Descemet Stripping Automated Endothelial Keratoplasty Research Articles

Comparison of Artificial Anterior Chamber Internal Pressures and Cutting Systems for Descemet's Stripping Automated Endothelial Keratoplasty.

PurposeTo optimize methods of preparing donor cornea tissue for Descemet's stripping automated endothelial keratoplasty (DSAEK), we compared five experimental conditions with different internal pressures and cutting systems.MethodsThe artificial anterior chamber internal pressure (IP) was set at 100 or 200 mm Hg. The microkeratome cut was performed with or without an artificial chamber pressurizer (ACP), using a CBm turbine (CBm) or one use-plus automated (OUP-A). Thirty human research corneas were divided into five groups, and compared after the cut with donor tissue quality parameters, including cutting depth, graft uniformity, cell evaluation, and smoothness of the stromal surface.ResultsThe smallest variation in mean cut depth was observed in the condition, which had IP of 200 mm Hg used ACP and OUP-A. In experimental groups cut using CBm, significantly more consistent thicknesses were made at an IP of 200 than 100 mm Hg. There were no statistically significant differences among the groups in either endothelial cell density or cell viable assay results after cuts. Using an IP of 200 mm Hg with ACP and CBm produced the roughest stromal surface, and the roughness grading scores showed a positive correlation with the percentage of cut depth.ConclusionsAn IP of 200 mm Hg was the best setting for DSAEK grafts with high predictability of cut depth and uniformity of graft thickness without endothelial cell damage.Translational RelevanceFor successful DSAEK, it is recommended that a set internal pressure of 200 mm Hg be used during microkeratome cutting for donor tissue preparation.

Risk Factors for Endothelial Decompensation after Penetrating Keratoplasty and Its Novel Therapeutic Strategies.

Purpose To review the risk factors and pathogenesis of endothelial decompensation after penetrating keratoplasty (PKP) and its novel therapeutic strategies. Methods Literature review. Results As the major cause of graft failure in PKP, endothelial decompensation of corneal allograft is considered an irreversible decrease in endothelial cell density and endothelial dysfunction. Various risk factors, including donor status and operative and recipient factors, have been found to be associated with this pathological process. Operative factors like graft size and recipient factors such as indications, glaucoma, or glaucoma surgery history are highly associated with the occurrence of endothelial decompensation, while others are still under investigation. Although the mechanism of these risk factors remains unclear, pathogenesis can be summarized as an acute and chronic loss of endothelium, and cell exchange between donor and recipient is at the core of chronic cell loss. Endothelial keratoplasty has been a useful alternative to repeat standard PKP in eyes with failed grafts. Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet's membrane endothelial keratoplasty (DMEK) following failed PKP provide more rapid visual recovery and achieve better rates of graft survival than those of a second PKP. Conclusions Any direct or indirect damage to the endothelium could cause the loss, morphological changes, and dysfunction of endothelial cells. Graft size, indications, and recipient glaucoma or glaucoma surgery history are risk factors for endothelial decompensation. DSAEK and DMEK are novel therapeutic strategies for failed PKP grafts and have potential superiorities compared with repeat PKP.

Donor, Recipient, and Operative Factors Associated With Increased Endothelial Cell Loss in the Cornea Preservation Time Study

Determining factors associated with endothelial cell loss after Descemet stripping automated endothelial keratoplasty (DSAEK) could improve long-term graft survival. To evaluate the associations of donor, recipient, and operative factors with endothelial cell density (ECD) 3 years after DSAEK in the Cornea Preservation Time Study. This cohort study was a secondary analysis of data collected in a multicenter, double-masked, randomized clinical trial. Forty US clinical sites with 70 surgeons participated, with donor corneas provided by 23 US eye banks. Individuals undergoing DSAEK for Fuchs dystrophy or pseudophakic/aphakic corneal edema were included. The DSAEK procedure, with random assignment of a donor cornea with a preservation time of 0 to 7 days or 8 to 14 days. Endothelial cell density at 3 years as determined by a reading center from eye bank and clinical specular or confocal central endothelial images. The study included 1090 participants (median age, 70 years) with 1330 affected eyes (240 bilateral cases [22.0%]), who underwent DSAEK for Fuchs dystrophy (1255 eyes [94.4%]) or pseudophakic/aphakic corneal edema (PACE) (75 eyes [5.6%]). Of these, 801 eyes (60.2%) belonged to women and 1207 (90.8%) to white individuals. A total of 749 participants (913 eyes; 164 [21.9%] bilateral cases) had functioning grafts with acceptable endothelial images preoperatively and at 3 years postoperatively and were included in this analysis. Factors associated with a lower ECD at 3 years (estimated effect with 99% CI) in the final multivariable model included donors with diabetes (-103 [-196 to -9] cells/mm2), lower screening ECD (-234 [-331 to -137] per 500 cells/mm2), recipient diagnosis of PACE (-257 [-483 to -31] in cells/mm2), and operative complications (-324 [-516 to -133] in cells/mm2). Endothelial cell loss (ECL) from a preoperative measurement to a 3-year postoperative measurement was 47% (99% CI, 42%-52%) for participants receiving tissue from donors with diabetes vs 43% (99% CI, 39%-48%) without diabetes; it was 53% (99% CI, 44%-62%) for participants diagnosed with PACE vs 44% (99% CI, 39%-49%) for those diagnosed with Fuchs dystrophy, and 55% (99% CI, 48%-63%) in participants who experienced operative complications vs 44% (99% CI, 39%-48%) in those who did not. No other donor, recipient, or operative factors were significantly associated with 3-year ECD. Donor diabetes, lower screening ECD, a PACE diagnosis in the recipient, and operative complications were associated with lower ECD at 3 years after DSAEK surgery and may be associated with long-term graft success. While causation cannot be inferred, further studies on the association of donor diabetes and PACE in recipients with lower 3-year ECD warrant further study.

