Outcomes of fresh versus short-term preserved stromal tissues obtained from DMEK in DALK surgery

To evaluate the outcomes of deep anterior lamellar keratoplasty (DALK) using stromal tissues obtained during Descemet membrane endothelial keratoplasty (DMEK) and to compare the effectiveness of fresh versus three-day-stored grafts. This two-center retrospective study included 42 eyes of 42 patients who underwent DALK using DMEK-derived stromal tissues. Patients were divided into two groups: Group 1 (n = 23), in which fresh stromal tissue was used on the day of surgery, and Group 2 (n = 19), in which stromal tissue stored under cold-chain conditions-defined as transportation with the tissue temperature consistently maintained at approximately 4 °C-for three days was used. Preoperative and postoperative evaluations included best-corrected visual acuity (BCVA), intraocular pressure, slit-lamp and fundus examination, and corneal tomography (Pentacam HR; Oculus, Germany). Demographic data, intraoperative characteristics, postoperative graft transparency, and complications were compared between groups. The groups were similar regarding demographic features, surgical indications, anesthesia type, and suture technique (all p > 0.05). Graft transparency did not differ significantly between the groups on postoperative day 1 or at the last visit (p = 0.597, p = 0.890). Double anterior chamber formation occurred in 3 eyes (15.8%) in Group 1 and 6 eyes (26.1%) in Group 2 (p = 0.418). Other complications, including glaucoma, cataract, epithelial defects, and keratitis, occurred at similar rates (all p > 0.05). BCVA, keratometric, pachymetric, and densitometric parameters significantly improved postoperatively in both groups, with no intergroup difference (all p > 0.05). Stromal tissue obtained during DMEK is a safe and effective graft source for DALK, whether used fresh or after short-term storage. This technique optimizes donor cornea utilization and may help alleviate the global donor shortage.