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EW CORNEA 76 September 2016 "The relative hypoxia of the interface environment after EK may promote fungal virulence and re- duced access to the immune system, thereby increasing the risk for fungal keratitis," Dr. Tsui said. Ophthalmologists also must consider that corneal storage media in the U.S. is supplemented with antibacterial medication but not antifungal medication, Dr. Amescua said. The 2013 EBAA report said that despite a non-significant increas- ing rise in fungal keratitis after EK, there is not yet enough evidence to support antifungal supplementation of donor storage media. 1 Candida species are the most common cause of fungal infections after EK, including C. albicans, C. parapsilosis, and C. glabrata, Dr. Amescua said. Treating fungal keratitis after EK Multiple treatment approaches are used for fungal keratitis after EK, including topical, intravitreal, intra- cameral, and possibly even systemic antifungal agents upon diagnosis, Dr. Tsui said. Graft removal is also a possibility if clinical signs of infec- tion are present. "This would allow for cultures to be obtained and improve access of antifungal com- pounds to the host cornea," he said. Although at least one study has shown successful treatment with intracameral injection, 3 this approach has only been helpful in a small number of cases, Dr. Amescua said. Usually, a surgical intervention is necessary because antifungal med- ications have poor penetration of the deep corneal stroma, where the infection is located. "If the fungal keratitis is pro- gressing and there is evidence of intracameral extension, removal of all hardware (including intraocular lenses) and a full pars plana vitrecto- my may be necessary," Dr. Amescua said. Role of donor rim cultures The role of obtaining routine donor rim cultures to help track fungal ker- atitis after EK is still controversial. Although rim cultures have histor- ically had a low predictive value of infection, emerging literature and experience show that positive fungal cultures from donor rims of corneas used for EKs may indicate an in- creased risk of postop infection, Dr. Tsui said. In the study from Dr. Tsui and colleagues, among 99 DSAEK procedures performed at the same institution from 2012 to 2014, they found that 7.1% of donor rim cul- tures were positive for fungi. 2 "This report of correlated rim cultures and clinical infection suggests a need for re-evaluation of the utility of obtain- ing routine corneoscleral donor rim fungal culture," the authors wrote. Dr. Amescua sees a positive role for obtaining donor rim cultures. "Our group routinely sends cor- neal donor rims for surveillance cultures," he said. However, the cost-benefit analysis is debatable, as most of the rims sent for cultures are kept in culture for a few days and then discarded, which he said does not give time for the fungal organ- ism to provide a positive culture because of the slow growing nature of the organisms. "A review of the literature by Palioura et al. 4 showed that of 21 cases of fungal keratitis post-endothe- lial keratoplasty reported, donor rim cultures were done in 18 of the 21 reported cases, cultures were positive in eight of them (44%), negative in eight of them (44%), and not report- ed in two (11%) of the 18 cases," he said. EW References 1. Aldave AJ, et al. Report of the Eye Bank Association of America medical advisory board subcommittee on fungal infection after corneal transplantation. Cornea. 2013;32:149–154. 2. Tsui E, et al. Candida interface infections af- ter Descemet stripping automated endothelial keratoplasty. Cornea. 2016;35:456–464. 3. Tu EY, et al. Intrastromal antifungal injection with secondary lamellar interface infusion for late-onset infectious keratitis after DSAEK. Cornea. 2014;33:990–993. 4. Palioura S, et al. Fungal endophthalmi- tis after Descemet stripping automated endothelial keratoplasty due to endogenously infected grafts from the same donor. American Academy of Ophthalmology/Ocular Microbiol- ogy and Immunology Group meeting, Abstract 19, 2015, Las Vegas. Editors' note: The physicians have no financial interests related to their comments. Contact information Amescua: GAmescua@med.miami.edu Tsui: Edmund.Tsui@nyumc.org Uncommon continued from page 74 THE NEW STANDARD IN GLAUCOMA IMPLANT PATCH GRAFTS EASY-PEEL PACKAGING Patented easy-peel packaging allows for quick introduction of sterile tissues to the surgical field, saving valuable OR time. 99.9% CLARITY Unlike traditional patches, Halo tissue grafts are clear and will remain clear, resulting in simplified post-op assessment and improved patient cosmesis. 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