Retrospective Single-Center Registry Study on Graft Thickness 1 Year After Descemet Stripping Automated Endothelial Keratoplasty.

To compare the graft thickness of eye bank precut grafts with graft thickness measured 1 year after Descemet stripping automated endothelial keratoplasty (DSAEK) and to correlate the graft thickness of eye bank precut grafts with best spectacle-corrected visual acuity (BSCVA) and endothelial cell density (ECD) 1 year after DSAEK. This was a retrospective registry study of 183 eyes of 179 DSAEK patients. Grafts were cut in the eye bank after 1 day in dextran-containing medium, and thickness was measured by optical coherence tomography immediately after precutting. Examinations 1 year after DSAEK included optical coherence tomography for graft thickness, BSCVA, and specular microscopy. Patients were divided into 2 groups based on the median graft thickness. The correlations between original graft thickness and graft thickness measured 1 year later, BSCVA, and ECD were analyzed by linear regression analyses. Graft thickness decreased from 116 ± 36.8 μm before to 100 ± 36.8 μm 1 year after DSAEK (R =0.901, P <0.0001). Mean BSCVA 1 year after DSAEK was 0.24 logMAR in eyes without ocular comorbidity. BSCVA was 0.25 ± 0.16 (0.21-0.28) and 0.20 ± 0.11 (0.18-0.23) in eyes with a graft thickness above or below 111 μm, respectively (P = 0.04). ECD loss 1 year after surgery did not correlate with graft thickness (R = 0.0006, P <0.875). Graft thickness measured immediately after precutting correlates strongly with graft thickness measured 1 year after DSAEK. This study suggests that ultrathin grafts provide better visual acuity 1 year after DSAEK than regular grafts.

Factors Associated With Graft Rejection in the Cornea Preservation Time Study

To identify factors related to graft rejection following Descemet stripping automated endothelial keratoplasty (DSAEK) in the Cornea Preservation Time Study (CPTS). Cohort study within a multicenter randomized clinical trial. A total of 1330 eyes of 1090 subjects undergoing DSAEK were randomized to receive a donor cornea with preservation time (PT) of 0-7days (n=675) or 8-14days (n= 655) and followed for 3 years. Central endothelial cell density (ECD) was determined by a central image analysis reading center. Multivariable Cox models adjusted for PT, recipient diagnosis, and surgeon effect were used to identify factors associated with rejection. Cumulative probability of definite graft rejection was 3.6% (99% confidence interval 2.5%-5.3%). Younger recipient age was associated with graft rejection (P < .001; hazard ratio: 0.53 [0.33, 0.83] per decade). PT, donor-recipient sex mismatch, recipient diagnosis, recipient race, graft size, discontinuation of topical corticosteroids and immune-modulators, prior immunizations within 3months, and prior glaucoma surgery were not associated with rejection (P > .01). Among clear grafts with an ECD measurement at baseline and 3 years (n= 913), endothelial cell loss (ECL) was greater in eyes that experienced a rejection episode (n= 27) than in those that did not (n= 886) (48% vs 38%, P= .03). Twelve of 44 eyes (27%) with definite graft rejection subsequently failed, comprising 15% of the 79 failures in the CPTS. Graft rejection is uncommon after DSAEK and more likely with younger age, in a study cohort mostly > 50 years old. Rejection increases ECL, but it is not a leading cause of DSAEK failure.

