DescePrep Significantly Increases Descemet Membrane Endothelial Keratoplasty Processing Efficiency and Success Rate in Diabetic Human Donor Corneas in Comparison With Manual Dissection.

PURPOSE: The purpose of this study was to compare the safety, efficacy, and efficiency of a Descemet membrane endothelial keratoplasty (DMEK) graft processing device, DescePrep, with a manual dissection technique through the measurement of tissue yield, processing time, and graft viability in nondiabetic and diabetic donor corneas. METHODS: Nondiabetic (n = 20) and diabetic (n = 20) donor corneas were processed using DescePrep, which standardizes the liquid bubble technique. Nondiabetic (n = 20) and diabetic (n = 24) donor corneas were also processed through manual dissection. Corneas were stained, processed, and then evaluated for processing success rate and time. Randomly selected corneas (n = 5, each) were evaluated for cell viability using live/dead staining. RESULTS: One hundred percent of nondiabetic and 95% of diabetic corneas were processed successfully with DescePrep in an average of 3.37 minutes. Ninety percent of nondiabetic and 50% of diabetic corneas were processed successfully with manual dissection in an average of 9.87 minutes. DescePrep had a significantly lower processing time ( P < 0.0001) and significantly higher success rate in comparison with manual dissection. DescePrep grafts had an average cell viability of 91.1% ± 3.3% in nondiabetic and 91.5% ± 2.4% in diabetic corneas. Grafts prepared with manual dissection had an average cell viability of 89.5% ± 5.8% in nondiabetic and 88.1% ± 4.3% in diabetic corneas. CONCLUSIONS: DescePrep provides a more effective and efficient method of cornea preparation in comparison with the current standard, particularly in diabetic corneas, while providing comparable cell viability. Thus, DescePrep offers standardized DMEK processing that produces high-quality grafts at high yields, with the potential to expand access and improve the quality of DMEK graft preparation in a larger pool of donors.

Eliminating Regurgitation Reduces Fibrotic Remodeling of Functional Mitral Regurgitation Conditioned Valves.

Functional mitral regurgitation (FMR) is an insidious and poorly understood condition affecting patients with myocardial disease. While current treatments reduce regurgitation, their ability to reverse mitral valve pathology is unclear. We utilized a pseudo-physiological flow loop to study how repair impacted valve composition. Porcine mitral valves were cultured in control geometry (native papillary muscle position and annular area) or high-tension FMR geometry (5 mm apical and 5 mm lateral displacement of papillary muscles, 65% increased annular area) for 2 weeks. To mimic repair, a reversal condition was created by returning one-week FMR conditioned valves to a non-regurgitant geometry and culturing for 1 week. Valve composition and material properties were analyzed. After two-week culture, FMR conditioned tissues were stiffer and stronger than control and underwent extensive fibrotic remodeling, with increased prolyl-4-hydroxylase, lysyl oxidase, matrix metalloproteinase-1, and decorin. The reversal condition displayed a heterogeneous, leaflet- and orientation-dependent response. Reversal-conditioned anterior leaflets and circumferential tissue sections continued to have significant fibrotic remodeling compared to control, whereas reversal-conditioned posterior leaflets, chordae tendineae, and radial tissue sections had significantly decreased remodeling compared to FMR-conditioned tissues. These findings suggest current repairs only partially reverse pathology, underscoring the need for innovation in the treatment of FMR.