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Claus Cursiefen - One of the best experts on this subject based on the ideXlab platform.

  • fuchs endothelial Corneal dystrophy clinical genetic pathophysiologic and therapeutic aspects
    Annual review of vision science, 2019
    Co-Authors: Mario Matthaei, Agathe Hribek, Thomas Clahsen, B Bachmann, Claus Cursiefen
    Abstract:

    Fuchs endothelial Corneal dystrophy (FECD) is a bilateral Corneal endothelial disorder and the most common cause of Corneal Transplantation worldwide. Professor Ernst Fuchs described the first 13 c...

  • trends in Corneal Transplantation from 2001 to 2016 in germany a report of the dog section cornea and its keratoplasty registry
    American Journal of Ophthalmology, 2018
    Co-Authors: Elias Flockerzi, Claus Cursiefen, Friedrich E Kruse, Philip Maier, Daniel Bohringer, H Reinshagen, Thomas Reinhard, Gerd Geerling, N Torun, Berthold Seitz
    Abstract:

    Purpose The purpose of this retrospective panel study was to provide an overview of absolute numbers and of trends in the types of and indications for Corneal Transplantation in Germany from 2001 to 2016. Methods A questionnaire about absolute numbers, types of Transplantation, and indications was sent to 111 ophthalmologic departments in Germany, out of which 94 (85%) provided their data. Results Since the year 2001, the number of Corneal Transplantations has increased by 1.5-fold, from 4730 penetrating keratoplasties (PKPs) in 2001 to 7325 penetrating and lamellar keratoplasties in 2016. The shift from penetrating to lamellar procedures began in 2006. In 2014, lamellar procedures (231 [4%] anterior and 2883 [49%] posterior lamellar keratoplasties) surpassed PKPs (2721, 47%) for the first time. Main indications for keratoplasty in Germany (2016) are Fuchs endothelial Corneal dystrophy (46%), pseudophakic Corneal decompensation (bullous keratopathy, 13%), repeated keratoplasty after graft failure (11%), keratoconus (8%), and Corneal scarring (6%; others: 16%). The number of Descemet membrane endothelial keratoplasties (DMEKs) was 12 times higher (3850, 53%) than Descemet stripping automated endothelial keratoplasties (DSAEKs, 319, 4.4%) in 2016. The proportion of deep anterior lamellar keratoplasties (DALKs) never exceeded 6% (269 in 2011). Conclusions The number of keratoplasties in Germany has increased from 2001 to 2016. Since 2014, posterior lamellar keratoplasties have surpassed PKPs. There was a constant increase of DMEKs, with a 12-fold higher number compared to DSAEKs in 2016. The shorter recovery time after DMEK seems to contribute to the trend toward earlier operative intervention in Corneal endothelial diseases.

  • promotion of graft survival by vascular endothelial growth factor a neutralization after high risk Corneal Transplantation
    Archives of Ophthalmology, 2008
    Co-Authors: Bjoern O Bachmann, Claus Cursiefen, Reza Dana, F Bock, Stanley J Wiegand, Kazuichi Maruyama, Friedrich E Kruse, Elke Luetjendrecoll
    Abstract:

