Anyone tried corneal refractive therapy (CRT) contacts?

[David]

I was just reading about CRT contacts in popular science. You wear them at night and they correct low to medium nearsightedness while you sleep. They say after a week or two of wearing them, you can go all day without glasses or contacts.

They've been FDA approved since 2002. They not covered by most insurance and cost about $1500 to get started and $300 a year after that.

[Racerbvd]

I haven't triend them, but my eye doctor of over 35 years thinks they are the way to go, so I may give them a shot if I keep putting off the lasic.

[charlesbahn]

Bad idea. These things have been around since the 1960's and they've never worked well long term- and sometimes cause permanent eye damage.

They work by being harder or a different shape than your own cornea to mold it into a new shape. Then, the cornea is supposed to stay that way. Problem is, the cornea doesn't like this and tries to resume it's own shape naturally so that the vision becomes unstable- sometimes taking 6 months to come back to normal, during which time the vision is different in the morning than the afternoon, than the evening. In some cases the cornea responds by causing scarring that causes blindness that can only be corrected by corneal transplantation. That's where I come in. I do the surgery. It's expensive and takes about a year to recover from.

The worst that can happen is that the cornea doesn't get enough oxygen at night through the lens and closed eyelid, becomes swollen and painful, gets infected, and the eye is lost.

[David]

I guess that answers that question.

[jluetjen]

Not so! I've been wearing a CRT lenses for 3 months now and theyre great! They're not for everyone since there are some side-effects, but compared to laser surgery, they may be an ideal alternative for some people (like me).

1) Laser surgery is not slam dunk. Amongst the fine print you'll find the following:
- Scarring. Not a big deal if you have it done once, but if it needs adjustment, the scarring is cumulative. This also doesn't go away.
- If you have dry eyes, laser surgery will make them dryer -- potentially significantly so. This happened to my wife and she now is taking eye drops multiple times a day to keep her eyes moist after having Lasik done a few years ago.

CRT has some different compromises:
1) CRT requires that you wear hard lenses. For the first week or so these will take some acclimation if you were previously used to soft lenses (like I was). They still make me look "tired" when I have them in and I tend to flutter my eyes a bit, but I can read or watch TV before bed time with them in with no issues. The sensitivity has gone away as my lids have developed "callouses" to the hard lenses.

2) If you wear them every night (like you're supposed to), your eyes will stabilize and I don't have any appreciable degredation from morning to night. On one occasion, one of the lenses came adrift overnight and so did not shape my cornea. I could see fine, but by the end of the second day, that eye could not see (by itself) well enough to drive with. But with my corrected eye I was fine. I'm now sensitive to what it feels like if a lens isn't sitting correctly.

3) While the concept of CRT has been around since the 60's, it's only in the last 5-10 years that they have had lens material which had the correct charectoristics to allow them to be safely worn overnight. Apparently it required a couple of flights in the space shuttle to develop the material (although I doubt that shuttle flights are required for the production material). I know that my experience is that the lenses get a little gupey in the mornings (compared to wearing no lenses), but I can still see to get up and walk around and do things. I generally take them out first thing in the morning (~ 4:40) and I can still see fine past 11 with no issues (on those few days when I stay up that late).

In my case, my eyes are not good candidates for laser surgery since my pupil's sizes are at the larger end of the distribution. I also did not use hard lenses which apparently change your lense shape in a different fashion that compromises your eyes for CRT. Not to mention I didn't want to risk the dry eye issues nor having permenant surgery performed on my eyes.

My experience? I could drive the morning after my first night and tested 20/20 (better then most my eye doctor does admit), although my vision wasn't quite right around the pariphery of my field of vision. The second day it was better still. Since then it's improved and the halos that I had around lights at night (also a common side affect of Laser surgery BTW) have progressively gotten better. I've also noticed a greater sensitivity to dust on the lenses with hard lenses compared to soft lenses, so cleanliness is key in your day-to-day mainanance of the lenses.

I do love not having to worry about a contact lens floating out when bike-riding at speed, and being able to see when I swim or water-ski. I also like being able to nod off for a cat-nap when travelling (planes do that to me) without waking up to super sticky eyes and a junked pair of soft lenses. Now if I nod off, I wake up and can see perfectly with no issues.

So in my case, I'm a happy customer and something of a poster child for the process. My wife had laser surgery and is still generally happy with the results in spite of the side affects. So there you go, neither is necessarily better or worse, but rather just a different set of compromises.

[charlesbahn]

3 months does not constitute long term success. You may be lucky, and wear them for many years. But, this is still the same old "orthokeratology" that's been around along time. I've treated many very unhappy patients because of it. It does work initially, but then corneal moulding and instability develope. The ability to wear the contact lenses begins to diminish over time, and the vision becomes more and more variable and unpredictable. It is a gradual process. Many are pleased at the initial success, but I've never seen anyone who could do it for more than a few years. The long term risk for corneal scarring and infections is, in my opinion, higher than with LASIK.

Again, you might be the lucky one. Keep us posted.

