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Post Info TOPIC: Urrez-Sawalij syndrome
Anonymous

Date: Tue Mar 21 10:22 PM, 2006
RE: Urrez-Sawalij syndrome
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Thank you very much for posting Juantion... I feel so glad we have professionals like you who do engage with the issues and go futher than most to do so...


Just some points i wanted to communicate with you if i may...


1) lamellar grafts are a god send and hopfully they will out preform traditional corneal translants in all the key areas including their survival rates... as yet its too early to tell but in theory they should be much better than a traditional transpant.


2) I think the reason x linking and mini-ark (and even Intacs) are better in a lot of ways is due to the mechanical strenghtening of the weakened area which is common to all of these treatments unlike with PK or lamellar graphts, and with intacs its reverable if needed and i guess that, if done early enough then the side effects of contacts can be avoided as well, which do increase the chance of a transplant if the patient if not advised properly with there use.


We can only talk about the available studies with the new and old treatments, where new treatments (routine treatments to some!) do hold promise and the old ones do not, at the moment its what a Dr thinks and where you go to get advice to create more chances for the patient to get out of the medical loop as much as possible. 


Here are two articles... which clearly shows us patients that the head-line figure of a transplant being a success by 96% is mis-leading...


http://www.cornea.org/study_database.html


http://www.emedicine.com/oph/topic90.htm


3) Crosslinking can be done on a transplant, and so hopfully the kc or long term astigmitsum re-turning to the transplant can be halted for people who has had a graft,  so that another transplant is not needed for these people. 


4) If more scleral lenses was given to patients... not only will transplant rate go down, but also the complications of what a flat fitting contact lens does on a weak cornea and so reducing transplant rates that way as well... more people should have access to scleral lenses and at affordable prices.


5) One of the major problems why a corneal transplants takes place is due to contact lens intolerance (which you rightly mention), now the thing is that 60% still need a contact lenses after-wards... and so for contact lens intolerant people having a cornea transplant in the hope they could get back to no glasses wear, or glasses wear is a risky gamble to take, or that there contact lens intolance will be no more is also a very risky gamble to take... thats the trouble...


But there is much more choice now than even a year ago and thats really great to see. 


Anyway thanks for taking part and engaging with us... and also thanks for your efforts in kc to help us like a true professional!


Please tell them all at the meetings about us and what we are trying to do for our brothers and sisters! and also tell them that they are all welcome!  



-- Edited by QuintriX at 02:04, 2006-03-22

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Senior Member

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Posts: 107
Date: Wed Mar 22 6:23 AM, 2006
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what an excellent post!


   we feel so satisfied when a   specialist comes into picture and discusses progress being made in the field . thank you very much sir



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Ophthalmologist

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Posts: 18
Date: Wed Mar 22 4:52 PM, 2006
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Hi again:


Iīve just read the links about corneal graft rejection and i would like to clarify some points.


Corneal graft rejection, which is an immunological attack to the grafted cornea happens between 20 to 30 percent of KERATOCONUS patients. Under appropiate treatment and early diagnosis, 99% of these episodes, that can happen once or rarely twice during the first one or two years post op, are cured, leading to a success rate at 10 years for KERATOCONUS patients ( donīt include other corneal causes of grafting with poorer prognosis in these numbers as I see included in the links) of around 96 %.


If we put all the corneal grafts in the same bag, of course the survival rate drops to 65%, and I can tell you that the survival rate for corneal grafts in patients with severe chemical burns, aniridia, severe glaucoma or other pathologies could be as low as 10% at one year. In our experience, keratoconus is the most privileged corneal pathology in corneal transplantation.


In our experience, and i can tell that i see patients grafted 20 to 40 years ago, corneal graft rejection is not the main problem in KC. What we find is long term progressive astigmatism, which is due to recurrence of the pathology in the peripheral cornea, NOT in the graft, and maybe it will be difficult to cross-link this area of the cornea without damaging the limbal area in which are located the stem cells of the corneal epithelium, without causing damage to them. Other problem is long term failures observed due to progressive loss of endothelial cells, which are responsible for the corneal transparency. A normal cornea has between 2000-3000 endothelial cells per sq mm and this count decreases with age. Corneal grafts are performed using tissue with at least 2200 cells per sq mm, but the decline is faster, and ususally after 10 years, the cell population is between 600-1000. In some cases, due to aging, senile cataract develops, and we have to perform cataract surgery, the graft can be affected during the surgery, and a repeated graft is sometimes neccessary.


