Trends of Corneal Transplantation in Adults from 2010 to 2019 in East China: A 10-Year Experience.

INTRODUCTION: The aim of the study was to provide an overview of trends in the indications and surgical techniques for corneal transplantation in adults in East China from 2010 to 2019. METHODS: The medical charts of all patients (aged ≥18 years old) undergoing keratoplasty at the Eye, Ear, Nose and Throat Hospital of Fudan University between January 2010 and December 2019 were retrospectively reviewed. The indications for keratoplasty and the surgical techniques were collected. RESULTS: A total of 2,929 cases were included. Acquired nontraumatic corneal diseases (n = 1,927, 65.8%) have been the leading indication for corneal transplantation during the past decade. Although infectious keratitis was still the leading indication among acquired nontraumatic diseases, its absolute number and proportion gradually decreased during this decade (p < 0.001). In contrast, the proportion of endothelial dysfunction/bullous keratopathy increased from 7.8% in 2010 to 12.4% in 2019 (p = 0.029). Penetrating keratoplasty (PKP) has been the predominant surgical technique (n = 1,854, 63.3%), followed by deep anterior lamellar keratoplasty (DALK) (n = 361, 12.3%) and endothelial keratoplasty (EK) (n = 305, 10.4%). Nevertheless, the proportion of PKP decreased from 77.6% in 2010 to 56.9% in 2019 (p = 0.002) and was gradually replaced by DALK (from 7.8% to 16.3%, p < 0.001) and EK (from 3.4% to 10.4%, p = 0.009). CONCLUSIONS: Over the past decade, infectious keratitis and endothelial dysfunction/bullous keratopathy have been the leading indications for keratoplasty in adults. Preferred surgical techniques for keratoplasty have been shifting from PKP to more customized lamellar keratoplasties.

New Therapies for Corneal Endothelial Diseases: 2020 and Beyond.

ABSTRACT: Penetrating keratoplasty used to be the only surgical technique for the treatment of end-stage corneal endothelial diseases. Improvements in surgical techniques over the past decade have now firmly established endothelial keratoplasty as a safe and effective modality for the treatment of corneal endothelial diseases. However, there is a worldwide shortage of corneal tissue, with more than 50% of the world having no access to cadaveric tissue. Cell injection therapy and tissue-engineered endothelial keratoplasty may potentially offer comparable results as endothelial keratoplasty while maximizing the use of cadaveric donor corneal tissue. Descemet stripping only, Descemet membrane transplantation, and selective endothelial removal are novel therapeutic modalities that take this a step further by relying on endogenous corneal endothelial cell regeneration, instead of allogenic corneal endothelial cell transfer. Gene therapy modalities, including antisense oligonucleotides and clustered regularly interspaced short palindromic repeats-based gene editing, offer the holy grail of potentially suppressing the phenotypic expression of genetically determined corneal endothelial diseases at the asymptomatic stage. We now stand at the crossroads of exciting developments in medical technologies that will likely revolutionize the way we treat corneal endothelial diseases over the next 2 decades.

Trends in corneal transplantation in a single center in Barcelona, Spain. Transitioning to DMEK.

PURPOSE: To observe trends in surgical techniques for corneal transplantation and main indications in our hospital over the past five years. METHODS: Retrospective descriptive study, including all keratoplasties performed at the Hospital Clinic of Barcelona, Spain, between January 2014 and December 2018. RESULTS: In total, 332 keratoplasties were performed. In total, 127 (38.25%) were penetrating keratoplasties (PK), and 205 (61.75%) were lamellar keratoplasties (LK). In 2014, a total of 48 keratoplasties were carried-out, whereas in 2018, the total was 93, which represents a 93.75% increase in corneal transplantation surgeries. Eye bank-delivered precut tissue for DMEK was introduced in 2016, and 3 cases (6.25%), were carried out that year. In 2018, DMEK became the leading technique with 56 cases (60.22%). Fuchs' dystrophy was the leading indication for corneal transplant (37.63%) in 2018. CONCLUSION: Introduction of DMEK in a single center can be implemented in a relatively short period of time, becoming the most popular surgical procedure in corneal transplantation. A possible factor encouraging this change is the availability of eye bank-delivered precut tissue, and standardization of donor preparation and host surgical steps, optimizing surgical time in the operating room. This trend should lead to better visual outcomes, faster recovery times, and eventually to a higher surgical volume per year.

