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PURPOSE To assess the results of a single eye bank preparing a high volume of Descemet membrane endothelial keratoplasty (DMEK) tissues using multiple technicians to provide an overview of the experience and to identify possible risk factors for DMEK preparation failure. DESIGN Cross-sectional study. METHODS SETTING Lions VisionGift and Wilmer Eye Institute at Johns Hopkins Hospital. STUDY POPULATION All 563 corneal tissues processed by technicians at Lions VisionGift for DMEK between October 2011 and May 2014 inclusive. OBSERVATION PROCEDURES Tissues were divided into 2 groups: DMEK preparation success and DMEK preparation failure. MAIN OUTCOME MEASURES We compared donor characteristics, including past medical history. RESULTS The overall tissue preparation failure rate was 5.2%. Univariate analysis showed diabetes mellitus (P = .000028) and its duration (P = .023), hypertension (P = .021), and hyperlipidemia or obesity (P = .0004) were more common in the failure group. Multivariate analysis showed diabetes mellitus (P = .0001) and hyperlipidemia or obesity (P = .0142) were more common in the failure group. Elimination of tissues from donors either with diabetes or with hyperlipidemia or obesity reduced the failure rate from 5.2% to 2.2%. Trends toward lower failure rates occurring with increased technician experience also were found. CONCLUSIONS Our work showed that tissues from donors with diabetes mellitus (especially with longer disease duration) and hyperlipidemia or obesity were associated with higher failure rates in DMEK preparation. Elimination of tissues from donors either with diabetes mellitus or with hyperlipidemia or obesity reduced the failure rate. In addition, our data may provide useful initial guidelines and benchmark values for eye banks seeking to establish and maintain DMEK programs.

It is possible to prepare, evaluate, and ship DMEK grafts loaded inside a glass carrier and viewing chamber. The ability to evaluate tissues after processing allows for adherence to the Eye Bank Association of America Medical Standards, and for surgeons to receive the most accurate tissue information.

Purpose. To evaluate Fourier-domain optical coherence tomography (FD-OCT) as an adjunct to traditional slit lamp examination of donor corneas with suspected Anterior Stromal Opacities. Methods. Seven corneas suspected of having anterior stromal opacities by slit lamp examination were evaluated with FD-OCT. Each cornea was evaluated to confirm the presence of opacity and, if present, the depth of opacity was measured. Results. The opacity depth ranged from 82 μm to 624 μm. The initial slit lamp impressions of five of the seven corneas were confirmed by OCT. In two corneas, the OCT findings were different from the initial slit lamp impressions. Slit lamp examination of the first cornea gave the impression of anterior stromal scarring, but OCT showed that the opacity was limited to the epithelium. Slit lamp examination of the second cornea suggested opacity limited to the epithelium, but OCT identified significant sub-Bowman's scarring. In all cases, the Eye Bank Technicians reported that the location and depth of corneal opacity were more sharply defined by OCT than by slit lamp. Conclusion. The high resolution of OCT makes it easier to determine the location of corneal opacities compared to slit lamp examinations. This enhanced visualization can improve decisions regarding transplant suitability of donor corneas.

FLs are useful in preparing DMAEK tissue at the eye bank and may promote predictable and precise big bubbles and stromal rims. The fDMAEK preparation success improved with experience and laser adjustments. In fDMAEK, the ECL is higher than was previously reported in DMEK and DSEK, likely due to greater tissue manipulation, although not significantly higher than DSEK controls.

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.

Purpose To evaluate the DSAEK graft deturgescence in preservation medium after microkeratome cut using Fourier-domain optical coherence tomography (FD-OCT). Methods The central and peripheral thickness of DSAEK graft was measured by FD-OCT immediately after microkeratome cuts as well as 1 hour, 2 hours, 3hours, and 4 hours afterwards. All measurements were taken when the grafts were stored in 4°C preservation medium. The hourly change in central graft thickness and graft shape (peripheral – central graft thickness) was calculated and tracked over time. Results Five DSAEK grafts were measured. The average central graft thickness was 188.7 μm ± 44.4μm (range: 146μm ~ 255μm) immediately after microkeratome cuts. The average central graft thickness was 147.5 μm ± 33.0 μm (range: 116μm ~ 190μm) after 4 hours in preservation medium (p < 0.001). The average hourly change in central graft thickness was -30.5 μm (p = 0.0051), -8.6 μm (p = 0.055), -2.0 μm (p = 0.42) and 0.0 μm (p = 0.93) at 1 hour, 2 hours, 3hours, and 4 hours after microkeratome cuts. The average hourly change in graft shape was insignificant. Conclusion DSAEK grafts become thinner after microkeratome cut and stabilize at about 2 hours. Therefore, DSAEK graft thickness should be measured at 1.5 – 3 hours after microkeratome cut.

Purpose:To examine tissue loss rates, processing time, and primary graft failure (PGF) of "prestripped-only" Descemet membrane endothelial keratoplasty (DMEK) grafts at a single eye bank and how these parameters changed after the introduction of steps to preload tissue among experienced processors.Methods: Tissue loss and processing time during DMEK graft preparation as well as PGF were analyzed retrospectively at a single eye bank between 2012 and 2018. Outcomes were assessed in consecutive grafts before and after the introduction of preloading to the eye bank's standard operating procedure.Results: A total of 1326 grafts were analyzed, composed of the first 663 preloaded DMEK grafts and, for comparison, the 663 DMEK grafts processed immediately before starting the preloaded service. Mean processing time increased from 17.0 6 3.9 minutes to 26.0 6 5.4 minutes with the advent of preloading (P , 0.01). Initially, average processing time increased dramatically, with a maximum processing time of 51 minutes, before regressing to the average. No significant difference in the rate of tissue wastage was observed before versus after the implementation of preloaded DMEK (1.2% vs. 1.7%, P = 0.48). PGF occurred in 7 grafts before the preloaded service and 10 grafts after starting the service (1.6% vs. 2.3%, P = 0.47).Conclusions: Preloading does not affect tissue wastage for experienced technicians or the PGF rate but increases processing time. Eye banks that are considering adding preloading to their standard operating procedure may need to account for longer processing times in their daily operations.