Risk Factors for Repeat Keratoplasty after Endothelial Keratoplasty in the Medicare Population.

PURPOSE: To evaluate long-term rates of repeated keratoplasty after endothelial keratoplasty (EK), and to explore risk factors associated with graft failure. DESIGN: Retrospective, cohort study. METHODS: Population-based using 2010-2019 Medicare carrier claims. STUDY POPULATION: Medicare beneficiaries aged ≥65 years who underwent endothelial keratoplasty (EK) procedures. Main outcome measures were 1) occurrence of repeated keratoplasty for the overall cohort as well as stratified by clinical indication, and 2), risk factors associated with repeated keratoplasty. The probability of undergoing repeated keratoplasty for different indications was estimated using the Kaplan-Meier method and compared using the log-rank test. A Cox proportional hazards regression model was constructed to determine patient and physician factors associated with the risk of repeated keratoplasty. RESULTS: A total of 94,829 Medicare EK procedures (N = 71,040 unique patients) were included in the analysis. Over the study period, 11,013 of 94,829 EK procedures were followed by repeated keratoplasty. The overall probability of receiving a repeated keratoplasty was 6.1% at 6 months, 7.6% at 1 year, 14.3% at 5 years and 16.9% at 8 years. The probability of repeated keratoplasty was highest for procedures performed for prior failed grafts: 10.2% at 1 year, 29.9% at 8 years. Whereas 6.4% and 11.4% of grafts performed for Fuchs' endothelial dystrophy (FED) required repeated keratoplasty at 1 and 8 years of follow-up, respectively. For bullous keratoplasty and/or corneal edema, 8.6% and 22% of grafts underwent repeated keratoplasty at 1 and 8 years, respectively. In a multivariate analysis, patient factors associated with increased risk of repeated keratoplasty were black (hazard ratio [HR]: 1.29; 95% confidence interval [CI]: 1.20-1.38) or Asians (HR: 1.26; 95% CI: 1.10-1.45) having a glaucoma diagnosis (HR: 1.53; 95% CI: 1.46-1.60), prior glaucoma surgery (HR: 1.26; 95% CI: 1.18-1.35), and concurrent glaucoma surgery (HR: 1.31; 95% CI: 1.20-1.44). Surgeons with higher EK volumes had a decreased risk of repeated keratoplasty. Physicians who graduated medical school >30 years previously had increased risk of repeated keratoplasty compared to those who graduated within 10 years (HR: 1.16; 95% CI: 1.10-1.23). CONCLUSIONS: Blacks or Asians, comorbid glaucoma, concurrent or prior glaucoma surgery, and lower volumes of surgery are associated with increased risk of repeated keratoplasty. Racial disparities identified in this study warrant further investigation.

Keratoplasty Outcomes in Patients With Uveitis.

PURPOSE: To examine the corneal transplant failure rates and associations with uveitic eye disease. METHODS: The retrospective chart review identified 70 eyes from 42 patients with uveitis that underwent 40 primary transplants and 30 repeat transplants at 2 major academic centers over a 9-year period. The graft failure rate was calculated. Variables hypothesized to be associated with graft failure were analyzed as covariates using a Cox proportional hazards analysis clustered by the patients to determine their association with failure rates. RESULTS: Of the 70 grafts, the mean duration of follow-up for patients was 40.6 months (range 4-90 months) and the median survival time was 24.1 months (interquartile range of 9-290 months). Twenty-two patients (52%) had graft failure. There was a higher rate of graft failure in patients with infectious uveitis as compared to those with noninfectious uveitis (hazard ratio 2.46, P = 0.031). Patients with successful grafts had their inflammation controlled for a longer period of time before transplantation as compared to those with failed grafts (38.6 vs. 13.6 months, P = 0.004). Worse preoperative visual acuities were significantly associated with graft failure (P < 0.001). CONCLUSIONS: There is limited knowledge of corneal transplant outcomes in uveitic patients in the current literature. In our study, over half of the grafts failed. Infectious uveitis (especially viral) was a strong predictor of graft failure. A shorter period of inflammation control before transplantation, previously failed grafts, and worse preoperative visual acuity were also associated with graft failure.

Descemet Membrane Endothelial Keratoplasty for Failed Penetrating Keratoplasty: Visual Outcomes and Graft Survival.