Automated 2D-3D quantitative analysis of corneal graft detachment post DSAEK based on AS-OCT images

Background and Objective: In current ophthalmological practices, assessment of graft condition post Descemet’s stripping automated endothelial keratoplasty (DSAEK) is performed qualitatively using few (four) anterior-segment optical coherence tomography (AS-OCT) radial B-scans. From those scans, clinicians need to mentally synthesize the graft in 3D, and estimate its overall condition. In contrast, quantitative representation of 360° thickness profile would facilitate better visualization of graft condition, and hence medical decision making. Consequently, clinicians seek to quantify potential detachments in 3D from the aforementioned sparse B-scans. Against this backdrop, aiming to assist doctors in making an accurate postoperative assessment, we attempted at 3D visualization and quantification of donor lenticule separation (DLS) using only four AS-OCT radial B-scans.Methods: We developed an automated methodology to model and quantify DLS in 3D using only four AS-OCT B-scans. Firstly, we demonstrated that detachment can be viewed as a tubular vessel-like structure and hence can be detected using Hessian matrix analysis. Secondly, a two-stage interpolation was employed for determining the 3D profile of the detachment. Finally, various clinically significant parameters including type of separation (communicative and non-communicative), volume and 360° thickness profile of the detachment, thickness (central and peripheral) of the recipient cornea and donor graft were also obtained. Accuracy of the proposed algorithm was substantiated via thorough statistical analysis, specifically, vis-á-vis intra- and inter-observer repeatability using Dice coefficient (DC).Results: On twenty seven eyes of 27 patients (male and female), four radial OCT B-scans with 45° angular separation taken per eye, proposed algorithm found that donor graft detached completely in 3 eyes and detached one side (communicative) in remaining 24 eyes which is in agreement with expert’s opinion. Quantitatively, proposed algorithm achieves a mean DC of 81.35% with manual reference which is close to the corresponding inter-observer repeatability value of 86.77%. Volume estimation of the detachment indicates that 11 eyes had 0–25%, 9 had 25–50%, 5 had 50–75% and 2 had 75–100% detachment.Conclusions: Accuracy of the proposed methodology was corroborated vis-à-vis observer delineation. This model of image analysis may aid in prognostication of graft outcome in patients with graft detachment after DSAEK.

Cost-Effectiveness Analysis of Descemet’s Membrane Endothelial Keratoplasty Versus Descemet’s Stripping Endothelial Keratoplasty in the United States

To determine the cost-effectiveness of Descemet's membrane endothelial keratoplasty (DMEK) compared with Descemet's stripping automated endothelial keratoplasty (DSAEK) in the United States. Cost-effectiveness analysis in a surgical center in the United States. Binocular adult patient undergoing endothelial keratoplasty. A base case of a 70-year-old man undergoing his first endothelial keratoplasty for bilateral Fuchs endothelial dystrophy. The cost-effectiveness of DMEK was compared with DSAEK over a 15-year time horizon. The incidences and costs of complications were derived from PubMed English literature searches, Medicare reimbursements, and average wholesale prices. All costs were discounted 3% per annum and adjusted for inflation to 2018 U.S. dollars. Uncertainty was evaluated using deterministic and probabilistic sensitivity analyses. Incremental cost-effectiveness ratios and incremental cost-utility ratios, measured in cost per quality-adjusted life-years (QALYs). Performing a DMEK instead of a DSAEK generated an extra 0.4 QALYs over a 15-year period. From a societal and third-party payer perspective, DMEK was cost-saving when compared with DSAEK in improving visual acuity in the base case. Probabilistic sensitivity analyses with variations in the costs and rebubble rates revealed that DMEK was cost-saving compared with DSAEK in 38% of iterations and was within a societal willingness-to-pay threshold of $50 000 in 98% of models. From the societal and third-party payer perspectives in the United States, DMEK generated greater utilities and was less costly than DSAEK. Therefore, DMEK was the dominant procedure and was cost-saving with respect to DSAEK. The economic model was robust based on sensitivity analyses.

Topical non-steroidal anti-inflammatory drugs for the treatment of cystoid macular edema post Descemet's stripping automated endothelial keratoplasty.

To investigate the effectiveness of topical non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of cystoid macular edema (CME) post Descemet's stripping automated endothelial keratoplasty (DSAEK). Retrospective observational study METHODS: In this study of 334 patients who underwent DSAEK at the Baptist Eye Institute, Kyoto, Japan between July 2011 and December 2015, 18 patients with postoperative CME (determined by optical coherence tomography) treated with topical NSAIDs after the onset of CME were included. At CME onset, 17 of the 18 patients were treated with bromfenac eye drops and 1 was treated with nepafenac eye drops. Post initiation of treatment with topical NSAIDs, CME in 17 (94.4%) of the 18 patients improved at 1month and all cases completely recovered within 3months. At 12-months post initiation of treatment, 61.1% (n = 11) of patients achieved a visual acuity (VA) of 20/40 or better, and there was no significant difference of VA between the patients with or without an episode of postoperative CME (P = 0.55). The administration of topical NSAID eye drops was found to be effective in treating patients with CME post DSAEK.

