6 ms·

Corneal surgeon here ! (Note : I never implanted a keratoprosthesis. This is an extremely unfrequent procedure, usually performed by a handful of surgeons in a

by gdebel 6y ago

Corneal surgeon here ! (Note : I never implanted a keratoprosthesis. This is an extremely unfrequent procedure, usually performed by a handful of surgeons in a given country). Some insights about this topic. This looks like a great device (never heard before !). This is a keratoprosthesis, meaning this is a last recourse, "no-hope-except-maybe-that", procedure. However it looks infinitely more simple and respectful of the eye integrity than current keratoprosthesis, and, if it really acts like a scaffold for native corneal cells and allows a colonization and the obtention of a satisfying corneal surface, it could be a game changer. It is way too soon to know. A significant percentage (I would say around 40-70%, depending on the country) of corneal graft indications originates from pathologies coming from the inner layer of the cornea (corneal endothelium). Posterior lamellar graft (DMEK) allows today to change only the thin cellular layer which is pathological, with an usually quick recovery. Even the best performing keratoprosthesis won't replace this procedure, because we care to preserve the eye's integrity as much as we can. It is interesting to remember that corneal transplantation is a very special topic because the cornea is not vascularized, meaning less rejection. There still is, of course, but the outcomes as usually good. Keratoprosthesis are today indicated when previous grafts where rejected, when the other structures of the eye are healthy, and when the vision is extremely low. This allows to gain a few years of very low vision before, usually, losing the eye due to infection or high ocular pressure. The technology presented has the potential: - to replace current keratoprosthesis and lower the threshold to decide to perform the procedure : yes, almost sure if the device is well-tolerated - to replace perforating keratoplasty (full corneal replacement, unfrequent today) where the cornea is damaged in its entirety: maybe, highly uncertain for the moment. That would be an incredible step forward, a revolution in our practice. - to replace anterior lamellar keratoplasty, where the anterior wall of the cornea is replaced : highly unlikely - to replace posterior lamellar keratoplasty, where the cornea lacks transparency because of inner layer cellular dysfunction: almost impossible. I would also like to raise awareness on the topic of eye rubbing. The eye surgeon community progressively discovers the highly harmful consequences of vigorous and daily eye rubbing. A few teams (mine, notably) even think that it is the single trigger for keratoconus. You will find a nice illustrations of what a rubbed eye looks like in MRI I by googling "don't rub your eye" (this is me in the MRI ;-) and more explanations here : https://defeatkeratoconus.com/ https://defeatkeratoconus.com/

mkl 6y ago
I would like to second the eye rubbing awareness. I have keratoconus in both eyes, and had two (donor) corneal transplants in the 1990s, in my teens. Even with them, my sight is not great, as the distortions from the transplant scarring and residual keratoconus around the edges are only partially correctable with regular glasses lenses (I think these artificial corneas would not be better). I had bad hayfever as a kid (and still do sometimes now) and rubbed my eyes a lot. I now think it's the most likely cause. Don't let your kids rub their eyes!
- EvanAnderson 6y ago
  I am in a similar boat-- fairly bad animal allergies and hay fever as a child accompanied with frequent and vigorous eye rubbing and now keratoconus (though, fortunately, not so far-progressed as to need corneal transplants). My daughter has the same characteristic long eyelashes that I do, and exhibits allergies (though much less severe than mine). My wife and I have made a very strong effort to prevent her from eye-rubbing. She's old enough now to understand why we were so adamant about it. I'm seeing elsewhere in this thread that nocturnal eye rubbing can be a problem. I never thought about that and it's a bit disturbing. I do remember waking-up with my eyes plastered shut with hardened mucus as a child.
Aerroon 6y ago
Interesting! How much eye rubbing are we talking about? Several times a day? Once a day? Once a week? Any tips on stopping the habit?
- gdebel 6y ago
  To start with, full disclosure : this is a controversial topic. The majority of eye surgeons are still convinced that there is a genetic predisposition to keratoconus, and that eye rubbing is an optional trigger. Other (a growing number) think that this is the sole responsible of keratoconus. My mentor is the main proponent of the eye rubbing theory. I was a skeptic, and became convinced by learning with him how to properly interview patients on this subject, how to prevent eye rubbing, and by seeing the absence of progression after full awareness of the patients (without cross-linking. We don't do any CXL in my department, ever. KC screening and care is one of our main activity: not doing CXL is a financial loss). My mentor's website : https://www.gatinel.com/recherche-formation/keratocone-2/no-rub-no-cone-the-keratoconus-conjecture/ https://www.gatinel.com/recherche-formation/keratocone-2/no-... (No conflict of interest except loyalty). The main difficulty is that it is almost impossible to design an experiment to prove the theory (if someone has a genius idea, please don't hesitate). Usually other surgeons or students become convinced after visiting the department and spread the good practices back home : still a long way to go. The harmful eye rubbing is made with the hard parts of the hand (knuckles). It is frequently nocturnal and almost everytime ignored. Awareness comes when the patient has been informed and told to look for this habit. At the second consultation, the eye rubbing is reported in the vast majority of cases. I count the keratoconus patients that deny eye rubbing after 2-3 consultations on one hand. We prescribe a transparent eye shell to sleep with when the patient denies eye rubbing : it allows them to realize that they rub during the night. We prescribe eye drops to ease the eye irritation which triggers rubbing, and instruct to rub the inner part of the eyelid, against the nose (no eye deformation) if necessary. Sleep position is frequently pathological too (eye vs hand or arm contact. In those cases the KC is very asymetrical). Doctors in our team can predict the eye rubbing habit frequency and intensity by looking at a corneal topography. It is incredible that the role of this habit was ignored so long. I suppose that we doctors don't talk enough with our patients. The financial incentive of performing CXL and surgeries is so clearly detrimental the the adoption of those practices.