PURPOSE: To evaluate outcomes and graft survival of Descemet membrane endothelial keratoplasty (DMEK) for failed penetrating keratoplasty (PK). METHODS: Ninety-three DMEK procedures performed in 84 eyes of 77 patients with failed PK were retrospectively reviewed. The main outcomes were corrected distance visual acuity and graft survival assessed with Kaplan-Meier survival analysis and proportional hazards modeling taking follow-up into consideration. RESULTS: Sixty-nine eyes had 1 previous failed PK, 13 had 2, 1 had 3, and 1 had 4. Ten eyes had failed Descemet stripping endothelial keratoplasty (DSEK) performed under failed PK. Fourteen cases (15%) had previous glaucoma filtration surgery (9 trabeculectomy alone; 5 trabeculectomy and aqueous shunt). Median follow-up was 21 months (range, 1 month to 7 years). Median Snellen corrected distance visual acuity improved from 20/100 preoperatively (range, 20/30 to count fingers) to 20/30 at 6 months postoperatively (n = 73; range, 20/20-20/200). Rebubbling rates were 53% when the diameter of the DMEK graft was oversized, 27% when same sized, and 33% when undersized relative to that of the previous PK graft. Two grafts (2%) experienced an immunologic rejection episode, and 15 (16%) failed, including 5 primary/early failures and 10 late failures. Previous glaucoma surgery was the only significant risk factor for failure (relative risk, 7.1; 95% confidence interval, 2.1-37.0). The 1-, 2-, and 3-year graft survival rates were 96%, 89%, and 89% without versus 78%, 53%, and 39% with previous glaucoma surgery. CONCLUSIONS: Treatment of failed PK with DMEK produced similar 4-year survival (76%) and better visual outcomes than previously reported with Descemet stripping endothelial keratoplasty or an initial PK regraft.

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.

Indications and techniques employed for keratoplasty in the Eastern province of Saudi Arabia: 6 years of experience.

BACKGROUND AND OBJECTIVES: Keratoplasty services in Saudi Arabia have progressed steadily in the past few decades. We sought to identify the leading indications and types of keratoplasty performed in the Eastern Province of Saudi Arabia over a six-year period and to compare these indications with published data. DESIGN AND SETTING: This was a retrospective descriptive analysis of the records of patients who underwent keratoplasty at four ophthalmology centers in the Eastern Province between 2008 and 2013. PATIENTS AND METHODS: All keratoplasty procedures were included in the analysis. The primary surgical indication and type of surgery were identified for each case. RESULTS: Keratoplasties included 570 penetrating keratoplasty, 217 deep lamellar keratoplasty, 80 triple procedures, 24 descemet stripping automated endothelial keratoplasty and 12 Boston keratoprosthesis implantations. The mean age of all patients was 28.8 years (range 14-72 years), and 58.9% of the patient were males. The lead.ing indication for keratoplasty was keratoconus 53.10%, bullous keratopathy 13.80%, corneal scarring 10.7%, regrafts 9.1%, and stromal dystrophies 4.9%. CONCLUSIONS: In this study, the leading indications for keratoplasty were keratoconus, bullous keratopathy, corneal scarring, regrafts and stromal dystrophies. A significant increasing trend for descemet's stripping automated endothelial keratoplasty surgeries was observed in spite of the number of cases.

Keratoplasty in the United States: A 10-Year Review from 2005 through 2014.

PURPOSE: To report evolving indications and preferred techniques of corneal transplantation in the United States. DESIGN: Retrospective review. METHODS: Annual reports from the Eye Bank Association of America on corneal graft distribution in the United States from 2005 through 2014 were reviewed. MAIN OUTCOME MEASURES: Number and percentage of corneal grafts distributed for various types of keratoplasty and their surgical indications in the United States. RESULTS: The total number of corneal transplants increased from 44 277 in 2005 to 46 513 in 2014. In the past decade, penetrating keratoplasty dramatically decreased (from 95% to 42%) and largely has been replaced by various lamellar keratoplasty (LK) techniques (from 5% to 58%). Descemet stripping (automated) endothelial keratoplasty was the most common (50%) type of corneal transplantation performed in the United Stated in 2014. The volume of Descemet membrane endothelial keratoplasty (DMEK) has been doubling every year since 2011 and accounted for 11% of total endothelial keratoplasties in 2014. There was a significant shift in indication for corneal transplantation, with Fuchs' endothelial dystrophy (22%) being the most common, followed by corneal edema occurring after cataract surgery (12%) in 2014. Eye banks supplied precut corneal grafts for 68% of LK techniques in 2014. CONCLUSIONS: In the United States, there has been a major shift in preferred keratoplasty techniques over the past decade, with a wide adoption of new LK techniques.

