Retention of the Pre-Descemet's Layer Reduces Endothelial Graft Scrolling: Digital Morphometric Analysis of Precut Endothelial Grafts.

Purpose: To evaluate the biomechanical impact of the Pre-Descemet's Layer (PDL) on central graft width (CGW) and Scrolling Score (SS) using a standardized digital morphometric approach in pre-Descemet endothelial keratoplasty (PDEK) and Descemet membrane endothelial keratoplasty (DMEK) grafts. Methods: This experimental study analyzed 47 donor corneoscleral buttons. Grafts were prepared via pneumatic dissection into PDEK or DMEK. CGW and SS were quantified using FIJI-ImageJ software from standardized video frames. Statistical analysis included Student's t-tests, Pearson's correlation, and Chi-Square tests. Endothelial viability and global integrity were assessed in representative PDEK grafts using confocal microscopy with triple vital staining (Hoechst 33342, Ethidium-homodimer, and Calcein-AM). Results: Forty-one grafts were successfully prepared (24 PDEK; 17 DMEK). The failure rate was significantly higher in diabetic donors (50% vs. 7.3% in non-diabetics, p < 0.001). PDEK grafts exhibited a significantly higher mean CGW (2.35 ± 0.36 mm) compared to DMEK (1.95 ± 0.41 mm; p < 0.05). A clear inverse relationship was established between CGW and SS; SS-2 was predominant in PDEK (50%), while SS-3 prevailed in DMEK (70.5%). Donor age showed a weak correlation with CGW in DMEK (R2 = 0.283) and no correlation in PDEK (R2 = 0.0004). Trypan blue staining did not significantly alter CGW or SS in either group (p > 0.05). Confocal microscopy confirmed high endothelial viability (2407 cells/mm2) with minimal iatrogenic damage in tissue folds. Conclusions: Retention of the PDL significantly reduces endothelial graft scrolling and increases CGW values in PDEK compared with DMEK. Although donor age demonstrated a weak association with CGW in DMEK grafts, no such relationship was observed in PDEK. Digital morphometric analysis represents a reproducible approach for preoperative characterization of graft behavior in eye banks.