[Pathogenesis of Fuchs endothelial corneal dystrophy, the fibrillar layer and individualized treatment]. / Pathogenese der Fuchs-Endotheldystrophie, die fibrilläre Schicht und individualisierte Therapie.

Fuchs endothelial corneal dystrophy (FECD) is a genetic and age-associated corneal disease characterized by an accelerated loss of corneal endothelial cells and an increased subendothelial deposition of extracellular matrix (ECM). Clinically, advanced disease leads to corneal edema with subsequent reduction in visual acuity. In the majority of patients with advanced FECD, a fibrillar layer (FL) appears on the posterior corneal surface. This FL is mostly localized in the inferotemporal corneal quadrant, marks areas with significantly reduced endothelial cell density and increased corneal thickness in the sense of edema and can be visualized and measured using Scheimpflug backscatter analysis due to increased backscatter. FECD is currently the most common indication for corneal transplantation worldwide, usually in the form of Descemet membrane endothelial keratoplasty (DMEK). New treatment approaches include variations of DMEK surgery such as hemi- or quarter DMEK with individualized and smaller grafts or Descemet membrane stripping only (DSO). In the future, clinical imaging of the FL as a particularly affected endothelial area could be important for FECD progression assessment and planning of surgical interventions. This article provides an overview of the current state of research on the clinical aspects, pathogenesis, fibrillar layer and individualized treatment of FECD.

[EndoArt®: results in patients with glaucoma drainage devices]. / EndoArt®: Ergebnisse bei Patienten mit Glaukom-Drainage-Implantaten.

BACKGROUND: EndoArt® (Eye Yon Medical, Ness Ziona, Israel) is a novel artificial corneal inner layer transplant and an innovative treatment alternative for patients at high risk for graft failure after posterior lamellar corneal transplantation (EK). AIM OF THE STUDY: We present the initial results of the EndoArt® implantation in patients with glaucoma drainage devices (GDD). PATIENTS AND SURGICAL PROCEDURE: In this study 12 eyes with GDD were retrospectively evaluated. All had a high risk of transplant rejection in cases of EK (previous other glaucoma surgery in addition to GDD, n = 8, condition following Descemet membrane endothelial keratoplasty, DMEK, n = 9, uveitis, n = 2, or synechiae, n = 2). The EndoArt® was secured with a gas bubble and one to three holding sutures. The preoperative and postoperative best spectacle-corrected visual acuity (BSCVA) and central corneal thickness (CCT) were determined. The need for additional gas injections (rebubbling) was analyzed. RESULTS: Octafluoropropane (C3F8) 12% was used in nine patients and sulfur hexafluoride (SF6) 20% in three patients as anterior chamber tamponade to ensure adhesion of the EndoArt®. At least one rebubbling was necessary in four eyes. The preoperative BSCVA was 1.6 (±â€¯0.5) logMAR and significantly improved to 1.1 (±â€¯0.6) logMAR after 12 weeks (p = 0.028). The preoperative CCT was 719 µm ± 145.7, which significantly decreased to 622.4 µm ± 174.9 after six weeks (p = 0.004) and to 591.7 µm ± 190.8 after 12 weeks (p = 0.096). In one eye, the prosthesis was explanted due to a suspected fibrotic remodelling of the cornea following multiple previous DMEKs. DISCUSSION: EndoArt® led to a significant improvement in BSCVA and reduction in CCT; however, there was a high rebubbling rate in patients with GDD. In high-risk patients, the use of EndoArt® may be advantageous in avoiding graft failure after EK.

Anti-Inflammatory and Anti-(Lymph)angiogenic Properties of an ABCB5+ Limbal Mesenchymal Stem Cell Population.

Corneal transparency and avascularity are essential for vision. The avascular cornea transitions into the vascularized conjunctiva at the limbus. Here, we explore a limbal stromal cell sub-population that expresses ABCB5 and has mesenchymal stem cell characteristics. Human primary corneal stromal cells were enriched for ABCB5 by using FACS sorting. ABCB5+ cells expressed the MSC markers CD90, CD73, and CD105. ABCB5+ but not ABCB5- cells from the same donor displayed evidence of pluripotency with a significantly higher colony-forming efficiency and the ability of trilineage differentiation (osteogenic, adipogenic, and chondrogenic). The ABCB5+ cell secretome demonstrated lower levels of the pro-inflammatory protein MIF (macrophage migration inhibitory factor) as well as of the pro-(lymph)angiogenic growth factors VEGFA and VEGFC, which correlated with reduced proliferation of Jurkat cells co-cultured with ABCB5+ cells and decreased proliferation of blood and lymphatic endothelial cells cultured in ABCB5+ cell-conditioned media. These data support the hypothesis that ABCB5+ limbal stromal cells are a putative MSC population with potential anti-inflammatory and anti-(lymph)angiogenic effects. The therapeutic modulation of ABCB5+ limbal stromal cells may prevent cornea neovascularization and inflammation and, if transplanted to other sites in the body, provide similar protective properties to other tissues.