[jluetjen]

Charles, you obviously have some background in Optometry -- right? Do you care to share it since the rest of us are mere consumers? Your experience with CRT, does it include the more recent products/processes, or is it based on the processes that date back to the 60's? The reason that I ask is that my (layman's) understanding is that the earlier attempts at CRT (aka: Orthokeratology) were limited by the hard lens material that could only be worn during the day when awake. The current products/process allow the lens to be shaped each night so I would expect the results to be more consistent then if a person was wearing the lenses for a day or two and then skipping a day.

[charlesbahn]

I'm an Ophthalmologist with fellowship training in cornea and glaucoma, which means that I am an MD and surgeon of the eye. I fit contact lenses, and care for contact lens problems, although that is not the primary focus of my practice. I have never fit a patient for CRT, among Ophthalmologists it is considered to be a poor procedure at best. But I have taken care of many patient with corneal molding problems from contacts. The practice of placing a contact lens on the eye that does not fit, to change the shape of the cornea, even with the newer, more oxygen permeable plastics, is mainly an Optometry practice. Most if not all Ophthalmologists consider it questionable if not malpractice.

Corneal molding occurs either intentionally as orthokeratology to change the refraction, or unintentionally in people who wear regular contacts for nearsightedness or farsightedness and just have a bad reaction to the contacts (or the contacts are fit wrong, ie too tight or too loose). Molding can occur with both hard (gas permeable) and soft lenses, regardless of the oxygen permeability of the plastic, although it is more common with the harder plastics (PMMA and gas permeable). Once the corneas become molded, stability and the tendency of the cornea to scar are problems as I stated above.

In my area (DC) I do not know of anyone, even Optometrists, that are promoting this. In my 25 years of working with the cornea, I can't imagine that it is a good thing long term.

But I suppose I could be wrong.

[jluetjen]

OK. Thanks for the extra information. .

- John

[jluetjen]

First off, I'm not nieve (sp?) enough to ignore the fact that many people in this discussion (and by this I mean in the wider world rather then just on this thread, are both pro- and anti- CRT) have agendas. Never-the-less, I waded into google to see what I could turn up.

Doing a Google search turned up the usual sites, many of which I suspect are penned by "supporters" of CRT, but they're interesting none-the-less. It's interesting that the FDA apparently feels that the technology of CRT is significantly different from Orthokeratology and thus shouldn't be labeled with that term. I'm sure many people will point out that the FDA is hardly non-political, so we'll let that go.

I did a search on "corneal refractive therapy Ophthalmologist" to see if many Ophtamologists (I wouldn't even be able to spell the word without your help!) agreed with your conclusions. Apparently this one does not , although I don't know him from Adam, nor what his stake is in the discussion. Another case developed ulcers in children and you can read the conclusions yourself -- they are ambiguous at best, and potentially intentionally so.

The article Orthokeratology: A Heated Debate Continues seems to describe the treatment and the affects in fairly neutral terms, including numbers. I guess it highlights that CRT, like any medical treatment has side-affects and risks. None of it is slam-dunk. So we should all go into it with "eyes wide open" so to speak. 125 Shifter, I'd be interested in what you decide to do and how it works out for you.

[scottmandue]

I an fort nine and my eyesight is slowly getting worse (change in prescription every two to three years) is surgery pointless for me presuming that I would need glasses again in a few years?

[jluetjen]

BTW Charles, I appreciate your insights on this subject. Your thoughts have prompted me to do some additional research on the subject. I'm not returning my CRT lenses, but it's good to be educated about the risks and concerns.

[charlesbahn]

jluetjen- no problem, hope they work out for you.

scottmandue- a lot depends on what your eyeglass prescription is. I am not a great fan of LASIK myself, even though I am a cornea surgeon because of the 2% risk of serious complications and 30% risk of minor complications. Most people who are over 40 are presbyopic and need help with reading. LASIK makes this worse. In general, if you are farsighted (your distance glasses RX starts with a + number) you shouldn't even consider it. If you are nearsighted (your distance glasses Rx starts with a - number), you need to be very aware of how it will effect your reading vision

[Rot 911]

Charles, thanks for bringing your knowledge to the board. As far as the CRT lenses, just that fact that there is a "heated debate" over their use would be enough to keep me from using them.

[jluetjen]

Kurt, from a logic perspective I don't follow you.

If you asked a European, they would tell you that there is a "heated" debate concerning Genetically Engineered (GE) food. What the Europeans consider to be GE Foods have been for sale in the US for years without any clear linkages to any deaths, and for the most part nobody here bats an eye-lash on the subject.

If you asked some Americans, they would say that there is/was a "heated" debate about labeling Allergens in foods -- and as a result Allergens are now labeled on all foods in the US. But that subject doesn't even register on the European's radar screen in spite of there being at least 20 deaths in Norway alone in one of the recent years ( but I no longer have the reference) directly linked to food allergies. (Disclaimer, I have a daughter with food allergies, so I have a stake in this example.)

So the fact that there is a debate doesn't mean that something is dangerous, nor does the lack of a debate (at least in some quarters) constitute a safe situation.

At the end of the day, we all need to make our own decisions, but since you offered up your rational, I have to admit that I don't follow it.

[David]

I'm 39 and nearsighted. I can still read tiny print but it's getting a little blurry. I don't really won't to get lasik and then need reading glasses, so I guess I'll keep wearing glasses and contacts. Besides the only thing that scares me more than spiders is jumping out of a perfectly good airplane and hurting my eyes.