The Rapid Transformation of Transplantation for Corneal Endothelial Diseases: An Evolution From Penetrating to Lamellar to Cellular Transplants.

The cornea is the major focusing structure of the human eye and the corneal endothelium maintains the relatively dehydrated state of the cornea required for clarity. The endothelial cells respond to disease or injury by migration and cellular enlargement. Our current understanding is that there is a very limited degree of proliferative or regenerative capacity in the human corneal endothelium. Thus, corneal endothelial diseases may result in corneal edema, significantly impact vision and quality of life. Contemporary surgical transplantation options for treating moderate to advanced endothelial dysfunction include penetrating keratoplasty (PK), Descemet stripping endothelial keratoplasty (DSEK), and Descemet membrane endothelial keratoplasty. Advances in surgical techniques aim to bring faster visual recovery and improve visual outcomes; however, there is still a significant donor cornea shortage worldwide and alternative methods for treatment for corneal endothelial disease are rapidly evolving. Indeed, we are at a pivotal point in corneal transplantation for endothelial disease and novel surgical strategies include using 1 donor for multiple recipients, a minimally attached endothelial graft, and Descemet membrane stripping only. Crucially, forthcoming approaches include the use of Rho-Kinase (ROCK) inhibitors, endothelial cell therapy, tissue engineered grafts, and consideration of stem cell techniques. Ultimately, the choice of technique will be dependent on recipient factors such as age, type of endothelial disease, extent of the disease, and associated ocular disorders. The safety and efficacy of these rapidly developing treatments warrant further investigations. In time, some or all of these alternatives for corneal transplantation will alleviate the reliance on limited corneal donor tissue.

Corneal transplantation in the modern era.

Corneal blindness is one of the major causes of reversible blindness, which can be managed with transplantation of a healthy donor cornea. It is the most successful organ transplantation in the human body as cornea is devoid of vasculature, minimizing the risk of graft rejection. The first successful transplant was performed by Zirm, and since then, corneal transplantation has seen significant evolution. It has been possible because of the relentless efforts by researchers and the increase in knowledge about corneal anatomy, improvement in instruments and advancements in technology. Keratoplasty has come a long way since the initial surgeries wherein the whole cornea was replaced to the present day where only the selective diseased layer can be replaced. These newer procedures maintain structural integrity and avoid catastrophic complications associated with open globe surgery. Corneal transplantation procedures are broadly classified as full-thickness penetrating keratoplasty and partial lamellar corneal surgeries which include anterior lamellar keratoplasty [sperficial anterior lamellar keratoplasty (SALK), automated lamellar therapeutic keratoplasty (ALTK) and deep anterior lamellar keratoplasty (DALK)] and posterior lamellar keratoplasty [Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK)] broadly.

The future of keratoplasty: cell-based therapy, regenerative medicine, bioengineering keratoplasty, gene therapy.

PURPOSE OF REVIEW: To provide an update on the state of development of novel therapeutic modalities for the treatment of corneal diseases. RECENT FINDINGS: Novel corneal therapeutics may be broadly classified as cell therapy, regenerative medicine, bioengineered corneal grafts and gene therapy. Cell therapy encompasses cultivation of cells, such as corneal endothelial cells (CECs) and keratocytes to replenish the depleted native cell population. Regenerative medicine is mainly applicable to the corneal endothelium, and is dependent on the ability of native, healthy CECs to restore the corneal endothelium following trauma or descemetorhexis; this approach may be effective for the treatment of Peter's anomaly and Fuchs endothelial corneal dystrophy (FECD). Bioengineered corneal grafts are synthetic constructs designed to replace cadaveric corneal grafts; tissue-engineered endothelial-keratoplasty grafts and bioengineered stromal grafts have been experimented in animal models with favourable results. Gene therapy with antisense oligonucleotide and CRISPR endonucleases, including deactivated Cas9, may potentially be used to treat FECD and TGFBI-related corneal dystrophies. SUMMARY: These novel therapeutic modalities may potentially supersede keratoplasty as the standard of care in the future.