by gdebel 6y ago

mkl 6y ago

I would like to second the eye rubbing awareness. I have keratoconus in both eyes, and had two (donor) corneal transplants in the 1990s, in my teens. Even with them, my sight is not great, as the distortions from the transplant scarring and residual keratoconus around the edges are only partially correctable with regular glasses lenses (I think these artificial corneas would not be better). I had bad hayfever as a kid (and still do sometimes now) and rubbed my eyes a lot. I now think it's the most likely cause. Don't let your kids rub their eyes!

EvanAnderson 6y ago
I am in a similar boat-- fairly bad animal allergies and hay fever as a child accompanied with frequent and vigorous eye rubbing and now keratoconus (though, fortunately, not so far-progressed as to need corneal transplants). My daughter has the same characteristic long eyelashes that I do, and exhibits allergies (though much less severe than mine). My wife and I have made a very strong effort to prevent her from eye-rubbing. She's old enough now to understand why we were so adamant about it. I'm seeing elsewhere in this thread that nocturnal eye rubbing can be a problem. I never thought about that and it's a bit disturbing. I do remember waking-up with my eyes plastered shut with hardened mucus as a child.

Aerroon 6y ago

Interesting! How much eye rubbing are we talking about? Several times a day? Once a day? Once a week? Any tips on stopping the habit?

gdebel 6y ago
To start with, full disclosure : this is a controversial topic. The majority of eye surgeons are still convinced that there is a genetic predisposition to keratoconus, and that eye rubbing is an optional trigger. Other (a growing number) think that this is the sole responsible of keratoconus. My mentor is the main proponent of the eye rubbing theory. I was a skeptic, and became convinced by learning with him how to properly interview patients on this subject, how to prevent eye rubbing, and by seeing the absence of progression after full awareness of the patients (without cross-linking. We don't do any CXL in my department, ever. KC screening and care is one of our main activity: not doing CXL is a financial loss). My mentor's website : https://www.gatinel.com/recherche-formation/keratocone-2/no-rub-no-cone-the-keratoconus-conjecture/ https://www.gatinel.com/recherche-formation/keratocone-2/no-... (No conflict of interest except loyalty). The main difficulty is that it is almost impossible to design an experiment to prove the theory (if someone has a genius idea, please don't hesitate). Usually other surgeons or students become convinced after visiting the department and spread the good practices back home : still a long way to go. The harmful eye rubbing is made with the hard parts of the hand (knuckles). It is frequently nocturnal and almost everytime ignored. Awareness comes when the patient has been informed and told to look for this habit. At the second consultation, the eye rubbing is reported in the vast majority of cases. I count the keratoconus patients that deny eye rubbing after 2-3 consultations on one hand. We prescribe a transparent eye shell to sleep with when the patient denies eye rubbing : it allows them to realize that they rub during the night. We prescribe eye drops to ease the eye irritation which triggers rubbing, and instruct to rub the inner part of the eyelid, against the nose (no eye deformation) if necessary. Sleep position is frequently pathological too (eye vs hand or arm contact. In those cases the KC is very asymetrical). Doctors in our team can predict the eye rubbing habit frequency and intensity by looking at a corneal topography. It is incredible that the role of this habit was ignored so long. I suppose that we doctors don't talk enough with our patients. The financial incentive of performing CXL and surgeries is so clearly detrimental the the adoption of those practices.