    Objective To evaluate whether hemangiogenesis, lymphangiogenesis, and concomitant invasion of mononuclear phagocytes occurring after high-risk Corneal Transplantation in already vascularized high-risk recipient Corneal beds increase the risk for subsequent immune rejection. Methods Three intrastromal sutures were left in place for 6 weeks in the corneas of BALB/c mice, causing neovascularization. Three weeks after suture removal, keratoplasty was performed (donors C57BL/6 mice). The treatment group received a vascular endothelial growth factor A (VEGF-A)–neutralizing cytokine trap at 0, 4, 7, and 14 days postoperatively (Fc protein was used as the control treatment). Morphometry was performed in Corneal flat mounts using lymphatic endothelial hyaluronan receptor-1 (a specific lymphatic endothelial marker), CD31 (a panendothelial marker), and F4/80 (a marker for mononuclear phagocytes). Results After Corneal Transplantation, significant additional hemangiogenesis (mean area covered by vessels [SD], 68% [18%] postoperatively vs 40% [18%] preoperatively; P  = .03) and lymphangiogenesis (12% [1.3%] postoperatively vs 9% [2.8%] preoperatively; P  = .03) were observed. Postoperative neutralization of VEGF-A inhibited operation-induced hemangiogenesis (35% [8%]; P  = .007) and lymphangiogenesis (6% [1.6%]; P  = .03) and decreased the recruitment of mononuclear phagocytes into the graft (mean [SD], 501 cells/mm 2 [152] in treated mice vs 684 cells/mm 2 [35] in Fc controls; P  = .03). After 8 weeks, 23% of the treated corneas were not rejected, whereas all control corneas were rejected after 21 days ( P  = .007). Conclusions Neutralization of VEGF-A after high-risk Corneal Transplantation effectively inhibits postoperative hemangiogenesis, lymphangiogenesis, and recruitment of antigen-presenting cells and improves Corneal graft survival. Clinical Relevance Blocking of VEGF-A after high-risk Corneal Transplantation may be a novel approach to improve graft survival.

Charles Nj Mcghee - One of the best experts on this subject based on the ideXlab platform.

  • Peripheral Cornea Crosslinking Before Deep Anterior Lamellar Keratoplasty
    International Virtual Ophthalmic Research Center (IVORC), 2020
    Co-Authors: Ziaei Mohammed, Gokul Akilesh, Vellara Hans, Patel Dipika, Charles Nj Mcghee
    Abstract:

    Since Cornea crosslinking (CXL) has been proven to halt progression and biomechanically stabilize keratoconus, we hypothesized that CXL of the Corneal periphery 3 months prior to Corneal Transplantation can reduce the incidence of recurrent ectasia by strengthening the peripheral Corneal tissue and causing apoptosis of diseased peripheral host keratocytes. Thus, the aim of this case-repot was to propose a novel peripheral CXL technique prior to keratoplasty and evaluate its safety. A 22-year-old woman was admitted with advanced right keratoconus and corrected distance visual acuities of 20/30 in the right eye and 20/200 in the left eye with a manifest refraction of -3.00 -8.00 × 36 and -17.00 -11.50 × 90, respectively. The proposed treatment involved crosslinking of peripheral Corneal tissue (6.5-9.5mm), sparing the central cornea and limbus, three months prior to Corneal Transplantation as a means of biomechanically strengthening the peripheral cornea tissue. We performed peripheral CXL technique in a patient with keratoconus undergoing deep anterior lamellar keratoplasty (DALK). This procedure was feasible and safe with repopulation of the peripheral cornea with keratocytes and no significant endothelial cell loss. This method might reduce or eliminate the need for repeat Corneal Transplantation in patients with recurrent ectasia. Further studies are needed to confirm the results

  • a brief history of Corneal Transplantation from ancient to modern
    Oman Journal of Ophthalmology, 2013
    Co-Authors: Alexandra X Crawford, Dipika V Patel, Charles Nj Mcghee
    Abstract:

    This review highlights many of the fundamental concepts and events in the development of Corneal Transplantation - from ancient times to modern. Tales of eye, limb, and even heart Transplantation appear in ancient and medieval texts; however, in the scientific sense, the original concepts of Corneal surgery date back to the Greek physician Galen (130-200 AD). Although proposals to provide improved Corneal clarity by surgical interventions, including keratoprostheses, were better developed by the 17(th) and 18(th) centuries, true scientific and surgical experimentation in this field did not begin until the 19(th) century. Indeed, the success of contemporary Corneal Transplantation is largely the result of a culmination of pivotal ideas, experimentation, and perseverance by inspired individuals over the last 200 years. Franz Reisinger initiated experimental animal Corneal Transplantation in 1818, coining the term "keratoplasty". Subsequently, Wilhelmus Thorne created the term Corneal transplant and 3 years later Samuel Bigger, 1837, reported successful Corneal Transplantation in a gazelle. The first recorded therapeutic Corneal xenograft on a human was reported shortly thereafter in 1838-unsurprisingly this was unsuccessful. Further progress in Corneal Transplantation was significantly hindered by limited understanding of antiseptic principles, anesthesiology, surgical technique, and immunology. There ensued an extremely prolonged period of debate and experimentation upon the utility of animal compared to human tissue, and lamellar versus penetrating keratoplasty. Indeed, the first successful human Corneal transplant was not performed by Eduard Zirm until 1905. Since that first successful Corneal transplant, innumerable ophthalmologists have contributed to the development and refinement of Corneal Transplantation aided by the development of surgical microscopes, refined suture materials, the development of eye banks, and the introduction of corticosteroids. Recent developments, including the replacement of selected Corneal layers rather than full-thickness keratoplasty, have the potential to improve or transform Corneal transplant surgery in the future.