Recent Surgical Trends in Pediatric Corneal Transplantation: A 13-Year Review.

PURPOSE: Corneal transplantation is the standard of care for pediatric corneal opacities, but little consensus exists on optimal surgical management. Our goal was to evaluate cross-sectional data of donor and recipient characteristics collected from eye banks providing tissue for pediatric corneal transplant cases to assess surgical trends in pediatric keratoplasty over the past 13 years. METHODS: We performed a retrospective review of recipient data, collected from 4 major eye banks, for pediatric patients (<18 years) who underwent corneal transplantation between January 2005 and December 2017. We analyzed trends in surgical indications, types of keratoplasty, and donor/recipient characteristics. RESULTS: Our database included 2620 total pediatric cases. Penetrating keratoplasty (PKP) remains the most common surgery performed (79.8%), but more partial-thickness transplant cases [eg, endothelial keratoplasty (EK)] have been performed since 2008. The most commonly reported transplant indication was ectasias/thinnings (34.1%) overall and congenital opacities (17.0%) in children less than 5 years. Average donor age was significantly lower for the youngest recipient age group of less than 5 years (P < 0.001); endothelial cell count was also higher, and death-to-surgery time was lower for PKP and EK cases versus other keratoplasties. CONCLUSIONS: Indications for transplant vary across age groups but are consistent with previous reports. Popularity of partial-thickness transplants has increased since 2008. Surgeons prefer younger donor tissue for younger patients and have higher thresholds for endothelial cell count for PKP and EK cases. Centralized tracking of pediatric keratoplasty cases is necessary for further investigation of long-term outcomes.

New trends in corneal transplants at the University of Toronto.

OBJECTIVE: To assess trends in surgical procedures and indications for all corneal transplants performed at the University of Toronto. DESIGN: Retrospective cross-sectional study. PARTICIPANTS: One thousand one hundred and four consecutive corneal transplants performed at the Kensington Eye Institute (KEI). METHODS: Demographic, clinical, and pathological data retrieved from the Ophthalmic Pathology Laboratory on all corneal transplants performed at the KEI from January 2014 to December 2016. RESULTS: Over 3 years, partial-thickness lamellar keratoplasties were performed in 880 cases (80%) while full-thickness penetrating keratoplasties (PKP) accounted for 224 cases (20%). Leading causes of corneal transplant were Fuchs' dystrophy (42%), graft failure (17%), bullous keratopathy (15%), and keratoconus (15%). Graft failure (40%) and keratoconus (31%) were the leading causes for PKP. Descemet's membrane endothelial keratoplasty (DMEK) accounted for 37% of cases, Descemet's stripping automated endothelial keratoplasty (DSAEK) for 30%, and deep anterior lamellar keratoplasty (DALK) for 13%. By 2016, partial-thickness procedures had increased by 10%, accounting for 85% of all procedures. In addition, DMEK increased by 26%, DSAEK decreased by 13%, and PKP decreased by 11%. Fuchs' dystrophy remained the leading indication for DMEK (67%) and DSAEK (42%) procedures. In 2016, 73% of DALK procedures were for the treatment of keratoconus. CONCLUSIONS: Partial-thickness corneal transplants now account for 85% of all current graft procedures, and DMEK has emerged as the procedure of choice. Graft failure continues to be the leading indication for full-thickness grafts. Longitudinal studies are needed to determine whether these new trends persist and their future impact on graft failures.

