EyeWorld Asia-Pacific March 2018 Issue

16 EWAP FEATURE September 2017 David Rootman, MD, and have added some modifica- tions to his original technique. Since I was getting some peripheral tissue tears (both radial and circumferential), we developed a technique of scleral spur disinser- tion prior to endothelium dissec- tion. This scleral spurectomy is performed by doing a manual scle- ral spur disinsertion 360 degrees using a toothed forceps. Then, I continue the dissection using a Sloane LASEK microhoe, dissecting Schwalbe’s line in 360 degrees as described by Dr. Rootman. 2 I continue the dissection of the endothelial layer using a non- toothed forceps. Once I’ve reached 60% of the dissection, I create a stromal corneal window on the remaining corneal stroma using a 2-mm dermatological punch, which allows me to mark the tissue with the letter “F.” This will help me determine tissue orientation during the insertion per the technique described by Mark A. Terry, MD. Once the tissue has been marked, I complete the dissection with a non-toothed forceps using a rhexis motion. This technique requires a Sloane LASEK microhoe and a standard toothed and non-toothed forceps, a dermatological punch, a marking pen, standard spatula and a stand- ard Barron donor trephine. Since starting the scleral spurec- tomy, this technique has allowed me to save every single tissue for at least 70 DMEK cases. This is espe- cially important in the country I live in where corneal donor tissue is rare, and I cannot allow the loss of any tissue during preparation. If peripheral radial or circumfer- ential tears occur, this technique allows for decentration of the final donor during trephination, avoid- ing the area that might have been damaged during tissue preparation. Mark A. Terry, MD, director of corneal services, Devers Eye Institute, and professor of clinical ophthalmology, Oregon Health Sciences University, Portland, Oregon 62-year-old male with BSCVA of 20/20 as early as 2 weeks after DMEK and phaco plus IOL for Fuchs’ endothelial dystrophy Source: Mohit Parekh, PhD I do not prepare the DMEK tis- sue myself anymore. I have taught the technicians in our eye bank, Lions VisionGift (LVG), Portland, Oregon, to do this. They prepare dozens of tissues every week so they are better at it than most surgeons, taking the risk of tissue preparation out of the operating suite and into the eye bank. This is for the benefit of the surgeon. They use a technique of Descemet’s stripping that leaves a hinge at the edge of the tissue and place an S-stamp on Descemet’s membrane to help surgeon orientation. They now also offer “patient-ready” preloaded tissue. I recommend that surgeons not strip their own tissue and instead let the eye bank do it for them. If their eye bank does not “pre-strip” DMEK tissue, then their eye bank can send their local tissue to LVG or another processing eye bank to do the preparation for them. Why take the risk when the eye bank can do it all for you? In addition to pre-stripped, pre-marked, pre-stained, and pre-trephinated tissue, I also use preloaded patient-ready DMEK tissue. We have been using this since March 2017 and now have about 100 cases of DMEK with preloaded tissue. The results are comparable to when we were using pre-stripped tissue but loading it ourselves. However, the advantages of using patient-ready preloaded tissue are enormous. Because the surgery center does not have to buy a trephine, trypan blue, or Straiko injector, there are significant cost savings. There is increased safety because the surgeon does not have to worry about tissue damage at any of the surgery stages. There are additional savings because with the elimination of tissue prepara- tion and loading of the tissue, there is a much shorter operating room time. The result of using preloaded tissue is a safer, more efficient, and less costly DMEK operation. The clinical results (e.g., graft survival and endothelial cell loss) are no different than when the tissue was prepared by the surgeon. I predict that the use of patient- ready preloaded DMEK tissue will allow more widespread adoption of DMEK surgery in the U.S. and around the world. EWAP References 1. Parekh M, et al. Standardizing Descemet membrane endothelial keratoplasty graft preparation method in the eye bank experi- ence of 527 Descemet membrane endothelial keratoplasty tissues. Cornea . 2017;36:1458–1466. 2. Perez M, et al. Fighting tears. The Ophthalmologist . September 2016. theophthalmologist.com/is- sues/0816/fighting-tears/ Editors’ note: The physicians have no financial interests related to their comments. Contact information Borovik: aborovik@gmail.com Busin: mohit.parekh@fbov.it Parekh: mohit.parekh@fbov.it Perez: mauricioperezvelasquez@gmail.com Tan: reg_tan6@yahoo.com Terry: mterry@deverseye.org Best practices - from page 15 March 2018