So the long term survival rate is affected not by the immune system, which is only significant in the first one or two years post op, but other factors like endothelial cell count decrease and refractive problems.


How to solve them? Lamellar surgery preserves the patient's endothelium and long term survival of the recipient's endothelium should be better, so we expect better long terms results with thess types of corneal grafts. Regarding the re-developing of keratoconus in the peripheral cornea, i have no answer yet.


Finally, i hope that new treatments can avoid invasive surgery. This is our goal. But we need more time to settle conclusions about the efficacy of intracorneal segments. I agree that this is a mechanical technique, but  what happens with the biochemical and degenerative processes inside the tissue? The keratoconus appears for some reasons, developing a collagen degeneration with enzymatic and apoptotyc changes. Will a piece of PMMA stop the process in the long term? Cross links increases the strength of the conea increasing the inter fibrillar unions of the collagen, but the keratocytes dissapear in the anterior two thirds of the cornea after the treatment, regrowing again some months later from the peripheral keratocytes, which are the collagen producers. Corneal collagen is renewed in a period of around three years. Are the keratocytes normal or abnormal again? Is the renewed collagen normal or abnormal again?


As you see there are many unsolved issues that are yet to be answered but we need long time. I am glad to see these new emerging techniques that benefit our patients avoiding corneal grafting or at least delaying it. As i said in my post, early diagnosis makes early treatment and better long time results. But there are still cases in which corneal graft is the only solution to restore sight.


 



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Juan
Anonymous

Date: Wed Mar 22 6:52 PM, 2006
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Hi Juanito,


Yes its all for the future (its not going to happen over night) but instead of having a mission to find a "cure"... which i think even common conditions or illness's don't have much of!... something that "works" is enough, and we are following progress and some Dr's actually thinks of crosslinking as a "routine" treatment to offer those newly diagnosed, and also that it is a "sin" if they are not offered it... because they have more experiance and knowledge about it as they have been doing this treatment for longer... and things need to start somewhere... most of the time kc specialists think contacts lenses and transplants are ok ... so whats the point to look in to new treatments... which means new treatments stay as new treatments for longer than need to... its the forward thinking ones who working closely have tried to benfit from new treatment in this generation...


There are, in practice, so many countries embarking on or using crosslinking, recently its been approved by the ethics committee of the uk, I personally know four doctors in the Uk (two offering it, and two going to offer it) working with crosslinking, and not forgetting the longest follow up being eight years with out problems and in all studies kc was stopped.


They have done many years of exhaustive animal testing which is why since 1994 crosslinking has been available for patients. These are not just Dr's but scientists that have done the testing and from which for many years Dr's have been doing this treatment for patients to benefit from, with all all the checks and balances been done to get to that stage, for them to he happy. New Dr's to this like you will ask the obvious, which has been asked already, many many years ago and this is why i tell you this.


The keratocytes "disapear" or run away in any form of eye injury, this includes in a corneal transplant, but they return always.


All these things have been worked through by scientists after many years of testing and dupilcating the same results. 


The 96% success of grafts is everywhere "advertising"... its not seen like this from a patients prespective, if its that good then whats the problen in kc?... i've heard of people being told to do a transplant before their insurance runs out!... its things like this which people need to be aware off... so the actually need for a corneal graft is lower than one in five, when with the right advice that figuare could easily be lower... for example Italy has the highest rate per capita in transplants... the only reason is because scleral lenses are not used...


Btw... what do you think of mini-ark? I forgot to ask in my last post...


All the best and thanks for posting.



-- Edited by QuintriX at 04:24, 2006-03-25

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Ophthalmologist

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Posts: 18
Date: Fri Jul 6 5:52 PM, 2007
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Dear anonimous:

I would like to clarify some of the points you posted:

1.- Lamelllar grafts ( DALK). Itęs true that you donęt transplant the endothelium so the chance of rejection is much lower tha with PK. But a "god send"???? The technique also have some problems to be solved yet:


a) Thereęs a chance of perforating the endothelium during surgery even in the best hands that makes the surgeon convert to PK. The last article published shows 7.1 %

1: Cornea. 2007 Jul;26(6):707-8. Simplified technique for deep anterior lamellar keratoplasty.