  • trends in the distribution of donor Corneal tissue and indications for Corneal Transplantation the new zealand national eye bank study 2000 2009
    Clinical and Experimental Ophthalmology, 2012
    Co-Authors: William J Cunningham, Nigel H Brookes, Helen C Twohill, David Pendergrast, Joanna Stewart, Louise S Moffatt, Charles Nj Mcghee
    Abstract:

    Background:  To investigate the indications for Corneal Transplantation and the distribution of donor Corneal tissue in New Zealand. Design:  Analysis of the prospective database of the New Zealand National Eye Bank. Participants:  A total of 2205 Corneal transplants were assessed. Methods:  New Zealand National Eye Bank records were analysed for the decade 2000–2009. Main Outcome Measures:  Variables analysed included donor Corneal tissue distribution (including public and private sectors), indications for Transplantation, donor Corneal tissue recipient demographics (age and gender) and Corneal Transplantation type. Results:  An average of 220 Corneal transplants were performed each year over the 10-year period (n = 2205). The median recipient age was 45 years (range 3 to 102 years) and 54.0% of recipients were male. In total 71.8% of transplants were performed in the public health sector. Surgeons in the Auckland metropolitan area performed 47.2% of all Corneal transplants. The most common indications for Corneal Transplantation were: keratoconus (41.1%), repeat transplant (17.0%), aphakic/pseudophakic bullous keratopathy (13.9%), Corneal dystrophy (10.7%), keratitis (7.9%) and trauma (3.7%). Overall, penetrating keratoplasty accounted for 90.7% of all Corneal transplants, however, during the latter half of the study there was a progressive shift in Transplantation type, with deep anterior lamellar keratoplasty and Descemet's stripping endothelial keratoplasty combined accounting for 32.3% of all transplants in the final year of the study period. Conclusions:  This New Zealand National Eye Bank study provides valuable data regarding the indications for Corneal Transplantation, transplant recipient demographics and changes in Transplantation type in New Zealand over the past decade.

  • Corneal innervation and cellular changes after Corneal Transplantation an in vivo confocal microscopy study
    Investigative Ophthalmology & Visual Science, 2007
    Co-Authors: Rachael L Niederer, Divya Perumal, Trevor Sherwin, Charles Nj Mcghee
    Abstract:

    PURPOSE. Although penetrating keratoplasty is generally considered a successful procedure, transplanted Corneal tissue may exhibit abnormal epithelium, decreased sensation, and declining endothelial cell counts after surgery. This study aimed to use in vivo confocal microscopy to correlate Corneal microstructure and recovery of the subbasal nerve plexus of the transplanted cornea with indications for, and time from, surgery. METHODS. This was a cross-sectional study comparing corneas from 42 patients after penetrating keratoplasty with those of 30 controls. Subjects were assessed by ophthalmic history and clinical examination, computerized Corneal topography, and laser scanning in vivo confocal microscopy. RESULTS. Time from surgery ranged from 1 month to 40 years (mean, 85 105 months). Significant reductions in epithelial (P 0.001), keratocyte (P 0.001), and endothelial (P 0.001) cell densities were noted in comparison with control corneas. Significant reductions in subbasal nerve fiber density (P 0.001) and nerve branching (P 0.001) were also noted. Endothelial cell density decreased with time after surgery (r ‐0.472; P 0.003), and nerve fiber density (r .328; P 0.034) increased. Keratoconus as an indication for Transplantation was associated with higher subbasal nerve fiber densities (P 0.003) than other indications for Corneal Transplantation. Neither nerve fiber nor cell density was correlated with bestcorrected visual acuity. CONCLUSIONS. Laser scanning in vivo confocal microscopy highlights profound reductions in cell density at every level of the transplanted cornea and alterations to the subbasal plexus that are still apparent up to 40 years after penetrating keratoplasty. (Invest Ophthalmol Vis Sci. 2007;48:621‐626) DOI:10.1167/ iovs.06-0538

Shimon Rumelt - One of the best experts on this subject based on the ideXlab platform.