Donor, Recipient, and Operative Factors Associated with Graft Success in the Cornea Preservation Time Study

To associate donor, recipient, and operative factors with graft success 3 years after Descemet stripping automated endothelial keratoplasty (DSAEK) in the Cornea Preservation Time Study (CPTS). Cohort study within a multicenter, double-masked, randomized clinical trial. One thousand ninety individuals (1330 study eyes) with a median age of 70 years undergoing DSAEK for Fuchs endothelial corneal dystrophy (94% of eyes) or pseudophakic or aphakic corneal edema (PACE; 6% of eyes). Eyes undergoing DSAEK were randomized to receive a donor cornea with preservation time (PT) of 0 to 7 days (n= 675) or 8 to 14 days (n= 655). Donor, recipient, and operative parameters were recorded prospectively. Graft failure was defined as regraft for any reason, a graft that failed to clear by 8 weeks after surgery, or an initially clear graft that became and remained cloudy for 90 days. Failure in the first 8 weeks was classified further as primary donor failure or early failure, in the absence or presence of operative complications, respectively. Proportional hazards and logistic regression models were used to estimate risk ratios (RR) and 99% confidence intervals (CIs) for graft failure. Graft success at 3 years. One thousand two hundred fifty-one of 1330 grafts (94%) remained clear at 3 years and were considered successful. After adjusting for PT, tissue from donors with diabetes (RR, 2.35; 99% CI, 1.03-5.33) and operative complications (RR, 4.21; 99% CI, 1.42-12.47) were associated with increased risk for primary or early failure. Preoperative diagnosis of PACE (RR, 3.59; 99% CI, 1.05-12.24) was associated with increased risk for late failure by 3 years after surgery compared with Fuchs dystrophy. Graft success showed little variation among other factors evaluated, including donor age (RR, 1.19 per decade; 99% CI, 0.91-1.56 per decade), preoperative donor endothelial cell density (RR, 1.10 per 500 cells; 99% CI, 0.74-1.63 per 500 cells), graft diameter (RR, 1.22 per 1 mm; 99% CI, 0.39-3.76 per 1 mm), and injector use for graft insertion (RR, 0.92; 99% CI, 0.40-2.10). Descemet stripping automated endothelial keratoplasty success in the early and entire postoperative period is more likely when the donor did not have diabetes and was without operative complications and in the long-term postoperative period in recipients with Fuchs dystrophy compared with those with PACE. Mechanisms whereby diabetic donors and PACE recipients reduce the rate of graft success after DSAEK warrant further study.

A 10-year review of underlying diseases for endothelial keratoplasty (DSAEK/DMEK) in a tertiary referral hospital in Japan.

PurposeTo report a 10-year review of endothelial keratoplasty (EK) procedures, Descemet’s stripping automated endothelial keratoplasty (DSAEK) and Descemet’s membrane endothelial keratoplasty (DMEK), and underlying diseases at a tertiary referral hospital in Japan.Study designA single-center, retrospective case series.MethodsWe retrospectively reviewed all medical records of bullous keratopathy (BK) surgically treated by EK (DSAEK/DMEK) at Kanazawa University Hospital from January 2007 to December 2016. Changes or modifications to the annual number of EK procedures and underlying diseases were analyzed.ResultsDuring this period, 320 EK procedures (DSAEK: 288 cases, DMEK: 32 cases) were performed on 250 patients. Total annual EKs gradually increased from 19 to 45 cases between 2007 and 2016. The annual number of DSAEKs was stable, although the proportion of DSAEKs to other procedures decreased significantly as re-DSAEKs and DMEKs increased. BK after argon laser iridotomy (ALI) was the leading cause in 2007, followed by Fuchs’ endothelial dystrophy (FED) and failed penetrating keratoplasty. In 2016, BK after trabeculectomy (TLE) was most prevalent, followed by failed DSAEK, failed penetrating keratoplasty, and pseudophakic BK. The decreased ALI and FED, and increased BK after TLE and failed DSAEK were statistically significant.ConclusionThe distribution of EK procedures (DSAEK/DMEK) and underlying diseases changed over 10 years at a tertiary referral hospital in Japan. The proportion of re-DSAEK and DMEK increased among all EK procedures. Most significantly, among the underlying diseases, decreased ALI and FED and increased TLE and failed DSAEK were observed. Extended multicenter analysis may further elucidate the changes in EK procedures and the causes of BK in Japan.

Tectonic epikeratoplasty with ethanol-stored donor corneas.

