{
  "abstract": "Purpose Since the introduction of the Descemet membrane endothelial keratoplasty (DMEK) technique, this procedure has become the gold standard for treatment of endothelial indications. In 2022, 6274 posterior lamellar keratoplasties were performed in Germany, 98.7% of which were DMEK surgeries. 1 Accordingly, the German Society for Tissue Transplantation (DGFG) provides 75% of their corneas for DMEK. Initially, the lamellae were prepared by surgeons in the operating theatre (OT) right before transplantation. However, since 2015 pre-cut grafts (LaMEK) that are prepared in the tissue bank are available from the DGFG network. This can save time in OT and guarantees a safe, high-quality transplant. However, these preparatory steps include manipulation, so the question arises whether the tissue is of the same quality as transplants prepared in the OT.Methods Since its introduction, the DGFG has provided 3720 LaMEK. Each transplant is evaluated for quality, with endothelial cell density (ECD) being determined before preparation and before delivery 2 to 3 days later. With this, a possible preparation-related decrease of ECD can be detected.Results A retrospective analysis of lamella preparations between January 2022 and August 2024 showed that the preparation is successfully completed by the experienced technician in 95%. The ECD remains stable after lamella preparation, with a cell loss of less than 1% on average (mean ECD 2659 cells/mm2 before preparation, 2655 cells/mm2 on delivery, n=1355). In very few cases (13 out of 1355 = 0,96%), we received negative feedback on the quality of the pre-cut LaMEK. In contrast, although the overall rate of complaints is very low (170 out of 13.400), 70% (119) of them concern unsuccessful preparation of the lamellae in the OT.Conclusions The results show that the preparation of the lamellae by specialized personnel in the tissue bank yields in high-quality transplants. The great success rate in pre-preparation prevents the loss of valuable donor tissue. Under circumstances, in the tissue bank the preparation is also achieved with more difficult initial conditions (after cataract surgery or diabetes). The number of lamellar grafts provided successfully from the DGFG shows the effectiveness of the method. This contradicts the results of Heinzelmann et al. who determined a high graft failure rate with precut tissue in 2017. 2 Since then, different other groups provided evidence that the clinical results are also equivalent when precut lamellae are used.3 4 In summary, it can be stated that the use of pre-prepared lamellae from the tissue bank offers surgeons a safe and time-saving way of providing patients with high-quality transplants, even in smaller centers.References German Keratoplasty Registry, 2022.Heinzelmann, et al. Graefes Arch Clin Exp Ophthalmol. 2017;255(1):127–33.Rickmann, et al. Int Ophthalmol. 2022;42(2):401–409.Koechel, et al. Graefes Arch Clin Exp Ophthalmol. 2021;259(1):113–119.",
  "authors": [
    {
      "affiliations": [
        "German Society for Tissue Transplantation (DGFG – Deutsche Gesellschaft für Gewebetransplantation), Hannover, Germany"
      ],
      "name": "Nicola Hofmann"
    }
  ],
  "title": "5.6. 10 years’ experience with the pre-preparation of cornea lamellae in the tissue bank confirms the concept",
  "uid": "4759e9a4-38c7-5274-a499-a5ec57604c96"
}