Trends in corneal transplantation from 2001 to 2016 in Brazil / Tendências no transplante de córnea de 2001 a 2016 no Brasil

ABSTRACT A retrospective and analytical study was conducted by using data from the National Transplantation System on 184,575 corneal transplantations performed between January 2001 and December 2016 in order to analyze thetrends in corneal transplantation from 2001 to 2016 in Brazil. The Cochran-Armitage test, analysis of variance, and Duncan's multiple comparisons were used to verify the existence of trends, compare the mean values between regions, and verify the mean differences, respectively. A significance level of 5% was used for all tests. The analysis showed that there was a 2.4-fold increase in the number of corneal transplantations (from 6,193 [35.2 per million people (pmp)] to 14,641 [71 pmp]; p<0.001), a 50.7% increase in the efficacy of meeting the population's demand for corneal transplantation (from 35.3% to 53.2%; p<0.001), an 11-fold increase in the number of corneal transplantation centers (from 32 to 356), and a 2.5-fold increase in the number of corneal transplantation teams (from 276 to 688) in Brazil during the period studied. The waiting list for corneal transplantation decreased by 45.4% (from 23,549 [123 pmp] to 12,865 [62.4 pmp]; p<0.001), and the corneal transplantation teams performed about 19 corneal transplantations per year. The best indices were observed in the southern, midwestern, and southeastern regions, and the worst indices were in the northern and northeastern regions. Brazil has been improving its capacity to perform corneal transplantation in the past 16 years, although this improvement varies across regions. However, the population's demand for corneal transplantation is yet to be satisfactorily met, primarily due to the low number of corneal donations.

RESUMO Estudo retrospectivo e analítico, baseado em dados do Sistema Nacional de Transplantes de 184.575 transplantes de córnea realizados no período de janeiro de 2001 a dezembro de 2016, com o objetivo de analisar as tendências do transplante de córnea no Brasil de 2001 a 2016. Os testes de Cochran-Armitage, análise de variância e comparações múltiplas de duncan foram realizados para verificar a existência de tendência, comparação de médias entre regiões e verificação da diferença média, respectivamente. Um nível de significância de 5% foi utilizado em todos os testes. No Brasil, houve um aumento: de 2,4 vezes no número de transplantes de córnea (de 6.193 [35,2 pmp] para 14.641 [71 pmp] - p<0,001); de 50,7% na eficácia de atender a demanda populacional de transplantes de córnea (de 35,3% para 53,2% - p<0,001); de 11 vezes no número de centros de transplantes de córnea (de 32 para 356); e de 2,5 vezes no número de equipes transplantadoras de córnea (de 276 para 688). A lista de espera para o transplantes de córnea diminuiu em 45,4% (de 23.549 [123 pmp] para 12.865 [62,4 pmp] - p<0,001). A produtividade das equipes de córnea ao longo dos anos foi de 19 transplantes de córnea ao ano. Os melhores índices foram apresentados nas regiões Sul, Cen tro-Oeste e Sudeste e os piores no Norte e Nordeste. O Brasil, embora de forma heterogênea entre as regiões, vem melhorando a capacidade de realizar o transplante de córnea nos últimos 16 anos, porém a demanda populacional por transplante de córnea ainda não é adequadamente atendida, principalmente devido ao baixo número de doações de córnea.

Trends in corneal transplantation from 2001 to 2016 in Brazil.

A retrospective and analytical study was conducted by using data from the National Transplantation System on 184,575 corneal transplantations performed between January 2001 and December 2016 in order to analyze thetrends in corneal transplantation from 2001 to 2016 in Brazil. The Cochran-Armitage test, analysis of variance, and Duncan's multiple comparisons were used to verify the existence of trends, compare the mean values between regions, and verify the mean differences, respectively. A significance level of 5% was used for all tests. The analysis showed that there was a 2.4-fold increase in the number of corneal transplantations (from 6,193 [35.2 per million people (pmp)] to 14,641 [71 pmp]; p<0.001), a 50.7% increase in the efficacy of meeting the population's demand for corneal transplantation (from 35.3% to 53.2%; p<0.001), an 11-fold increase in the number of corneal transplantation centers (from 32 to 356), and a 2.5-fold increase in the number of corneal transplantation teams (from 276 to 688) in Brazil during the period studied. The waiting list for corneal transplantation decreased by 45.4% (from 23,549 [123 pmp] to 12,865 [62.4 pmp]; p<0.001), and the corneal transplantation teams performed about 19 corneal transplantations per year. The best indices were observed in the southern, midwestern, and southeastern regions, and the worst indices were in the northern and northeastern regions. Brazil has been improving its capacity to perform corneal transplantation in the past 16 years, although this improvement varies across regions. However, the population's demand for corneal transplantation is yet to be satisfactorily met, primarily due to the low number of corneal donations.