Decreased vision due to scarring after phototherapeutic keratectomy.

In May 2023, a 36-year-old carpenter complained of a sudden decrease in visual acuity in both eyes after his fourth COVID-19 vaccination. He underwent extensive evaluation by ophthalmological, neurological, and internal medicine specialists elsewhere, which was unremarkable, except for a computed tomography scan of his brain showing minor occipital calcifications. In 2021, he had been diagnosed with anterior basement membrane dystrophy and treated with phototherapeutic keratectomy (PTK) of the left eye, leading to significant postoperative haze. On referral in July 2023, slitlamp examination showed significant anterior basement membrane dystrophy in the right eye, whereas the left eye had an extensive central scar in the anterior stroma, measuring up to 6 mm in width and 140 µm in depth (Figures 1-3JOURNAL/jcrs/04.03/02158034-202410000-00017/figure1/v/2024-09-18T130724Z/r/image-tiffJOURNAL/jcrs/04.03/02158034-202410000-00017/figure2/v/2024-09-18T130724Z/r/image-tiffJOURNAL/jcrs/04.03/02158034-202410000-00017/figure3/v/2024-09-18T130724Z/r/image-tiff). His corrected distance visual acuity was 20/80 in his right eye and 20/200 in his left eye, with a manifest refraction of -0.50 -3.75 × 170 and +0.00 -4.75 × 180, respectively. Corneal Scheimpflug topography showed regular corneal astigmatism of 3.3 diopters (D) and 5.5 D in the right and left eyes, respectively, with a corneal thickness of 550 and 566 µm (Figure 4JOURNAL/jcrs/04.03/02158034-202410000-00017/figure4/v/2024-09-18T130724Z/r/image-tiff). The Schirmer tear test was 20-20 mm. Fundoscopy, electrophysiological testing, and retinal optical coherence tomography (OCT) showed no abnormalities. The patient mentioned he had Crohn disease, managed with ustekinumab (a monoclonal antibody inhibitor of cytokines interleukin [IL]-12 and IL-23), but he had discontinued it because of the apparent remission of the disease. Attempts to improve visual acuity involved a soft bandage contact lens in the right eye, which was discontinued after 2 days because of the occurrence of a small corneal infiltrate that healed with a short course of topical antibiotics. Unfortunately, because of his vision, he cannot perform his tasks as a carpenter anymore. Which is your recommended treatment for both eyes?

[Glaucoma drainage devices in patients following injector-assisted implantation of an artificial iris into the ciliary sulcus : Video article]. / Glaukom-Drainage-Implantate bei Patienten nach injektorgestützter Implantation einer künstlichen Iris in den Sulcus ciliaris : Videobeitrag.

OBJECTIVE OF SURGERY: The aim of this surgical technique is the implantation of a glaucoma drainage device (GDD) in eyes with aphakic glaucoma following injector-assisted implantation of an artificial iris into the ciliary sulcus. INDICATIONS: This atraumatic tube insertion technique can be performed during GDD implantation after implantation of an artificial iris into the ciliary sulcus. SURGICAL TECHNIQUE: Following injector-assisted implantation of an artificial iris into the ciliary sulcus of eyes, the iris can shift into the chamber angle. The GDD should be positioned in the quadrant in which the iridectomy is located. Otherwise, GDD implantation is not possible due to the resistance of the artificial iris. Alternatively, the artificial iris can be easily and non-traumatically rotated in the ciliary sulcus by flushing the anterior chamber with balanced salt solution (BSS) to move the iridectomy into the desired area and position the GDD tube in the anterior chamber. A surgical video, which is available online, shows the surgical technique in detail. FOLLOW-UP: After GDD, dexamethasone eye drops should be applied 8 times daily for 1 week tapering down by 1 drop per week thereafter. Antibiotic eye drops, e.g., ofloxacin eye drops, are prescribed 4 times daily for 1 week and might be discontinued thereafter. EVIDENCE: To date, this is the first description of a rotation of an artificial iris located in the ciliary sulcus by irrigation of the anterior chamber during GDD implantation.

