Descemets Membrane Endothelial Keratoplasty (DMEK)

[cjkurz]

straikom,

thank you for your comment. i believe melles has published some results from his early cases which showed about 30% detachment rate and about a 30% graft failure rate, so definitely the endothelium is taking a beating while the technique is being refined. however, his articles did suggest that the endothelium may be a little more stout than we thought!

-chris

[straikom]

It is a very interesting technique but it would seem that there will be much more endothelial trauma and loss than with DSAEK. Is there any good data out there on endothelial cell loss or failure rates for DMEK?

[cjkurz]

toval44-

4. i dont know why the graft scrolls so that the endothelium faces out...but guess is that the collagens in descemets membrane contract once it has been freed from the posterior stroma and those linear forces confined to descemet's membrance and unopposed by the cellular endothelium side cause the graft to scroll so that the endothelium is always on the outside of the scroll. that is my best guess, but finding real answer to that question may unlock the door to a simplier DMEK!

[cjkurz]

toval44-

2. trypan helps with visualization of the graft which obviously helps with judging the orientation, so i guess indirectly it does help with orientation.

3. this donor was the size of the stripping, roughly about 11-12mm. i think most people are using anywhere from an 8.9-9.5 punch. we will definitely use a punch in future surgies as the much larger graft was also much more difficult to work with!

-cjkurz

[cjkurz]

toval44-

great questions!

1. descemet's membrane always scrolls so the endothelium in on the OUTSIDE. this helps you know the right orientation. so if you have the graft is up against the posterior stroma and the edges are scrolling towards the iris then you know the graft is upside down. the edge are scrolling towards the stroma then you know the endothelium is facing the iris like it should!

i'll respond to your other questions in a different comment as my word count is limited!

cjkurz

[toval44]

How do you make sure that the graft is properly oriented against the host cornea? is the trypan blue help for this orientation? what is the size of the donor? no punch? why does the graft scrolled with the endothelium up

[cjkurz]

juanalvarezdetoledo-

thank you for your comment. i think you are right, we definitely need better instruments.

once descemet's is stripped from the posterior stroma on the donor, it scrolls up with the endothelium on the outside. we have not yet found a way to load the tissue so it enters the eye with the correct orientation. that would certainly make the procedure much easier!

[juanalvarezdetoledo]

Can you place de donor in the ICL injector in a way that when it is inserted the Descemet is face up and enothelium face down, so you only need to unfold it with little air bubbles? Is it worth it to use 25 G instruments to manipulate this tissue? I think we anterior surgeons must move to smaller instruments like Vitreorretinal surgeons have done.

[cjkurz]

valerybrs-

thanks for your comment. dsaek is by no means relinquished to the past. there is still so much room for improvement with dmek!

[valerybrs]

amazing!!!

is DSAEK in past?