Cornea preservation time study: methods and potential impact on the cornea donor pool in the United States.

PURPOSE: The aim of this study was to describe the aims, methods, donor and recipient cohort characteristics, and potential impact of the Cornea Preservation Time Study (CPTS). METHODS: The CPTS is a randomized clinical trial conducted at 40 clinical sites (70 surgeons) designed to assess the effect of donor cornea preservation time (PT) on graft survival 3 years after Descemet stripping automated endothelial keratoplasty (DSAEK). Eyes undergoing surgery for Fuchs endothelial corneal dystrophy or pseudophakic/aphakic corneal edema were randomized to receive donor corneas stored ≤7 days or 8 to 14 days. Donor and patient characteristics, tissue preparation and surgical parameters, recipient and donor corneal stroma clarity, central corneal thickness, intraocular pressure, complications, and a reading center-determined central endothelial cell density were collected. Surveys were conducted to evaluate pre-CPTS PT practices. RESULTS: The 1330 CPTS donors were: 49% >60 years old, 27% diabetic, had a median eye bank-determined screening endothelial cell density of 2688 cells/mm, and 74% eye bank prepared for DSAEK. A total of 1090 recipients (1330 eyes including 240 bilateral cases) had: median age of 70 years, were 60% female, 90% white, 18% diabetic, 52% phakic, and 94% had Fuchs endothelial corneal dystrophy. Before the CPTS, 19 eye banks provided PT data on 20,852 corneas domestically placed for DSAEK in 2010 to 2011; 96% were preserved ≤7 days. Of 305 American Academy of Ophthalmology members responding to a pre-CPTS survey, 233 (76%) set their maximum PT preference at 8 days or less. CONCLUSIONS: The CPTS will increase understanding of factors related to DSAEK success and, if noninferiority of longer PT is shown, will have great potential to extend the available pool of endothelial keratoplasty donors.Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01537393.

Endothelial cell loss and complication rates with combined Descemets stripping endothelial keratoplasty and cataract surgery in a UK centre.

PURPOSE: To report 6-month, 1- and 2-year endothelial cell loss (ECL), intra- and postoperative complications in a large series of patients undergoing either Descemets stripping endothelial keratoplasty (DSEK) or a combined phacoemulsification and DSEK in a UK centre. PATIENTS AND METHODS: Patients undergoing DSEK with or without concurrent cataract surgery were included in this retrospective study. Surgeries were performed between January 2006 and May 2013. Main outcomes included intra- and postoperative complications and percentage ECL. RESULTS: DSEK was performed in 226 eyes (210 patients). Of these, 141 eyes (126 patients) underwent DSEK alone and 85 eyes (84 patients) underwent DSEK combined with cataract surgery. Excluding complex anterior segment pathology the mean percentage ECL at 6, 12 and 24 months was 40.5±13.4, 45.1±14.6 and 53.1±13.0 in the DSEK group and 40.7±15.4, 42.6±15.3 and 49.6±16.5 in patients undergoing the combined procedure, respectively. There was no significant difference in percentage ECL at 6 or 24 months between the two groups both in complex and routine cases. Intraoperative complications occurred in four patients undergoing DSEK and three undergoing combined procedure. Postoperative complication rates did not reach statistical significance between the groups. CONCLUSION: Mean ECL and complication rates were comparable at 6, 12 and 24 months in routine cases undergoing concurrent DSEK with cataract surgery and those undergoing DSEK. These data support the combined procedure in patients requiring both cataract surgery and endothelial keratoplasty. Further collaboration to report endothelial cell counts from other UK centres should be encouraged.

Prevention and treatment of corneal graft rejection: current practice patterns of the Cornea Society (2011).