A Novel Symptomatic Lecithin-Cholesterol Acyltransferase Gene Mutation With Corneal Amyloidosis.

PURPOSE: To present ocular clinical, histological, systemic, and genetic findings of a patient with familial lecithin-cholesterol acyltransferase (LCAT) deficiency caused by a novel genetic variant of the LCAT gene associated with secondary corneal amyloidosis. METHODS: Case report. RESULTS: A 74-year-old woman presented with decreased visual acuity (VA), sensitivity to light, and progressive whitening of both corneas for approximately 20 years. The patient had undergone penetrating keratoplasty (PKP) on the right eye 6 years ago. Ophthalmologic examination revealed decreased VA in both eyes (OD: 0.05, OS: 0.3), and even further reduced glare VA (OD: 0.05, OS: 0.1), diffuse whitish corneal opacity involving the total thickness of the corneal stroma without crystalline deposits, and a marked peripheral diffuse arcus. Systemic examination revealed severely reduced plasma high-density lipoprotein cholesterol levels, target cells in blood smear, and chronic normochromic anemia. Clinically, LCAT deficiency was the most likely diagnosis. Further genetic analysis confirmed the diagnosis. The patient is homozygous for the novel variant c.943T>C (p.Trp315Arg) in the LCAT gene. Histologic examination of the cornea removed during the first keratoplasty revealed amyloid deposits. The cornea removed at the second keratoplasty had small vacuoles in the anterior stroma, indicating recurrence of lipid deposition. CONCLUSIONS: LCAT deficiency is a rare genetic disorder that can cause corneal opacities because of lipid deposition in the cornea. Systemic manifestations may help in the differential diagnosis to other diseases associated with severe high-density lipoprotein cholesterol reduction. Genetic analysis is employed to confirm the diagnosis. Some mutations in the LCAT gene seem to be associated with secondary corneal amyloidosis. Further investigation of this association is warranted. A recurrence of corneal opacity after PKP seems to occur mainly in the anterior corneal stroma.

Selective, Temporary Postoperative Inhibition of Lymphangiogenesis by Integrin α5ß1 Blockade Improves Allograft Survival in a Murine Model of High-Risk Corneal Transplantation.

Background: Corneal inflammatory hem- and lymphangiogenesis significantly increase the risk for immune rejection after subsequent allogeneic corneal transplantation. The purpose of this study was to analyze the impact of temporary selective inhibition of lymphangiogenesis after transplantation on graft survival. Methods: Allogeneic transplantation from C57BL/6 mice to BalbC mice was performed as "high-risk" keratoplasty in a prevascularized corneal host bed (suture-induced inflammatory corneal neovascularization). The treatment group received integrin α5ß1-blocking small molecules (JSM6427) at the time of transplantation and for two weeks afterwards. Control mice received a vehicle solution. Grafts were evaluated weekly for graft rejection using an opacity score. At the end of the follow-up, immunohistochemical staining of corneal wholemounts for lymphatic vessels as well as CD11b+ immune cells was performed. Results: Temporary postoperative inhibition of lymphangiogenesis by JSM6427 improved the corneal graft survival significantly. At the end of the follow-up, no significant reduction in CD11b+ immunoreactive cells within the graft compared to controls was found. Conclusions: The significant improvement of corneal graft survival by the selective, temporary postoperative inhibition of lymphangiogenesis after keratoplasty using integrin antagonists shows the impact of lymphatic vessels in the early postoperative phase. Retarding lymphatic vessel ingrowth into the graft might be sufficient for the shift to immunological tolerance in the postoperative period, even after high-risk keratoplasty.

Genetic Testing of Patients with Inherited Retinal Diseases in the European Countries: An International Survey by the European Vision Institute.