To evaluate the efficacy and outcomes of tectonic epikeratoplasty with use of ethanol-preserved corneal grafts for the management of perforated corneal melts. The present retrospective case series includes 10 eyes which underwent tectonic epikeratoplasty for perforated corneal melts. The stromal remainders of Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK) graft preparation were stored in 95% ethanol and used as emergency tectonic grafts for restoring globe integrity after sterile and infectious perforated corneal melts. In 6 cases with subtotal corneal melt, DMEK remainders (endothelium-denuded corneoscleral buttons) were used for 'limbus to limbus' tectonic epikeratoplasty and in 4 cases DSAEK remainders (anterior stroma) were used to seal focal perforated melts. Graft storage time was 5.1 ± 4.9 (ranging from 0.5 to 17) months. The surgeries were successful in all cases with restitution of the globe integrity. During the postoperative course 4 cases developed a graft melt (corneoscleral button for limbus to limbus tectonic epikeratoplasty, n = 3; lamellar patch, n = 1) within 2-6months after the initial procedure. Three patients underwent successful repeat tectonic epikeratoplasty. In the fourth case of graft melt the globe was enucleated due to underlying expulsive haemorrhage and severe pain. The short-term results of the present case series suggest that the use of ethanol-stored stromal remainder of donor corneas after endothelial keratoplasty is an efficient temporary measure for tectonic restoration of perforated corneas.

Precut Post–Laser In Situ Keratomileusis / Photorefractive Keratectomy Donor Corneas for Use in Endothelial Keratoplasty: Potential Impact of Postcut Morphology on Visual Outcomes

To evaluate the accuracy, complication rates, cut quality, and degree of induced hyperopic shift of eye bank-prepared post-laser insitu keratomileusis (LASIK)/photorefractive keratectomy (PRK) donor corneas compared to those of non-post-LASIK/PRK donor corneas. The cut accuracy and failure rates of all post-LASIK/PRK donor cornea tissue processed for use in Descemet stripping automated endothelial keratoplasty (DSAEK) from January 2012 through December 2016 were compared to control cornea donor tissue. Corneas were analyzed for regularity and morphology of cut using anterior segment optical coherence tomography images. Using a mathematical model, the hyperopic shifts induced by post-LASIK/PRK donor lenticules were compared to the control corneas. During the study period, 733 post-LASIK/PRK and 10 437 non-post-LASIK/PRK donor corneas were processed for DSAEK. Cut accuracy and quality were similar (P > .05), but there was an increased tissue wastage rate of 5.0% compared to 2.2% (P < .000001). For tissue < 100μm in central thickness (P= .0001), and for tissue between 100 and 150μm in central thickness (P= .0023), the difference between central and peripheral thickness when comparing the post-LASIK/PRK and control corneas was statistically significant. These differences resulted in a 1.96 diopter (D), 1.60 D, and 2.35 D hyperopic shift when using donor corneas 100μm, 125μm, and 150μm thick, respectively, from post-LASIK/PRK donors compared to 1.11 D, 0.38 D, and 1.96 D from control donors. Eye bank technicians and surgeons should be aware of the increased risk of tissue wastage when cutting post-LASIK/PRK corneas compared to non-post-LASIK/PRK donors. Surgeons should also be aware of the theoretical increase in hyperopic shift when using post-LASIK/PRK donor corneas compared to non-post-LASIK/PRK donors when cut to less than 150μm. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Outcome of Human Donor Corneas Stored for More Than 4 Weeks.

Organ culture is the most common method for preservation of human donor corneas within Europe, and the maximum accepted storage period is typically set to 4 weeks. However, little is known about the fate of prolonged (4+ wks) organ culture storage of donor corneas. The aim of this study was to evaluate the clinical outcomes of corneal grafts preserved from 4 to 7 weeks compared with corneal grafts preserved up to 4 weeks in organ culture medium. A registry study was performed, identifying 1252 corneal transplantations [Descemet stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PKP)] between February 2008 and November 2015 at Aarhus University Hospital, Denmark. Data were extracted from The Danish Cornea Bank Registry and The Swedish Cornea Registry, which also includes Danish patients. The outcomes evaluated, 2 years after transplantation, were graft function, rebubbling rates in DSAEK surgeries, rejection rates, and endothelial cell density (ECD). A total of 808 donor corneas were stored for ≤29 days, with a mean preservation time being 20 ± 6 days (mean ± SD, range: 6-29 days). A total of 444 donor corneas were stored for >29 days, with a mean preservation time being 38 ± 7 days (mean ± SD, range: 30-72 days). In both DSAEK (n = 835) and PKP (n = 417), no statistically significant difference was observed in the frequency of graft failure (DSAEK, P = 0.9 and PKP, P = 0.74), rebubbling rates (DSAEK P = 0.07), rejection rates (DSAEK, P = 0.08 and PKP, P = 0.95), or ECD (DSAEK, P = 0.56 and PKP, P = 0.44) between donor corneas cultured for ≤29 days and donor corneas cultured for >29 days. Corneas stored in organ culture for more than 4 weeks are equally suitable for DSAEK and PKP transplantation as corneas stored in organ culture for up to 4 weeks.

