Single-Pass Dissection of Ultrathin Organ-Cultured Endothelial Lamellae Using an Innovative Microkeratome System.

Abstract

To determine the feasibility, dissection accuracy, and endothelial viability of ultrathin endothelial lamellae harvested from organ-cultured corneas using a single-pass with an innovative motor-driven linear microkeratome system. Forty-eight (n = 48) paired organ-cultured human corneas were randomly assigned to dissection (study eyes, n = 24) with fellow eyes serving as the control (fellow eyes, n = 24). After organ culture and deswelling in a medium containing 6% dextran, endothelial lamellae with a target thickness ≤100 μm were dissected using a motor-driven linear microkeratome system (SLc, Gebauer, Neuhausen, Germany) equipped with 400-μm (n = 4), 450-μm (n = 10), 500-μm (n = 5), or 550-μm (n = 5) heads. Central corneal thickness (CCT) and posterior and anterior lamellar thicknesses were measured using ultrasound pachymetry (Pachette 3; DGH Technology Inc, PA) and anterior segment optical coherence tomography (Casia SS-1000; Tomey, Nagoya, Japan). Endothelial viability [endothelial cell density (ECD)] was measured using trypan vital staining. CCT measured 595 ± 66 μm (n = 48) on arrival, 846 ± 131 μm (n = 48) after organ culture, and 565 ± 58 μm (n = 48) after deturgescence. CCT did not differ between study and control eyes. Posterior lamellar thickness measured 88 ± 18 μm (n = 24) immediately after dissection, 126 ± 30 μm (n = 24) 1 hour after dissection, and 131 ± 41 μm (n = 24) 2.3 ± 0.6 days after dissection. ECD measured 2637 ± 264 cells per square millimeter (n = 48) on arrival, 2524 ± 232 cells per square millimeter (n = 48) after organ culture, 2493 ± 253 cells per square millimeter (n = 48) after dissection, and 2311 ± 218 cells per square millimeter (n = 48) 2.3 ± 0.6 days after dissection. ECD did not differ between study and control eyes at all time points. Single-pass motor-driven linear microkeratome dissection provides an accurate and safe alternative for harvesting ultrathin endothelial lamellae from organ-cultured donor corneas.