree. It is also possible to get an improvement in vision".

But, but, but... I'm not at all convinced by the robustness of some of those studies. The FDA Phase III Trial will be the real deal in terms of gold-standard verification of safety and effectiveness. It will also (hopefully) spell out once and for all the contraindications for things like age. Looks like it's maybe 6~9 months away in reporting. Of course, these things can slip... so might be longer.

Sorry, wish I could offer uneqivical reassurance... I always was a bit overly cautious I think so don't let my fretting carry any weight. Anyway, have a read through the link and let us know what you think. Do please post any specific questions you'd like answered. There's also our comprehensive literature and DVDs of conferences where just this sort of thing gets addressed. So don't hesitate to ask if you'd like that too. We do get professionals in the forum so they will be of more help than I if you've got anything you really need a definitive answer on. Would end by saying the best place to get the definitive answers for your specific situation is the person in the clinic you're dealing with -- you've every right to ask for as much information as you need to help you choose. And any decent provider would not mind at all being pestered for all the facts -- or 'fess up if there's some unknowns that no-one can really be exact about.

Best wishes

Chris

[caroline6505]

Hi

Vision in my left eye was 6/12 and my right eye 6/24. Because of the nature of my work (graphic designer) I got to the stage where I was having great difficulty reading text (I work on a lot of books, magazines, etc). I've never been able to tolerate contact lenses after trialling 32 pairs and glasses made absolutely no difference to my vision. Vision in my left eye seemed okay to me, but in my right eye really quite poor – could only really see shapes and colour, but everything was very blurry indeed. I went to see a private specialist at the Centre for Sight where I was recommended to have crosslinking in both eyes an a wedge resection in my right eye. I had crosslinking in my right eye in June and left eye in July. Have to admit that it's really only now that I'm noticing a difference. In fact, at one point, I was actually starting to regret having it done – I had extreme light sensitivity, but it seems that that was more attributable to problems associated with the wedge resection. The procedure itself wasn't nearly as bad as I thought (if you want to know more about that, happy to tell you all about that – let me know) and I didn't suffer at with my right eye, but did after having my left eye done. Had each eye done by different surgeons and the one that made more 'punctures' (spiky gadget called a Daya disruptor, which punctures the epithilium as opposed to scraping it or taking it right off) – I definitely suffered with that one. My eyes were intially very watery and light sensitive. After 2 days minor discomfort (slight gritty feeling) disappeared. With my left eye, it stung for a few days and watered a lot, but that's as bad as it got. Like I say, it's taken since June/July until now for me to feel that my vision has got back to normality. The added bonus is that it has actually improved (recently visited the optician who advised my vision is better now than that of 11 years ago!). Although it should be noted that the sole purpose of crosslinking is to halt progression (surgeons only recommend procedure if there is evidence of progression – there are of course other factors too), but in some cases there's an improvement.

I read up on crosslinking and noted of the data available that there were good results so far in the majority of cases (only debate seems to be on success rates of epi-on versus epi-off). The procedure has also been done over past 13 years in Germany, Europe, and USA, and so long-term results are now starting to filter through. NICE have issued guidelines on procedure, and it's anticipated that it'll be approved fairly soon. In addition, my sister has had corneal transplants in both eyes, which have proved to be unsuccessful and/or nearing end of lifespan. NHS footed the bill to send her to the Centre for Sight as local NHS surgeon botched the job. Having see what my sister's experienced, I therefore had a great deal of faith in the CFS, and decided to go for crosslinking, etc. I couldn't possibly tell you what to do, as I think it's a very personal decision and one needs to research as much as they can, but I guess a lot boils down to confidence in the expertise of their surgeon/specialist.

Best wishes.

Caroline.

[Lynn White]

Hi Paul,

I see a lot of patients with keratoconus in my practice and have this conversation very regularly! To crosslink or not to crosslink is a very interesting question.

As Chris indicated, most of what you describe, your age, your 20/20 vision would suggest "do not do it", as its not necessary..... EXCEPT, you have now shown progression. The lack of comment on whether this will continue or how "bad" it is is perfectly understandable. Why is that?

