Hi there John and welcome to our forum.
Thanks for your post -- which is very welcome as it contains pretty much a definitive list of the sorts of issues that people with Keratoconus have to grapple with !
It is a not infrequent comment that the NHS provision for managing Keratoconus is variable. Often people believe that private practices are the only alternative if they think they've been let down by the NHS. While there are some superb -- world class -- providers, it is good to know that the NHS has many, many centres of excellence. As you say, sometimes though you have to switch around to find one that delivers what you need.
As your son's experience shows, even with bilateral Keratoconus, it is often the case that one eye is worse than the other. This necessitates differing treatment strategies. I take it that the intac option has been ruled out for the left eye due to advanced thinning of the cornea ? (and the same applies to Crosslinking). If this is the situation then you've got -- as it sounds like you, your son and the clinicians have realised -- basically two options. One is to continue to try and get a lens of some type or other to work. The other is a graft.
This decision point is the real hard work for those of us with Keratoconus. Many people luckily never get there -- they manage with lenses, intacs, crosslinking or whatever indefinitely. However, if you are at that point, it's not easy to know what to do for the best. I know, as I've in the past 6 months gone through exactly the same process. And it's then you realise that while the clinicians are as helpful and apply their expertise as well as they possibly can, they can't make this sort of decision for you. Whether it's spelt out or not, you're really a bit on your own.
The way I dealt with the choice was to make 100% certain -- beyond any doubt in my mind -- that I'd genuinely exhausted all possibility of obtaining a lens of some description which I would be happy with. This is where, if I have a criticism of the NHS, it's that typically you get RGP (hard) lenses, they try and produce an acceptable fit, but once you start reporting back that the inevitable compromises in trying to get a "perfect" fit aren't suitable for you, it's then you get told you need a graft. You are quite fortunate to attend a clinic where they offered hybrid type lenses. Many don't.
But there is so much choice in lens types -- apart from hybrids there's also soft lenses for Keratoconus, sclerals (large diameter lenses), semi-sclerals and even within the RGPs, there's several different manufactures offering different variations on the RGP theme. So I do sometimes have a hunch that with some of the less specialised regional centres, you can end up with a false choice between RGPs or maybe hybrids, and a graft. This could leave several potentially good deals on the table that you never get the chance to evaluate. Another point you rightly bring up is solutions and the cleaning regime. It can make a significant impact on lens tolerance and wear times because the products are often profoundly different in composition. For example, the polymer cleaners are quite dis-similar in the way they are formulated to the hydrogen peroxide + neutralising disk systems. You might be sensitive to one, but perfectly happy with the other. Then there are also allergens -- Keratoconus and allergies often go hand-in-hand. The proper management of allergies can also increase how we get on with contact lenses. Working through all these variables is definitely something to consider but it is time-intensive. We're all of limited patience, so how much time is reasonable to throw at the problem of getting on with your lenses ?
For me, I went through every type of lens out there apart from sclerals and gave all of them a fair chance. By "fair chance" I meant at least 6 months+ trials. You really cannot make a proper decision on whether a particular lens type is going to be acceptable to you in the long term in less time than that, in my opinion.
Only after doing that could I say that none of the options short of surgery would be viable for me. That made the decision easy -- well, easier, anyway. I knew that whatever the outcome of the graft, it was the best thing for me to do no matter what.
Does that mean that I think this is what you son should do ? Well, yes and no. Yes because by ruling out all lens types he'll be certain that the graft route genuinely is the right thing to do -- or else he'll have discovered a lens type that is fine for him and meets his needs. But -- and I hate to be contrary but I'm trying to be as honest as I can -- possibly not. Remember when I said above that I'd tried everything apart from scleral lenses ? That's because after far more years than I care to recall, I'd reached the limits of my willingness to go through yet another period of -- often uncomfortable and in some respects debilitating -- trialling lenses. I can totally understand, therefore, why your son may well be thinking "sod this, enough's enough" ! Looking at his age profile, at 23, he may well simply want to just get on with his life and if he's formed the opinion that a graft is the means of achieving this end, then that's what's leading him to consider it.
So, a graft it is then ? Erm, no. Not without a lot of soul-searching. While the outcomes of many people's graft are excellent, some unfortunately aren't. The recovery time is long in terms of getting your final best corrected vision. There's the constant risk of rejection episodes, infection and complications from the immunosuppressant medication. And even when the stiches are removed from the graft (which effectively marks the end of the treatment) the graft remains a weak point as it will never have the integrity of tissue which hasn't been joined in this way.
The best I can suggest in summary is that you and your son get all the facts about all the options, then think everything through. We've got some excellent information (I would say that wouldn't I

) which we can send you if you like. Just ask. Also, the professionals dealing with your son can talk you through things as well. They sometimes are a little slow to volunteer information in my experience (I don't know for sure, but I have a suspicion they don't like being put in the position of making decisions for you), but they are invariably happy to answer factual questions such as providing statistics on graft survivability, mean best corrected vision outcomes and so on.
As I've mentioned, this really isn't at all easy so I've the greatest sympathy for what you and your son are having to deal with.
If there's anything more you need by way of additional information about the points I've raised, do please say.
Best wishes
Chris