Trends in corneal transplantation at the University Eye Hospital in Tübingen, Germany over the last 12 years: 2004 - 2015.

PURPOSE: This study aimed to investigate the trends in the surgical methods and leading indications for corneal transplantations carried out over the last 12 years. METHODS: The data from the corneal graft waiting list and from all keratoplasties carried out between 2004 and 2015 at the University Eye Hospital in Tübingen were retrospectively analyzed. RESULTS: A total of 1,185 keratoplasties were performed between 2004 and 2015 at this hospital. The most common surgical indications for corneal transplantation were Fuchs' endothelial corneal dystrophy (35.2%) and keratoconus (18.9%) with keratoconus being the leading cause during early years (from 2004 to 2009) and Fuch's dystrophy being the leading cause from 2010 to 2015. Overall, the total count of performed keratoplasties increased, from 385 corneal transplantations during the first 6-year period to 800 corneal transplantations during the second 6-year period (P = 0.008, using Mann-Whitney test). The Descemet's membrane endothelial keratoplasty has become the favored surgical method for endothelial disorders with the number of Descemet's membrane endothelial keratoplasties increasing significantly from 2008 to 2015. This increasing trend was statistically significant (P < 0.001 using multivariate adaptive regression splines (MARS). A decreasing trend was also noted for the rate of penetrating keratoplasty since 2008 (P < 0.001 using MARS). CONCLUSIONS: This research showed major changes in the preferred corneal transplantation techniques and leading indications for keratoplasty over the last 12 years. More importantly, it seems that the rapid development and implementation of endothelial keratoplasty, especially the Descemet's membrane endothelial keratoplasty, has had a profound effect on and begun a new era in corneal transplantation.

Corneal transplantation trends in France from 2004 to 2015: A 12-year review.

PURPOSE: The aim of this study was to report the 12-year longitudinal trends in indication and corneal transplantation techniques in France from 2004 to 2015. RESULTS: The records of all corneal transplantations performed from 2004 to 2015 in France were retrospectively reviewed. The patient indications and types of transplant performed were analyzed. A total of 46,658 corneal transplantations were performed between 2004 and 2015, with 34,187 (73.3%) penetrating keratoplasty and 10,452 (22.4%) lamellar keratoplasty. The leading surgical indications were secondary endothelial failure (24.3%), keratoconus (18.8%), regraft (13.5%), and Fuchs endothelial corneal dystrophy (15.1%). Endothelial keratoplasty became the preferred technique for endothelial diseases and deep anterior lamellar keratoplasty the preferred technique for keratoconus, surpassing penetrating keratoplasty in 2013. CONCLUSION: Secondary endothelial failure is the top indication for performing a keratoplasty over the 12-year period. There was a shift from penetrating keratoplasty to endothelial keratoplasty performed for Fuchs endothelial corneal dystrophy and secondary endothelial failure, and to deep anterior lamellar keratoplasty, performed for keratoconus. This highlights an important shift in managing corneal diseases toward the application of selective and more conservative surgeries and changes in indications in corneal transplantation.

Trends in Corneal Transplantation from 2001 to 2016 in Germany: A Report of the DOG-Section Cornea and its Keratoplasty Registry.

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.

Trends in corneal transplant surgery in Ireland: indications and outcomes of corneal transplant surgery and intraocular lens opacification following Descemet's stripping automated endothelial keratoplasty.