PURPOSE: To analyze current practice patterns in the prevention and treatment of corneal graft rejection for both penetrating keratoplasty (PK) and endothelial keratoplasty (EK) and to compare these patterns with previously reported practices. METHODS: In 2011, an electronic survey was sent to 670 members of the Cornea Society worldwide addressing the routine postoperative management of corneal transplants at different time points, treatment of various manifestations of corneal graft rejection, and preferred surgical techniques. RESULTS: A total of 204 of 670 surveys (30%) were returned and evaluated. All respondents used topical corticosteroids for routine postoperative management and treatment of endothelial graft rejection. Prednisolone was the topical steroid of choice in all clinical scenarios, similar to previous surveys from 1989 to 2004. Use of subconjunctival and systemic steroids increased for many scenarios of probable and definite graft rejection. Routine use of prednisolone decreased by approximately 10% from previous surveys, whereas difluprednate was used in 13% of high-risk eyes during the first 6 months. Dexamethasone, fluorometholone, and loteprednol use remained stable. Adjunctive topical cyclosporine use increased significantly for PK and EK. EK was the preferred technique for endothelial dysfunction, whereas PK and deep anterior lamellar keratoplasty were both used for keratoconus and anterior scars. Most respondents (75%) felt that graft rejection occurs more frequently after PK than after EK. CONCLUSIONS: Prednisolone remains the treatment of choice for management and treatment of graft rejection; however, since the introduction of difluprednate, its use has declined slightly since the introduction of difluprednate. Despite perceived differences in rejection rates, there were no differences in prophylactic steroid treatment for PK and EK.

Risk factors for eye bank preparation failure of Descemet membrane endothelial keratoplasty tissue.

PURPOSE: To assess the results of a single eye bank preparing a high volume of Descemet membrane endothelial keratoplasty (DMEK) tissues using multiple technicians to provide an overview of the experience and to identify possible risk factors for DMEK preparation failure. DESIGN: Cross-sectional study. METHODS: setting: Lions VisionGift and Wilmer Eye Institute at Johns Hopkins Hospital. STUDY POPULATION: All 563 corneal tissues processed by technicians at Lions VisionGift for DMEK between October 2011 and May 2014 inclusive. OBSERVATION PROCEDURES: Tissues were divided into 2 groups: DMEK preparation success and DMEK preparation failure. MAIN OUTCOME MEASURES: We compared donor characteristics, including past medical history. RESULTS: The overall tissue preparation failure rate was 5.2%. Univariate analysis showed diabetes mellitus (P = .000028) and its duration (P = .023), hypertension (P = .021), and hyperlipidemia or obesity (P = .0004) were more common in the failure group. Multivariate analysis showed diabetes mellitus (P = .0001) and hyperlipidemia or obesity (P = .0142) were more common in the failure group. Elimination of tissues from donors either with diabetes or with hyperlipidemia or obesity reduced the failure rate from 5.2% to 2.2%. Trends toward lower failure rates occurring with increased technician experience also were found. CONCLUSIONS: Our work showed that tissues from donors with diabetes mellitus (especially with longer disease duration) and hyperlipidemia or obesity were associated with higher failure rates in DMEK preparation. Elimination of tissues from donors either with diabetes mellitus or with hyperlipidemia or obesity reduced the failure rate. In addition, our data may provide useful initial guidelines and benchmark values for eye banks seeking to establish and maintain DMEK programs.

Analysis of the changes in keratoplasty indications and preferred techniques.

BACKGROUND: Recently, novel techniques introduced to the field of corneal surgery, e.g. Descemet membrane endothelial keratoplasty (DMEK) and corneal crosslinking, extended the therapeutic options. Additionally contact lens fitting has developed new alternatives. We herein investigated, whether these techniques have affected volume and spectrum of indications of keratoplasties in both a center more specialized in treating Fuchs' dystrophy (center 1) and a second center that is more specialized in treating keratoconus (center 2). METHODS: We retrospectively reviewed the waiting lists for indication, transplantation technique and the patients' travel distances to the hospital at both centers. RESULTS: We reviewed a total of 3778 procedures. Fuchs' dystrophy increased at center 1 from 17% (42) to 44% (150) and from 13% (27) to 23% (62) at center 2. In center 1, DMEK increased from zero percent in 2010 to 51% in 2013. In center 2, DMEK was not performed until 2013. The percentage of patients with keratoconus slightly decreased from 15% (36) in 2009 vs. 12% (40) in 2013 in center 1. The respective percentages in center 2 were 28% (57) and 19% (51). In both centers, the patients' travel distances increased. CONCLUSIONS: The results from center 1 suggest that DMEK might increase the total number of keratoplasties. The increase in travel distance suggests that this cannot be fully attributed to recruiting the less advanced patients from the hospital proximity. The increase is rather due to more referrals from other regions. The decrease of keratoconus patients in both centers is surprising and may be attributed to optimized contact lens fitting or even to the effect corneal crosslinking procedure.