Purpose: To evaluate the suitability of corneas from septic donors for transplantation by analyzing the discard rate in the eye bank and the clinical outcome of Descemet membrane endothelial... Show morePurpose: To evaluate the suitability of corneas from septic donors for transplantation by analyzing the discard rate in the eye bank and the clinical outcome of Descemet membrane endothelial keratoplasty (DMEK) using organ-cultured corneal grafts from septic versus nonseptic donors. Methods: This retrospective study included 1554 corneas of which 456 corneas (29%) were from septic and 1072 corneas (69%) from nonseptic donors [for 26 corneas (2%) sepsis status was unknown]. The clinical outcome at 6 months after DMEK was evaluated for 82 grafts (26 from septic and 56 from nonseptic donors). Outcome measures were endothelial cell density, central corneal thickness, and postoperative complications. Results: Primary discard rates were higher for corneas from septic than from nonseptic donors (32.9% vs. 24.5%, P = 0.001). The main discard reason was poor endothelial cell quality for both septic (13.8%) and nonseptic (11.8%) donor corneas. Eye bank contamination rates for septic and nonseptic donor corneas were 1.1% and 1.7%, respectively (P = 0.102). After DMEK, donor endothelial cell density at 6m postoperatively was comparable between grafts from septic and nonseptic donors (1410 +/- 422 cells/mm(2) vs. 1590 +/- 519 cells/mm(2), P = 0.140). No differences in 6m central corneal thickness and in the rebubbling rate were observed between the 2 groups (P = 0.780 and P = 0.396, respectively). None of the cases had graft rejection nor endophthalmitis in both groups. Conclusions: Provided strict adherence to donor screening and evaluation protocols, the use of organ-cultured corneas from septic donors for DMEK does not seem to increase the risk for recipients and allows for expansion of the donor pool for corneal tissue. Show less
Purpose:To report the 5-year graft survival and clinical outcomes after Descemet membrane endothelial keratoplasty (DMEK).Methods:A retrospective, interventional case series was performed at a... Show morePurpose:To report the 5-year graft survival and clinical outcomes after Descemet membrane endothelial keratoplasty (DMEK).Methods:A retrospective, interventional case series was performed at a tertiary referral center. Five hundred eyes of 393 patients that underwent DMEK for Fuchs endothelial corneal dystrophy, bullous keratopathy, failed previous corneal transplants other than DMEK, or other indications were evaluated for graft survival, best-corrected visual acuity (BCVA), endothelial cell density, postoperative complications, and retransplantation rate.Results:Kaplan-Meier analysis demonstrated an estimated survival probability of 0.90 [95% confidence interval, 0.87-0.94] for the entire cohort at 5 years after DMEK. At this time point, 82% of the eyes achieved a BCVA of >= 20/25 (0.8), 54% achieved >= 20/20 (1.0), and 16% achieved >= 20/17 (1.2). BCVA continued to improve from 6 to 36 months after DMEK surgery (P <= 0.005) and then remained stable up to 60 months postoperatively (P > 0.08). Preoperative donor endothelial cell density averaged 2530 (210) cells/mm(2) and decreased by 37% at 6 months, 40% at 1 year, and 55% at 5 years after DMEK surgery (P < 0.001 between all follow-up time points). During the study period, allograft rejection episodes developed in 2.8% of the eyes, primary graft failure occurred in 0.2%, and secondary graft failure in 2.8% of the eyes. Re-keratoplasty was required in 8.8% of the eyes.Conclusions:Five-year graft survival after DMEK is high, and visual acuity outcomes remain excellent and are accompanied by a low longer-term complication rate. Show less
Purpose:To report clinical outcomes of the first Quarter-Descemet membrane endothelial keratoplasty (Quarter-DMEK) case series performed for central Fuchs endothelial corneal dystrophy.Methods:This... Show morePurpose:To report clinical outcomes of the first Quarter-Descemet membrane endothelial keratoplasty (Quarter-DMEK) case series performed for central Fuchs endothelial corneal dystrophy.Methods:This is a prospective, interventional case series analyzing the clinical outcomes of 19 eyes of 19 patients with central Fuchs endothelial corneal dystrophy, that is, with guttae predominantly in the 6- to 7-mm optical zone, who underwent unilateral Quarter-DMEK at a tertiary referral center. Main outcome measures were best-corrected visual acuity (BCVA), endothelial cell density (ECD), and postoperative complications. Included eyes had up to 2 years of postoperative follow-up.Results:At 6 months postoperatively, all eyes reached a BCVA of >= 20/40 (>= 0.5): 18 of 19 eyes (95%) with >= 20/25 (>= 0.8) and 9 of 19 eyes (42%) with >= 20/20 (>= 1.0). Thereafter, BCVA remained stable up to 2 years postoperatively. The mean donor ECD decreased from 2842 139 cells/mm(2) (n = 19) before implantation to 913 +/- 434 cells/mm(2) (-68%) at 6 months (n = 19), 869 +/- 313 cells/mm(2) (-70%) at 12 months (n = 18), and 758 +/- 225 cells/mm(2) (-74%) at 24 months (n = 13) after Quarter-DMEK. Visually significant graft detachment requiring rebubbling occurred in 8 of 19 eyes (42%).Conclusions:Quarter-DMEK surgery yields visual outcomes similar to those of conventional DMEK and may potentially quadruple the availability of endothelial grafts. Further modifications of the graft preparation and the surgical technique may improve clinical outcomes in terms of lower ECD decrease and fewer graft detachments. Show less
After penetrating keratoplasty had been the preferred method for the treatment of corneal disorders for almost a century, the introduction of lamellar keratoplasty techniques has changed the... Show moreAfter penetrating keratoplasty had been the preferred method for the treatment of corneal disorders for almost a century, the introduction of lamellar keratoplasty techniques has changed the field of corneal transplantation substantially over the last two decades. These lamellar keratoplasty techniques provide several advantages over penetrating keratoplasty: anterior lamellar keratoplasty may potentially improve graft survival by preserving the healthy recipient endothelium in the management of corneal stromal diseases, and endothelial keratoplasty has improved the predictability and speed of visual rehabilitation for treating endothelial disorders, mainly by leaving the anterior corneal surface intact. The latest innovation in the field of endothelial keratoplasty is Descemet membrane endothelial keratoplasty (DMEK), in which only the Descemet membrane and endothelium are replaced by donor tissue. The trend towards more selective and minimally invasive transplantation techniques has also led to the development of new treatment options for patients with (advanced) keratoconus, including the mid-stromal implantation of an isolated donor Bowman layer, referred to as Bowman layer-transplantation. This thesis focusses on the feasibility and clinical outcomes of these two modern lamellar keratoplasty techniques, i.e. DMEK for endothelial disorders, and Bowman layer-transplantation for advanced keratoconus. Show less