Immune Cells on the Donor Corneal Endothelium After Corneal Transplantation.

The aim of this study was to investigate the existence of presumed immune cells observed by contact specular microscopy in patients who underwent penetrating keratoplasty (PK) and Descemet stripping automated endothelial keratoplasty (DSAEK). This cross-sectional study was conducted on consecutive patients who underwent follow-up visits between January and March 2015 for previously performed PK or DSAEK. Presumed immune cell-suspected "cell-like white dots" were evaluated by scanning slit contact specular microscopy. The association between the grading of presumed immune cells with clinical parameters, such as corneal endothelial cell density, time after surgery, and the titer of steroid administration, was also investigated. A total of 54 eyes of 54 patients who underwent PK (32 eyes/32 patients) and DSAEK (22 eyes/22 patients) were evaluated, and suspected immune cells were observed in all patients. In the PK and DSAEK groups, the number of patients in the presumed immune cell grades 1, 2, 3, and 4 were 19, 10, 2, and 1 and 10, 8, 2, and 2, respectively (P = 0.663). No statistically significant association was found between the immune cell grades and the clinical parameters. Immune cells were observed on the corneal endothelial grafts in all 54 patients who underwent PK or DSAEK. Although the number of immune cells varied between patients and showed no correlation with clinical parameters, it would be beneficial to conduct a future prospective study to analyze the effect of immune cells on postoperative corneal endothelial cell loss.

Descemet's membrane endothelial keratoplasty (DMEK) versus Descemet's stripping automated endothelial keratoplasty (DSAEK) for corneal endothelial failure.

Corneal endothelial transplantation has become the gold standard for the treatment of corneal endothelial dysfunctions, replacing full thickness transplantation, known as penetrating keratoplasty. Corneal endothelial transplantation has been described using two different techniques: Descemet's membrane endothelial keratoplasty (DMEK) and Descemet's stripping automated endothelial keratoplasty (DSAEK). Both are still performed worldwide. To compare the effectiveness and safety of Descemet's membrane endothelial keratoplasty (DMEK) versus Descemet's stripping automated endothelial keratoplasty (DSAEK) for the treatment of corneal endothelial failure in people with Fuch's endothelial dystropy (FED) and pseudophakic bullous keratopathy (PBK). We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 7); MEDLINE Ovid; Embase Ovid; LILACS BIREME; the ISRCTN registry; ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). The date of the search was 11 August 2017. We included randomised controlled trials (RCTs) and non-randomised paired, contralateral-eye studies in any setting where DMEK was compared with DSAEK to treat people with corneal endothelial failure. Two review authors independently screened the search results, assessed trial quality and extracted data using the standard methodological procedures expected by Cochrane. Our primary outcome was best corrected visual acuity (BCVA) measured in logarithm of the Minimum Angle of Resolution (logMAR). Secondary outcomes were endothelial cell count, graft rejection, primary graft failure and graft dislocation. We graded the risk of bias of non-randomised studies (NRSs) using ROBINS-I. We did not identify any RCTs but found four non-randomised studies (NRSs) including 72 participants (144 eyes), who had received DSAEK in the first eye followed by DMEK in the fellow eye. All the studies included adult participants where there was evidence of FED and endothelial failure requiring a corneal transplant for the treatment of visual impairment. We did not find any studies that included PBK. The trials were published between 2011 and 2015, and we assessed them as high risk of bias due to potential unknown confounding factors since DSAEK preceded DMEK in all participants. Two studies reported results at 12 months, one at 6 months, and one between 6 and 24 months. At one year, using DMEK in cases of endothelial failure may result in better BCVA compared with DSAEK (mean difference (MD) -0.14, 95% confidence interval (CI) -0.18 to -0.10 logMAR, 4 studies, 140 eyes, low-certainty evidence). None of the participants had severe visual loss (BCVA of 1.0 logMAR or more; very low-certainty evidence). Regarding endothelial cell count data (4 studies, 134 eyes) it is hard to draw any conclusions since two studies suggested no difference and the other two reported that DMEK provides a higher cell density at one year (very low-certainty evidence). No primary graft failure and only one graft rejection were recorded over four studies (144 eyes) (very low-certainty evidence). The most common complications reported were graft dislocations, which were recorded in one or two out of 100 participants with DSAEK but were more common using DMEK, although this difference could not be precisely estimated (risk ratio (RR) 5.40, 95% CI 1.51 to 19.3; 4 studies, 144 eyes, very low-certainty evidence). This review included studies conducted on people with corneal endothelium failure due to FED for whom both DMEK and DSAEK can be considered, and found low-certainty evidence that DMEK provides some advantage in terms of final BCVA, at the cost of more graft dislocations needing 're-bubbling' (very low-certainty of evidence).

