Eyeworld

54 | EYEWORLD | SEPTEMBER 2023 C ORNEA COMPLICATED CASES About the physicians W. Barry Lee, MD Medical Director Georgia Eye Bank Atlanta, Georgia Elmer Tu, MD Professor of Clinical Ophthalmology University of Illinois College of Medicine Chicago, Illinois by Ellen Stodola Editorial Co-Director W. Barry Lee, MD, and Elmer Tu, MD, spoke with EyeWorld about the risk of infections with lamellar corneal grafts, how patients may present, and how to handle this complication. Any time a lamellar graft is done, whether it is an endothelial keratoplasty (EK) or anteri- or lamellar keratoplasty (ALK), an interface is created, Dr. Lee said. That interface has the po- tential to trap organisms and lead to a corneal infection. The most common interface infections occur from fungal organisms, particularly Can- dida species, Dr. Lee said. "Fortunately, lamellar graft infections are rare, but when they occur, they can be devastating," he said, noting that Fontana et al. 1 reported the rate of fungal infections after ALK is 0.052% and 0.022% after EK. Dr. Tu agreed that the most common infec- tions that occur with lamellar corneal grafts are caused by Candida species. The rate of infection from the most recent 2022 data is approximate- ly three infections per 10,000 endothelial grafts in the U.S. The true number is likely higher due to incomplete reporting, he said. He added that infections are generally rec- ognized at the 1-month follow-up appointment or later. "However, almost all infections are in- troduced at the time of surgery," he said. When an infection becomes apparent, it is affected by the virulence of the organism, the number of organisms, and their location. Aggressive, high colony count, or peripheral/anterior chamber location contamination could become appar- ent in the first few hours or days after surgery, whereas the opposite may not become apparent for months. Rarely, late infections have been reported more than a year later, Dr. Tu said. Interface infections can occur at any time after surgery, from a week after surgery to a year after, Dr. Lee said. Taking a fungal rim or media culture at the time of surgery can provide insight as to whether an organism is present on the donor tissue because infections are most commonly a result of transmission from the donor tissue. Patients typically present with decreased vi- sion and occasionally discomfort and photopho- bia. "Initially, the eye tends to be quiet, but as the infection progresses, the eye becomes more red and irritated," Dr. Lee said. "Slit lamp exam will often show a small white infiltrate in the interface of the cornea with anterior chamber cell and flare." The majority of infections are asymptomatic or minimally symptomatic at the time of recog- nition, Dr. Tu said. As it advances, decreased vi- sion, pain, and redness may occur. The infection usually presents with signs of inflammation, often subtle, as an isolated interface opacity but can present as an endophthalmitis, iritis, kerati- tis, or conjunctival inflammation. In order to try to reduce the risk of in- fection, Dr. Tu said efforts have been focused on two areas: reducing/limiting transmission and prophylaxis. "A number of eye bank and surgeon practices have been implemented to reduce contamination, including additional antiseptic applications at the time of recovery, reiterating aseptic techniques, and minimizing tissue warming," he said. "Exploration of adding antifungals to cold storage has not eliminated Handling lamellar graft infections Lamellar infection after DMEK with Candida species Source: W. Barry Lee, MD

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