Jerry Y Niederkorn - One of the best experts on this subject based on the ideXlab platform.

  • Corneal Transplantation and immune privilege
    International Reviews of Immunology, 2013
    Co-Authors: Jerry Y Niederkorn
    Abstract:

    Corneal transplants have been successfully performed in human subjects for over 100 years and enjoy an immune privilege that is unrivaled in the field of Transplantation. Immune privilege is defined as the reduced incidence and tempo in the immune rejection of Corneal allografts compared to other categories of organ allografts performed under the same conditions. Skin allografts transplanted across various MHC or minor histocompatibility barriers undergo rejection in approximately 100% of the hosts. By contrast, orthotopic Corneal allografts experience long-term survival in 50% to >90% of the hosts, depending on the histocompatibility barriers that confront the host. The capacity of Corneal allografts to evade immune rejection is attributable to multiple anatomical, physiological and immunoregulatory conditions that conspire to prevent the induction and expression of alloimmunity.

  • immunology and immunomodulation of Corneal Transplantation
    International Reviews of Immunology, 2002
    Co-Authors: Jerry Y Niederkorn
    Abstract:

    Corneal allografts are the oldest, most common, and most successful transplants performed on humans and animals. The cornea is endowed with a constellation of unique factors that contribute to its immune privilege and the low incidence of immune rejection. In spite of this immune privilege, 10 percent of first-time Corneal grafts will undergo immune rejection. Several novel therapeutic strategies hold promise for modulating the alloimmune response by either promoting antigen-specific tolerance or redirecting the host's response from a Th1 pathway toward a Th2 pathway.

Edward J Holland - One of the best experts on this subject based on the ideXlab platform.

  • attenuation of ocular hypertension with the use of topical loteprednol etabonate 0 5 in steroid responders after Corneal Transplantation
    Cornea, 2009
    Co-Authors: Edward J Holland, Ali R Djalilian, Jeffrey P Sanderson
    Abstract:

    Purpose To describe a clinically observed reduction in intraocular pressure (IOP) without increased allograft rejection in known "steroid responders" using loteprednol etabonate 0.5% ophthalmic suspension as second-line rescue therapy after Corneal Transplantation. Methods Medical records from a prespecified 15-month period were retrospectively reviewed for all post-Corneal transplant patients in whom loteprednol etabonate was initiated and prednisolone acetate 1.0% ophthalmic suspension withdrawn because of a secondary increase in IOP. Elevated postoperative IOP was defined as IOP that increased > or =21 mm Hg. Baseline IOP values were compared with IOP readings at follow-up examinations, with data points set retrospectively at 0-4, 4-8, 8-16, 16-32, and >32 weeks. Patient records were evaluated for any signs of allograft rejection during loteprednol etabonate therapy. Results Thirty patients were found to have switched to loteprednol etabonate after an increase in IOP during postoperative prednisolone acetate treatment. The mean reduction in IOP observed when comparing initial and final values in all 30 patients was 12.9 mm Hg during a mean follow-up of 21.6 weeks. The mean percent reduction in IOP during loteprednol etabonate treatment was 32.6% at 3 weeks and 44.9% at 39 weeks. No clinically observed signs of allograft rejection were documented. Conclusions Switching to loteprednol etabonate from prednisolone acetate in known steroid responders was successful in reducing IOP and did not increase the risk of allograft rejection. Because of its lower potential for causing elevated IOP, loteprednol etabonate should be considered in the prophylaxis of allograft rejection in steroid responders.