Parmar P, Salman A, Kalavathy CM, Thomas PA, Jesudasan NC.
From the Institute of Ophthalmology, Joseph Eye Hospital, Tiruchirapalli, India.
PURPOSE:: To describe a new technique for performing deep anterior lamellar keratoplasty (DALK) that can be done without special instruments and where deep stromal dissection can be performed under direct visualization. METHODS:: In this prospective, noncomparative case series, DALK was performed by first creating a scleral pocket incision to initiate corneal dissection and continuing further dissection under direct visualization after partial trephination. Fourteen eyes of 13 patients with corneal pathology not involving endothelium were operated on by using the new technique. RESULTS:: Accidental entry into the anterior chamber occurred in only 1 eye (7.1%). After a mean follow-up of 10.3 +/- 4 months, the graft was clear in 12 eyes (92.3%), and all 12 eyes had a best-corrected visual acuity of 20/60 or better at this time. CONCLUSIONS:: Our technique for DALK offers an alternative to the currently used techniques.
PMID: 17592321 [PubMed - in process]

b) If you leave more than 20 microns of corneal stroma over the descemetęs membrane the visual acuity of the patients is very poor due to the scarring in this interface and optical aberrations are present in this cases. And I as a surgeon can tell you that even with the new femtosecond laser technology we cannot ensure to all the patients a perfect interface. Here you have the last paper.

1: Am J Ophthalmol. 2007 Feb;143(2):228-235. Epub 2006 Nov 30. Links
Quality of vision and graft thickness in deep anterior lamellar and penetrating corneal allografts.

Ardjomand N, Hau S, McAlister JC, Bunce C, Galaretta D, Tuft SJ, Larkin DF.
Cornea and External Diseases Service, Moorfields Eye Hospital, London, United Kingdom. navid.ardjomand@meduni-graz.at
PURPOSE: To compare visual function after deep anterior lamellar keratoplasty (DALK) with visual function after penetrating keratoplasty (PK) for keratoconus and correlate this with corneal thickness. DESIGN: Retrospective case series. METHODS: Twenty-three patients (32 eyes) with unilateral or bilateral DALK or PK for keratoconus were analyzed for visual quality after suture removal. Evaluation included measurement of visual acuity, contrast sensitivity, and higher order aberrations (HOAs) (WaveScan; Visx, Santa Clara, California, USA). Readings were performed with both spectacle and rigid contact lens correction of refractive error. Total and residual stromal thickness after DALK was measured using optical coherence tomography (OCT) and correlated to visual quality. RESULTS: Eyes after PK had better visual acuity than eyes after DALK (P = .018). Subgroup analysis of DALK eyes revealed that the level of visual acuity was related to the thickness of residual recipient corneal stroma. Eyes with a recipient corneal bed thickness of 80 microm had a significantly reduced visual acuity (P = .0009). Contrast sensitivity was similar in DALK and PK eyes. There was no significant difference in HOAs between eyes with DALK or PK. CONCLUSIONS: These data suggest that the main parameter for good visual function after DALK for keratoconus is the thickness of residual recipient stromal bed. An eye with a DALK with a residual bed of PMID: 17258522 [PubMed - indexed for MEDLINE]


c) Endothelial cell count also decreases around 10% due to the surgical trauma, so you donęt preserve TOTALLY the patientęs endothelium. Itęs really much better this technique for endothelial survival than PK, of course. Here you have the last paper.

1: Am J Ophthalmol. 2007 Jan;143(1):117-124. Epub 2006 Oct 20. Links
Clinical outcomes after deep anterior lamellar keratoplasty using the big-bubble technique in patients with keratoconus.

Fontana L, Parente G, Tassinari G.
Unitą Operativa di Oculistica, Ospedale Maggiore, Largo Nigrisoli 2, 40133 Bologna, Italy. luigi.fontana@ausl.bologna.it
PURPOSE: To report clinical outcomes of deep anterior lamellar keratoplasty (DALK) using the big-bubble technique in patients with keratoconus. DESIGN: Prospective noncomparative interventional study. METHODS: Setting: Single hospital. Patients: Eighty-one unselected consecutive patients with moderate to advanced keratoconus intolerant to contact lenses and with poor spectacle-corrected visual acuity. Intervention: DALK big-bubble technique. Main Outcome Measures: Intraoperative and postoperative complications, postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, corneal topography, and endothelial cell density. RESULTS: Seventy-eight procedures (96%) were completed as DALK. Big-bubble was achieved in 50 cases (64%); 28 (36%) required manual intrastromal dissection. Intraoperative microperforations occurred in 11 cases (13%). Baseline mean uncorrected visual acuity was 20/500 and 20/60 two years after surgery. Average preoperative BSCVA, was 20/100 and 20/30 at the end of follow-up. Final BSCVA was better in patients in whom big-bubble with exposure of the Descemet membrane was achieved (P

So DALK is a very good technique, that can be indicated in the majority of KC patients except in cases with a very scarred conus with descemetęs breaks or hydrops scarring in which is much difficult to perform and the risk of perforation is high. But we expect to simplify and improve the actual ways to perform this surgery to allow all the surgeons to do it easily.