Porcine endothelial grafts could survive for a long term without using systemic immunosuppressors: An investigation of feasibility and efficacy of xeno-Descemet's stripping automated endothelial keratoplasty from WZS-pig to rhesus monkey.

In current non-human primate models, full-thickness porcine grafts could not achieve long-term survival without using potent systemic immunosuppressors. Moreover, the thickness disparity in xeno-PKP proved to be hard to manipulate and may cause several complications which also could prevent the grafts from long survival. Considering the advantages of Descemet's stripping automated endothelial keratoplasty (DSAEK) derived from its ultrathin graft and lower rejection rate, we hypothesize xeno-DSAEK may overcome these imperfections in xeno-PKP. The aim of this study was to explore the feasibility and efficacy of xeno-DSAEK and to investigate the possibility of long-term survival of porcine DSAEK grafts only using local immunosuppressors. Nine rhesus monkeys were divided into two groups. In the DSAEK group (n=7), Descemet's membrane stripping was performed to establish the bullous keratopathy model followed by the endothelial graft transplant. In the control group (n=2), only DM stripping was performed. Betamethasone 3.5mg was injected subconjunctivally every 10 days for a total of 10 times in the DSAEK group. After the surgery, all grafts were evaluated by slit lamp microscopy for at least 6months. In addition, anterior segment optical coherence tomography (AS-OCT) and confocal laser microscopy (CLM) were hired to evaluate the graft attachment and survival. To investigate the rejection mechanism for xeno-DSAEK, pathological and immunity examinations, including immunohistochemistry, immunofluorescence, T-cell subgroups, cytokine concentration, and anti-GAL antibodies, were performed and compared between the survived and rejected grafts. In the control group, the corneal opacity gradually increased with the development of corneal swelling and neovascularization. In the DSAEK group, five recipients (n=5/7) re-established their transparencies within 30days after xeno-DSAEK, and four grafts survived >180days (>180, >180, >298, >270) only by injecting betamethasone subconjunctivally, whereas two grafts (n=2/7) rejected in 30days. The AS-OCT and CLM showed the survived grafts attached firmly to the host beds, and the endothelial cell density was adequate (>2000cells/mm2 ) to maintain the graft function at post-operative month 6. The immunohistochemistry showed predominantly T cells (CD4+ and CD8+) and macrophages infiltrated in the rejected grafts, although a few B cells (CD20+) were also observed. Moreover, immunofluorescence demonstrated donor-specific antibody (IgG) and complement (C3c) were also involved in the immune rejection. However, T-cell subgroups and cytokine concentrations (except for IL-6) showed no significant differences between the rejected and survived grafts. Xeno-DSAEK is feasible and effective, and the technique may reduce the complications common to xeno-PKP. More importantly, the porcine DSAEK grafts could survive for a long term without using systemic immunosuppressors and exhibit promising future for clinical practice.

Anterior Segment Optical Coherence Tomography of Post-Descemet Stripping Automated Endothelial Keratoplasty Eyes to Evaluate Graft Morphology and Its Association With Visual Outcome.

To evaluate the relationship between graft thickness/regularity and visual outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK). Records of post-DSAEK patients who were examined by anterior segment optical coherence tomography at "Villa Igea" Private Hospital (Forlì, Italy) since April 2015 were reviewed. Pachymetric and elevation maps of both host cornea and graft were analyzed. Graft regularity was determined based on the root mean square error (RMSE) of the graft pachymetric measurements taken 3 and 6 mm from the center and the RMSE of the corneal elevation measurements at its posterior and interface surfaces. These parameters were correlated with best-spectacle-corrected visual acuity (BSCVA) (expressed in logarithm of the minimum angle of resolution) and compared between eyes with central graft thickness (CGT) ≥100 μm (group 1) and eyes with CGT <100 μm (group 2). Eighty-nine post-DSAEK eyes of 89 patients with Fuchs endothelial dystrophy or bullous keratopathy and no significant comorbidities were included. There were 40 eyes (CGT = 138.2 ± 31.7 μm) in group 1 and 49 eyes (CGT = 73.3 ± 15.5 μm) in group 2. The RMSEs of graft pachymetry and the RMSEs of the interface and posterior surface elevation maps at 3 and 6 mm differed significantly between both groups (P < 0.05). When only eyes with Fuchs endothelial dystrophy (n = 54) were considered in both groups, there was a statistically significant correlation (r = 0.44; P = 0.001) between BSCVA and CGT. DSAEK grafts thinner than 100 μm are more regular than thicker ones. In eyes with Fuchs endothelial dystrophy that are otherwise healthy, thinner grafts yield significantly better BSCVA.