  • donor age and Corneal endothelial cell loss 5 years after successful Corneal Transplantation specular microscopy ancillary study results
    Ophthalmology, 2008
    Co-Authors: Jonathan H Lass, Edward J Holland, Mariya Dontchev, Roy W Beck, Craig Kollman, Steven P Dunn, Ellen Heck, Mark J Mannis, Monty Montoya, Robert L Schultze
    Abstract:

    OBJECTIVE: To determine whether endothelial cell loss 5 years after successful Corneal Transplantation is related to the age of the donor. DESIGN: Multicenter, prospective, double-masked clinical trial. PARTICIPANTS: Three hundred forty-seven subjects participating in the Cornea Donor Study who had not experienced graft failure 5 years after Corneal Transplantation for a moderate-risk condition (principally Fuchs' dystrophy or pseudophakic Corneal edema). TESTING: Specular microscopic images of donor corneas obtained before surgery and postoperatively at 6 months, 12 months, and then annually through 5 years were submitted to a central reading center to measure endothelial cell density (ECD). MAIN OUTCOME MEASURE: Endothelial cell density at 5 years. RESULTS: At 5 years, there was a substantial decrease in ECD from baseline for all donor ages. Subjects who received a cornea from a donor 12 to 65 years old experienced a median cell loss of 69% in the study eye, resulting in a 5-year median ECD of 824 cells/mm(2) (interquartile range, 613-1342), whereas subjects who received a cornea from a donor 66 to 75 years old experienced a cell loss of 75%, resulting in a median 5-year ECD of 654 cells/mm(2) (interquartile range, 538-986) (P [adjusted for baseline ECD] = 0.04). Statistically, there was a weak negative association between ECD and donor age analyzed as a continuous variable (r [adjusted for baseline ECD] = -0.19; 95% confidence interval, -0.29 to -0.08). CONCLUSIONS: Endothelial cell loss is substantial in the 5 years after Corneal Transplantation. There is a slight association between cell loss and donor age. This finding emphasizes the importance of longer-term follow-up of this cohort to determine if this relationship affects graft survival.

  • the effect of donor age on Corneal Transplantation outcome results of the cornea donor study
    Ophthalmology, 2008
    Co-Authors: Robin L Gal, Edward J Holland, Jonathan H Lass, Mariya Dontchev, Roy W Beck, Craig Kollman, Steven P Dunn, Ellen Heck, Mark J Mannis, Monty M Montoya
    Abstract:

    OBJECTIVE To determine whether graft survival over a 5-year follow-up period using Corneal tissue from donors older than 65 is similar to graft survival using corneas from younger donors. DESIGN Multicenter prospective, double-masked, controlled clinical trial. PARTICIPANTS One thousand ninety subjects undergoing Corneal Transplantation for a moderate-risk condition (principally Fuchs' dystrophy or pseudophakic Corneal edema); 11 subjects with ineligible diagnoses were not included. METHODS Forty-three participating eye banks provided corneas from donors in the age range of 12 to 75 with endothelial cell densities of 2300 to 3300 cells/mm(2), using a random approach without respect to recipient factors. The 105 participating surgeons at 80 sites were masked to information about the donor cornea including donor age. Surgery and postoperative care were performed according to the surgeons' usual routines. Subjects were observed for 5 years. MAIN OUTCOME MEASURES Graft failure, defined as a regraft or a cloudy cornea that was sufficiently opaque as to compromise vision for a minimum of 3 consecutive months. RESULTS The 5-year cumulative probability of graft survival was 86% in both the /=66.0 donor age group (difference = 0%, upper limit of 1-sided 95% confidence interval = 4%). In a statistical model with donor age as a continuous variable, there was no significant relationship between donor age and outcome (P = 0.11). Three graft failures were due to primary donor failure, 8 to uncorrectable refractive error, 48 to graft rejection, 46 to endothelial decompensation (23 of which had a prior, resolved episode of probable or definite graft rejection), and 30 to other causes. Distributions of the causes of graft failure did not differ between donor age groups. CONCLUSIONS Five-year graft survivals for cornea transplants at moderate risk for failure are similar using corneas from donors >/= 66.0 years and donors < 66.0. Surgeons and patients now have evidence that corneas comparable in quality to those used in this study from donors through age 75 are suitable for Transplantation.