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Dr. Choremis on DMEK

Why there is no alternative to using the GEUDER cartridge for DMEK


Johanna Choremis, MD, FRCSC Assistant Professor of Ophthalmology, McGill University Professeure adjoint de clinique, Université de Montreal

Date: Oct 4, 2018


GEUDER: Dr. Choremis, you started with DMEK in 2015 and after three years of experience you perform almost 100 DMEKs per year. What have you learned in the past three years and what is your personal rationale for the rising popularity of this surgical technique?

Dr. Choremis: First of all, this surgery is an exact anatomic replacement. It barely changes the refractive error, and it also has less rejections. In addition, I find surgeons are really catching on to the technique and I don’t find it any harder than DSAEK anymore. In the beginning it was stressful and I didn’t know how to do it but now I feel like it’s just as quick as a DSAEK. So I think with experience it becomes much easier. Occasionally, you can have trouble unfolding the graft or trouble with fibrin but overall, for the standard, case it’s quite smooth.


GEUDER: And do you teach also young colleagues in performing DMEK?

Dr. Choremis: Yes. We have fellows yearly, often 2 a year. Most fellowships do teach DMEK these days.


GEUDER: And you perform the DMEKs always, or most of the time with a DMEK cartridge from GEUDER?

Dr. Choremis: All the time! There was a time when it was on backorder and I had to try the Jones [tube] and it was terrible. I also tried the lens cartridges [IOL shooters] which was also a nightmare in my opinion.


GEUDER: What was most annoying about the Jones tube and IOL cartridge?

Dr. Choremis: It’s big and it’s bulky. You have to try it before you put it in to make sure that it fits through your incision. You cannot count on the Jones being the same size every time. Geuder is always exact, the size is always the same. With your 2.4 mm keratome incision, it fits perfectly every time. This perfect fit keeps the chamber stable and you don’t have to worry about fluid coming out of the anterior chamber. It’s not as big, it’s not as bulky. I’ve also tried the IOL injector and that was very tough. With the IOL cartridge , you have to take IV tubing and connect it to the syringe. It becomes a makeshift gadget where the IV tubing sometimes detaches. Your graft gets squished, moves in the improper direction… it was a disaster. I couldn’t use it. High risk for damaging the graft.

GEUDER: I see.

Dr. Choremis: I find it’s a big difference. And actually one of the other questions was “how did I get starting to use it?” Well my colleague Julia Talajic did a fellowship with Mark Terry and they were using the Jones [tube]. But they had a wetlab with GEUDER and she thought it was amazing. So when she came back to Canada she tried to see where we could get it. She started using and that’s how I got to use it. I didn’t even think to use other tubes because we had the Geuder from the beginning. Thanks to her we are all using it at our hospital but probably if she hadn’t had that wetlab on her fellowship, she wouldn’t have had the opportunity to try it.

At the time when it was on backorder we wanted the Geuder back, and we would joke with our nurses, making signs that said BBTG: “bring back the Geuder”. We had some great laughs. Having tried other cartridges I don’t see why anyone would want to not use a Geuder.


GEUDER: I have another question. You told us about the pre-stripped and pre-loaded tissue. You sometimes use pre-stripped tissue, is that right?

Dr. Choremis: Yes, we always use pre-stripped tissue from our local eye bank and we also buy some from the US.


GEUDER: Could you imagine using pre-loaded tissue where the Descemet membrane is already prepared completely and comes in a cartridge?

Dr. Choremis: Yes, for sure.


Dr. Choremis: It would be coming pre-loaded in the Geuder cartridge?

GEUDER: Yes. The actual product goes to the cornea bank, they unwrap it and load it with a pre-stripped cornea, with a Descemet lamella, which is already completely prepared and put into the cartridge. The cartridge itself is a bit longer because it requires a bit more buffer or cell culture medium and then it’s put into a cell culture flask and this flask is then sent out to you. And you can take it out of the box and you can wash it. Once you have only buffer in the cartridge, you may restain the lamella and then you can flush it directly out of this cartridge into the patient’s eye.


Dr. Choremis: You would restain it in the cartridge?

GEUDER: Yes. You have two permeable plugs. A front plug and a rear plug and the front plug can be connected to a syringe together with the tubing. Then you can go slowly replace the cell culture media with BSS and you can also put some dyes in it and wash it a second time. And everything can be done in the cartridge.

Dr. Choremis: We would love that. I mean we don’t have the preloaded system but we would love that obviously and it would make the surgery even faster. We wouldn’t have to sit there and stain the “S” and prepare. Restain it, reload it. Loading especially with the fellows sometimes is not so easy. It doesn’t always come into the little tube… it’s a little bit of experience. That would definitely make it easier.


GEUDER: Thank you very much for your time!

(GEUDER: Dr. Stefanie Degenhartt, Tim Pieplau)