PURPOSE: To evaluate the indications for corneal transplantation, the procedures carried out, and the postoperative outcomes and to compare these with previous Irish corneal transplant studies. METHODS: A retrospective review of the case notes of all patients who underwent corneal transplantation under the care of a single surgeon, from 2008 to 2015, was performed. The risk factors for postoperative complications including transplant failure were examined. RESULTS: During the period studied, 42 corneal transplant surgeries were carried out on 40 eyes of 38 patients, 24 of whom were male (63%), median age at surgery was 62 years (range 23-96 years). The most common indication for transplantation was pseudophakic corneal decompensation associated with Fuch's endothelial dystrophy (FED) (n = 13). Seventeen penetrating keratoplasties, 23 lamellar keratoplasties, and two amniotic membrane transplant procedures were carried out. Transplant failure resulting in corneal oedema or repeat corneal transplant surgery (n = 4, 10%), was associated with previous transplant failure in the eye; odds ratio (OR) = 1.58 (p = 0.05), and with comorbid FED, OR = 1.50 (p = 0.02). Intraocular lens opacification occurred in one lens following DSAEK, giving an incidence rate of 7%. CONCLUSIONS: Pseudophakic corneal decompensation is the commonest indication for corneal transplant surgery, with lamellar keratoplasty the most frequent approach in our cohort, reflecting developments observed in corneal transplant surgery elsewhere. Prior corneal transplant failure and Fuch's dystrophy remain important risk factors for failure. The risk of intraocular lens opacification and its potential effects on vision should be elaborated prior to endothelial keratoplasty.

The Evolution of Corneal Transplantation.

BACKGROUND The aim of this study was to investigate the evolution of surgical methods in and leading indications for corneal transplantation from 2005 to 2016. MATERIAL AND METHODS Data from the corneal graft waiting list and from all keratoplasties carried out between 2005 and 2016 at the University Eye Hospital Tübingen were retrospectively evaluated. RESULTS A total of 1259 keratoplasties were performed between 2005 and 2016 at the University Eye Hospital Tübingen. The most common surgical indications for corneal transplantation were Fuchs endothelial corneal dystrophy (45.5%) and keratoconus (14.2%). The mean rate of corneal transplantations almost doubled from 71 keratoplasties per year in the first 6-year period to 139 keratoplasties per year in the second 6-year period (P=0.005). The number of penetrating keratoplasties remained similar. The number of Descemet membrane endothelial keratoplasties (DMEK) increased significantly from 2008 to 2016 (P<0.0001). One DMEK procedure was performed in 2008 (representing 1.4% of all transplantations), while 75 DMEK procedures were performed in 2016 (representing 60.5% of all transplantations) (P<0.0001). DMEK became the favored surgical method for endothelial disorders, exceeding penetrating keratoplasty in 2013. CONCLUSIONS Our study shows evolutionary changes in preferred corneal transplantation techniques and leading indications for keratoplasty from 2005 to 2016. Since its introduction a decade ago, DMEK is currently the golden standard in the management of corneal endothelial dysfunction.

Component corneal surgery: An update.

Several decades ago, penetrating keratoplasty was a challenge to corneal surgeons. Constant effort by the corneal surgeon to improve the outcomes as well as utilization of the available resources has led to a revolutionary change in the field of keratoplasty. All these efforts have led to the evolution of techniques that allow a corneal surgeon to disease-specific transplant of individual layers of corneal "so-called component corneal surgery" depending on the layer of cornea affected. This has led to an improvement in corneal graft survival as well as a better utilization of corneal tissues. This article reviews the currently available literature on component corneal surgeries and provides an update on the available techniques.

EK (DLEK, DSEK, DMEK): New Frontier in Cornea Surgery.

Endothelial keratoplasty (EK) has revolutionized treatment of corneal endothelial dysfunction. Compared with penetrating keratoplasty (PK), EK provides faster and more reliable visual rehabilitation while maintaining the eye's structural integrity. The number of EK procedures is growing annually and surpassed PK in the United States in 2012. The most widely used iteration, Descemet stripping endothelial keratoplasty (DSEK), implants healthy donor endothelium, Descemet membrane, and posterior stroma. Descemet membrane endothelial keratoplasty (DMEK) eliminates the donor stromal layer. Although more surgically challenging than DSEK, DMEK provides even faster visual rehabilitation and reduced risk of immunologic rejection, so its use is growing. Potential future alternatives to EK that could help address the unmet demand for donor corneas include removing central guttae and regenerating a central endothelial cell layer from healthy peripheral cells in patients with Fuchs' dystrophy or injecting cultured human corneal endothelial cells to rehabilitate eyes without residual healthy endothelium.