New trends in corneal transplants at the University of Toronto

ObjectiveTo assess trends in surgical procedures and indications for all corneal transplants performed at the University of Toronto. DesignRetrospective cross-sectional study. ParticipantsOne thousand one hundred and four consecutive corneal transplants performed at the Kensington Eye Institute (KEI). MethodsDemographic, clinical, and pathological data retrieved from the Ophthalmic Pathology Laboratory on all corneal transplants performed at the KEI from January 2014 to December 2016. ResultsOver 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. ConclusionsPartial-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.

Long-term follow-up of deep anterior lamellar keratoplasty after Descemet stripping automated endothelial keratoplasty.

To describe the long-term outcomes of deep anterior lamellar keratoplasty (DALK) performed after Descemet stripping automated endothelial keratoplasty (DSAEK) in cases of infection and residual stromal opacity. Ten eyes of nine consecutive patients undergoing DALK after DSAEK at a single tertiary referral center (SNEC) from 2011 to 2016 were analyzed for best spectacle-corrected visual acuity (BSCVA), refraction, spherical equivalent (SE) and cylinder, as well as graft diameters, survival, and complications. The mean pre-DSAEK BSCVA was 1.73 ± 0.76 LogMAR. At a mean follow-up of 9.8 ± 7.1months, visual acuity had improved significantly (p = 0.028) to 1.09 ± 0.55 LogMAR after DSAEK. DALK was performed at 10.3 ± 7.2months after DSAEK because of residual stromal scarring in nine and a corneal infection in one case. At the last follow-up visit (19.4 ± 13.9months) after DALK, BSCVA had improved to 0.38 ± 0.6 LogMAR, significantly better than after DSAEK alone (p = 0.015) and before DSAEK (p = 0.018). Spherical equivalent (- 4.8 ± 3.5 D) and cylinder (- 2.5 ± 2.0 D) did not show significant changes compared to after DSAEK (SE p = 0.17; cylinder p = 0.19) or 3months after DALK (SE p = 0.17; cylinder p = 0.46). One endothelial graft failed 3months after DALK. Kaplan-Meier estimated average survival for all cases was 45.3 (95% CI 36.6-54.0) months. The cumulative survival probability for the entire cohort was 90% at 1, 2, and 4years of follow-up. DALK surgery after DSAEK can improve vision in cases of residual host scarring and treat host corneal infection, while avoiding open-sky surgery and sparing a healthy endothelial graft.

Outcomes of the first 250 eyes of Descemet membrane endothelial keratoplasty: Canadian centre experience

ObjectiveTo report and analyze the clinical outcomes of the first 250 cases of Descemet membrane endothelial keratoplasty (DMEK). MethodsA retrospective case series was conducted on the first 250 DMEK cases. The cohort included eyes with previous trabeculectomy, pre-existing glaucoma drainage device, and previous vitrectomy. Outcomes measures were best spectacle-corrected visual acuity (BSCVA), endothelial cell loss (ECL), episodes of rejection, detachment, rebubbling rate, and the need for repeat transplantation. Subgroup analysis was performed between eyes with different etiologies and between different DMEK injectors. ResultsThe median BSCVA increased from 0.6 [0.4, 1.3] logMAR (Snellen equivalent, 20/80) before surgery to 0.3 [0.2, 0.5] logMAR (Snellen equivalent, 20/40) 6 months after DMEK (p < 0.001). The median ECL at 6 months after surgery was 26.1%. Thirty-nine eyes (15.6%) had graft detachment involving more than one third of the graft and required rebubbling. Two eyes (0.8%) had a graft rejection episode. Fifteen eyes (6%) had graft failure for which 13 eyes (5.2%) had repeat DMEK, 1 eye (0.4%) had repeat Descemet stripping automated endothelial keratoplasty (DSAEK), and 1 eye (0.4%) had repeat penetrating keratoplasty (PKP). Fuchs’ patients and failed PKP patients gained more vision at 6 months post-DMEK compared with other etiologies (pseudophakic bullous keratopathy and failed DSAEK) (p < 0.001). ConclusionsOur data suggest that DMEK is a safe and effective procedure with excellent visual outcomes. DMEK can be done in association with other co-morbidities such as post-trabeculectomy, glaucoma drainage device, previous vitrectomy, and failed corneal grafts with a good prognosis.