Well, (and I had this conversation several times in practice yesterday) keratoconus means the corneal structure is weak, so that shape changes are frequent due to maybe nothing more than sleeping face down a few times, getting seriously dehydrated, diet changes, air travel etc. These things only affect normal corneas slightly but they affect keratoconic corneas significantly. In the same vein of warning about investments, these changes can induce steepening as well as flattening, so that sometimes an apparent "progression" may reverse itself a few weeks or months later.

Judging when a shape change turns into a real progression can be tricky and involves taking many pieces of information into account and can often mean several visits to a professional before they can spot a proper pattern.

Having said that, in your case, the fact that you are getting to the age when most KC has stabilised, the fact that it is starting to move has triggered the advice for CXL. There are many documented cases where KC did start to progress at middle age and beyond, bucking the normal trend.

Additionally,the fact that a cornea changes a lot (without necessarily progressing) is itself both a sign of instability and is a real problem if you are trying to lead a normal life, not to mention costly, if you have to keep changing glasses/contact lenses. CXL is a perfectly proper procedure to consider in these situations.

Now, as to long term effects. Chris gives excellent advice as a self admitted stats junkie. The problem with studies and stats, though, is to get a decent prediction of long term effects you have to run them LONG TERM. That means 20 years or more. I really do need to keep saying this because it appears that most people really do not quite understand.

People often jump on new procedures (see the KeraFlex thread) that have been barely out a year and want to know what will happen long term. To be perfectly clear, we cannot say how any procedure will affect you when you reach 70 if you have it when you are 20, if patients have not been followed up for that long.

If you are talking up to a year or more, then I have data having followed post crosslinking patients from around 2004. The vision in the majority of cases returned to at least pre op levels within a few weeks and stayed there or improved slightly thereafter. What changed was the prescription, as the cornea tends to keep changing shape up to around 6 months, very much dependent on the individual cases. These results can also be found in the longer term follow up studies.

However......

Going back to what I was saying about long term studies. When CXL was first started, precisely because long term effects were not known, the procedure was mainly undertaken by people with more advanced conditions or those who had nothing to lose. Some of these corneas were pretty much on their "last legs" anyway. In other cases, some had differing forms of the procedure. (eg "pricking" the cornea, partial epi off etc) This tends to skew long term results and makes it difficult to judge how it will affect corneas that are essentially still fairly normal.

As it has proved to be more and more successful, people with less and less advanced conditions start to consider it and we have to change how we balance the risks. This is exactly the same as any other "new" medical procedure.

With CXL, there is about 1in a 100 chance you can get a scar following the procedure and no-one really quite knows why. In others you may get a haze that tends to persist.This sort of thing is what reduced the vision in the cases I have been following who did not go back to normal within weeks. However, even their vision gradually improved over a year to 18 months.

Finally, as a more general point of view, to others considering CXL, you do need to keep an "eye" on progression. So my CXL rating would be:

1) If you have good vision and quality of life with whatever mode of correction and you are not progressing at all, then CXL is a "back burner" option. Carry on as is until you have some sign of progression.

2) If you have had a change in topography shape but corneal thickness is reasonable (comfortably over 400 microns), wait another 6 months and check topography and thickness again with the caveat that you seek professional advice straight away if you notice significant changes in prescription or vision.

3) If your topography is unstable and your corneal thickness is close to 400, then seriously consider CXL. KC can progress rapidly at times and leave you with a very difficult corneal shape to fit with contact lenses, so that even if you have CXL at this point, you may find it hard to regain the vision you had before.

4) If your corneal thickness is at 400 or just below, CXL can still be done by thickening the cornea with distilled water. At this point, my own personal opinion is that, if it was me, I would have CXL done asap.

Finally, though, some people are constantly stressed by what might happen but have relatively normal corneas. To them, risking any possible long term effects of CXL win out over short term gain in peace of mind.

You see - its really not that simple! Nothing in this life ever is, I am afraid.

Please feel to PM me or contact me by email (see my signature) if you want to discuss anything.

Lynn