Comparative Evaluation of Graft Thickness and Endothelial Cell Loss in Preloaded DSAEK Grafts During Extended Hypothermic Storage.

PURPOSE: To compare the graft thickness and cell viability of preloaded Descemet stripping automated endothelial keratoplasty (DSAEK) grafts in the corneal storage solutions XTRA4 and Optisol-GS for up to 6 days. METHODS: Cornea pairs were prepared as preloaded DSAEK grafts, with 1 stored in Optisol-GS and the mate in XTRA4. Two carriers were tested (Weiss Glass Cannula and EndoGlide Ultrathin, N = 5 pairs each). OCT measurements were taken postcut, and 1 hour, 1 day, and 6 days postload at the same graft location each time. Endothelial cell loss (ECL) was assessed by calcein-AM staining and FIJI segmentation. RESULTS: In the Weiss Glass Cannula group, grafts stored in XTRA4 (cut to 105.0 ± 27.2 μm) swelled 28% from their original thickness after preloading but remained stable for 6 days, whereas Optisol-GS stored grafts (cut to 100.8 ± 10.9 μm) swelled 32% after preloading and increased by 70% over 6 days. In the EndoGlide group, grafts stored in XTRA4 (cut to 118.4 ± 16.4 μm) swelled 18% after preloading and decreased in thickness over 6 days, whereas Optisol-GS grafts (cut to 95.8 ± 6.9 μm) swelled 14% initially and thickened 48% over 6 days. ECL was 21% versus 23% (XTRA4 vs. Optisol-GS) in Weiss Glass Cannula grafts and 11% versus 14% in EndoGlide grafts. The difference in ECL between XTRA4 grafts stored in each carrier was significant (P < 0.05). CONCLUSIONS: XTRA4 preserves graft thickness during extended hypothermic storage and minimizes swelling in preloaded DSAEK grafts. These properties enhance logistics and the feasibility of long-distance shipping, including intercontinental transport.