This is the first report of the clinical use of prestained, preloaded tissue for DMEK. The characteristics and handling of the tissue were not different from those of surgeon-loaded tissue. Because punching, staining, and loading the graft intraoperatively is not necessary, the surgery time and risk of damaging donor tissue are reduced when using preloaded tissue.

A cloverleaf or parallel retention suture in conjunction with Descemet stripping automated endothelial keratoplasty seems to reduce the risk of detachment in high-risk patients, while maintaining adequate cell density and graft clarity at 1 year.

Purpose: To quantify endothelial cell loss (ECL) caused by orientation stamps on prestripped and preloaded Descemet membrane endothelial keratoplasty (DMEK) grafts, and to examine a method for reducing ECL using a smaller stamp. Methods: Ten prestripped and 10 preloaded DMEK grafts were prepared with S-stamps. Ten additional preloaded DMEK grafts were prepared with both an S-stamp and a smaller F-stamp in different paracentral areas of the graft. The footprint of each stamp was measured using ink on cardstock. DMEK grafts were stored in viewing chambers filled with 20 mL of Optisol-GS for 3 days at 4°C. ECL was quantified using Calcein-AM staining and FIJI Weka Segmentation. Results: S-stamps on prestripped DMEK grafts contributed an average ECL of 1.1% ± 0.5% (range: 0.6%–2.2%) toward total graft damage, whereas S-stamps on preloaded DMEK grafts contributed approximately twice that amount (average ECL: 2.0% ± 0.7%, range: 1.3%–3.1%, P = 0.004). Overall ECL for prestripped grafts (average: 7.1% ± 3.3%, range: 3.3%–13.7%) and preloaded grafts (average: 11.3% ± 4.2%, range: 6.9%–19.4%) was similar to previous reports. The footprint of the S-stamp was approximately 45% larger than that of the F-stamp. In 10 preloaded grafts marked with both stamps, the S-stamp caused an average ECL of 1.9% ± 0.6% (range: 1.2%–3.2%), whereas the smaller F-stamp caused an average ECL of 1.0% ± 0.2% (range: 0.8%–1.4%, P = 0.0002). Conclusions: Loss of endothelial cells associated with graft-stamping was greater in preloaded tissue than in prestripped tissue and was less with a smaller F-stamp than with a larger S-stamp. Using a smaller stamp could help minimize ECL in prestripped and preloaded DMEK grafts.

The histopathology of the endothelial disc from the patient with TIOs demonstrated variably irregular lamellae that extended from the anterior donor corneal stromal surface. These extending lamellae were absent on the anterior stromal surface of the control corneal disc, suggesting that they are one possible cause of TIOs and the subsequent suboptimal best-corrected visual acuity and quality of vision experienced by a subset of DSAEK-operated patients.

No abstract