2.- I totally disagree with you when you say mini RK strenghtens the cornea. It weakens the cornea by cutting the corneal lamellae inducing a flattenning effect in the center which corrects myopia and astigmatism induced by the KC disease. Thatęs how it works and we know from the experience with RK that changes in refraction due to this weakening effect start to increase 10 years after the procedure!!! On the other hand cross linking really increases the corneal rigidity and hysteresis, and is nowadays the best option to stop the KC in young patients with a progressive disease, but not the mini RK.

3.- Read carefully the links you post before making conclusions. The two citations you link the forum readers are survival rates for all the penetrating keratoplasty patients, operated because a lot of different corneal diseases, NOT ONLY FOR THE KERATOCONUS patients, in which survival, which means transparency, of the grafts is much higher. Sorry.


4.- Ięm performing cross linking and i wonęt never do a cross linking on a graft bec if the KC recurs, itęs not in the graft but in the graft-host junction in which the patientęs collagen weakens over time creating a recurrence of the astigmatism and should be treated with wedge resections and not with cross linking. There are a very few cases of true recurrences in the graft because the donor cornea had previously undiagnosed keratoconus. Thatęs why we are routinely performing keratometry in all the corneas processed in the eye bank, in order to discard donor eyes with KC, LASIK or PRK.


5.- They way we have to go, until we find a genetic or cellular cure to the disease, is to diagnose the KC as soon as possible, performing topography to children if they start with refractive changes in teen ages. Then cross link their corneas trying to stop KC progrssion. I hope we will save a lot of corneal grafts for our kids. Our experience with intracorneal rings is good but the results in terms of Visual Acuity are not still perfect.

So letęs continue working and taking the best of old and new techniques to help our patients, bec the treatment of an individual case is not always the same. Each patient is a whole world and the work of a physician is to offer every patient the better solution for itęs individul case.


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Juan


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Date: Fri Jul 6 6:47 PM, 2007
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juan, i've just read through this topic and found it really interesting as i've had a pk on my left and a dalk on my right, you said that when kc returns in a pk graft it can be treated with a segment being replaced do you mean epikerotoplasty (sorry for the bad spelling) or is it a different technique? Also in your last post you say that young teens with progressing kc should be cross linked, i totally agree with this and wish that this was the view of all of our eye professionals!
As others have said it's sad to hear your son has kc but obviously with you being his farther he couldn't be in better care as you will understand it fully and make sure he gets the best treatment and contacts.
I've been told i'm developing a cataract in my left eye (pk graft in 2004) i have had problems with glaucoma in the past in this eye as a result of steroid drops or is it urrez sawalij synd. Please next time you post could you give an honest opinion of my options if the cataract continues to develop even if i do not use the steroid drops and how this could affect my graft, I've also had tosca enabled lasik on this eye to correct the astigmatism.
Thanks you for all the information you have posted and giving your honest opinion to the board.
tom

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Date: Fri Jul 6 8:47 PM, 2007
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that is amazing, thank you so much for sharing all of that.I feel that it is very comforting to know that KC is becoming so much more aware to people.
I had no idea that Kc could start again on the gradted eye!! good to know
Look forward to hearing from youu again

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Phase Two

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Date: Sun Jul 8 1:53 AM, 2007
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Juanito,

I wish to write a note to you, to say you are wonderful ! I could say it again and again and using all sorts of words, but thank you for taking the time out to tell us what you wanted to say.

To everyone:

1) Before total corneal tissue removel every treatment can and should be lined up (prefferably in series, the least invasive first) and discussed before this happens, because it still can be done after all options have been lined up against it and discussed.

2) Mini-ark is now being done in London (crosslinking can be used to strenghten the cornea in combination with mini-ark), but the mini part of mini ark is what makes it minimal, some kinds of KC do very well, not all KC cases are a candidate (as with all treatments), its just another option, when surgery is looming. Please remember when reading all this we are just covering the news like a news reporter does on the TV news or newspaper.

3) Laser on top of a DALK can be done, as corneal thickness returns after a DALK, correctiing any errors where its possible not to wear contacts or glasses after the DALK. This is possible because in the eventuallity of needing another DALK any time in the future, it can be done with oiut the problems associated with PK Re-Grafting.

God bless... where ever you are!



-- Edited by QuintriX at 21:52, 2007-07-08

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