EyeWorld Asia-Pacific December 2013 Issue
29 EWAP rEfrActivE December 2013 Corneal transplantation: Impact of the widening pool of prior refractive surgery donors by Maxine Lipner EyeWorld Senior Contributing Writer continued on page 30 The question of how and when to use corneas from donors who had prior LASIK, PRK, or RK is grow- ing in significance P atients who have undergone refractive surgery are here to stay and are potentially part of the corneal donor pool, according to Mark A. Terry, MD , director of corneal services, Devers Eye Institute, and professor of clinical ophthalmology, Oregon Health & Science University, Portland, Ore., USA. “There have been millions of LASIK patients in the United States, and a good portion of those patients will become donors in the future,” Dr. Terry said. Already corneas from those who have undergone LASIK, PRK, and even RK are becoming a part of the pool for partial-thickness transplants, but are not eligible for traditional transplants. “Right now the Eye Bank Association of America does not allow a person who has had LASIK, PRK, or RK or who has any corneal scars to be a donor for a full-thickness corneal transplant,” Dr. Terry said. “The reason is because if you transplant an eye that’s got a scar, you’re putting a defective cornea into the recipient, and if you try and do a full-thickness penetrating keratoplasty from a donor who has had LASIK, the surface can fall apart.” DMEK with 20/20 results from a donor with LASIK Source: Mark A. Terry, MD An in-place DSAEK in a pseudophakic patient Source: John D. Sutphin, MD refractive impact To this point, however, the impact has been limited, observed David B. Glasser, MD , assistant professor of ophthalmology, Johns Hopkins University School of Medicine; in practice, Patapsco Eye MDs, Columbia, Md., USA; and chair elect, Eye Bank Association of America. “In 2012 there were approximately 115,000 tissues recovered and about 30,000 or so of the donor tissues couldn’t be released for one reason or another,” Dr. Glasser said. “About 12,000 were disqualified due to a problem with the tissue; only 298 (0.3%) were disqualified due to prior refractive surgery.” Kenneth S. Himmel, MD , cornea specialist, Eye Associates of New Mexico, Albuquerque, NM, USA, and medical director, New Mexico Lions Eye Bank, explained that there is currently no shortage. “Of the total tissues that were released for transplantation, 4,900 of these were never used,” he said. Still, in the future, it might be a bigger issue, Dr. Himmel noted. “As prior refractive surgery patients reach an age where they may be more likely to donate tissue, this may have a potentially bigger impact on the supply,” he said. “Also, you can’t always tell that the patient had prior refractive surgery, so it’s quite possible that some of the tissue that was released may have been from patients who had refractive surgery and it wasn’t able to be detected.” Dr. Glasser agreed that this is a possibility. “There are a couple of anecdotal reports in the literature of tissue that, to the surprise of the surgeon, delaminated into an anterior and posterior section because the donor had prior LASIK that was missed,” he said. However, he thinks that the eye banks catch the vast majority of these. New life for LASiK tissue John E. Sutphin, MD , Luther and Ardis Fry professor and chairman, Department of Ophthalmology, University of Kansas Medical Center, Prairie Village, Kan., USA, noted that the move toward partial-thickness transplantation procedures has given new life to refractive tissue. “Now with the change in procedures moving toward lamellar-type surgery, donors who’ve had LASIK or PRK can still be used for deep transplants or endothelial transplants like DMEK (Descemet’s membrane endothelial
Made with FlippingBook
RkJQdWJsaXNoZXIy Njk2NTg0