INTRODUCTION: The purpose of this project was to explore the current standards of clinical care genetic testing and counseling for patients with inherited retinal diseases (IRDs) from the perspective of leading experts in selected European countries. Also, to gather opinions on current bottlenecks and future solutions to improve patient care. METHODS: On the initiative of the European Vision Institute, a survey questionnaire with 41 questions was designed and sent to experts in the field from ten European countries. Each participant was asked to answer with reference to the situation in their own country. RESULTS: Sixteen questionnaires were collected by November 2023. IRD genetic tests are performed in clinical care settings for 80% or more of tested patients in 9 countries, and the costs of genetic tests in clinical care are covered by the public health service to the extent of 90% or more in 8 countries. The median proportion of patients who are genetically tested, the median rate of genetically solved patients among those who are tested, and the median proportion of patients receiving counseling are 51-70%, 61-80%, and 61-80%, respectively. Improving the education of healthcare professionals who facilitate patient referrals to specialized centers, improving access of patients to more thorough genotyping, and increasing the number of available counselors were the most advocated solutions. CONCLUSION: There is a significant proportion of IRD patients who are not genetically tested, whose genetic testing is inconclusive, or who do not receive counseling. Educational programs, greater availability of state-of-the-art genotyping and genetic counselors could improve healthcare for IRD patients.

Ophthalmological research in Germany: suggestions by an international expert panel.

PURPOSE: To evaluate the research performance in ophthalmology in Germany based on the findings of the recent research map of the German Ophthalmological Society (DOG) and to suggest strategies for future improvements on a national level both to DOG as well as to politics. The focus is on preclinical and translational clinical research. METHODS: International expert panel evaluation and discussion organized by the Task Force Research of the German Ophthalmological Society (DOG). RESULTS: The international view on the German ophthalmological research landscape was generally positive. The value for money relationship was judged as very good. As Germany is facing an aging society and vision impairment will create an ever-increasing socioeconomic burden, the reviewers suggested several lines of future activities: an increased activity of securing intellectual property, more lay audience lobbying, intensified collaboration and critical mass building between "lighthouses" of ophthalmic research in Germany, as well as the establishment of a German national eye institute equivalent. CONCLUSION: The ophthalmological research performance in Germany was rated to be very good by an international expert panel. Nonetheless significant improvements were requested in the fields of translation (clinical trials, IP), synergy between specialized institutions and governmental funding for a German center for eye research.

[Ophthalmological research in Germany: evaluation by an international expert panel]. / Ophthalmologische Forschung in Deutschland: Evaluation durch ein internationales Expertengremium.

PURPOSE: To evaluate the research performance in ophthalmology in Germany based on the findings of the recent research map of the German Ophthalmological Society ( DOG) and to suggest strategies for future improvements on a national level both to DOG as well as to politics. The focus is on preclinical and translational clinical research. METHODS: International expert panel evaluation and discussion organized by the Task Force Research of the German Ophthalmological Society (DOG). RESULTS: The international view on the German ophthalmological research landscape was generally positive. The value for money relationship was judged as very good. As Germany is facing an aging society and vision impairment will create an ever-increasing socioeconomic burden, the reviewers suggested several lines of future activities: an increased activity of securing intellectual property, more lay audience lobbying, intensified collaboration and critical mass building between "lighthouses" of ophthalmic research in Germany, as well as the establishment of a German national eye institute equivalent. CONCLUSION: The ophthalmological research performance in Germany was rated to be very good by an international expert panel. Nonetheless significant improvements were requested in the fields of translation (clinical trials, IP), synergy between specialized institutions and governmental funding for a German center for eye research.

Retinal Detachment Rates After Uncomplicated DMEK Versus Cataract Surgery Combined (Triple-)DMEK.

PURPOSE: To evaluate the rate of and risk factors for rhegmatogenous retinal detachment (RRD) after Descemet membrane endothelial keratoplasty (DMEK) either alone or in combination with cataract surgery. DESIGN: Retrospective analysis of prospective database. METHODS: Consecutive eyes with Fuchs endothelial corneal dystrophy (FECD) that received DMEK surgery with a minimum follow-up of 1 year between July 2011 and January 2021 at the Department of Ophthalmology at the University of Cologne were analyzed. Exclusion criteria were complicated history including repeat DMEK within 1-year, previous retinal or glaucoma surgery, complicated phacoemulsification, congenital cataract, history of trauma. RESULTS: From 3858 consecutive DMEKs, 1961 patients were identified suitable for analysis. 846 (43.1%) were pseudophakic DMEK, 91 (4.6%) phakic DMEK and 1,024 (52.2%) combined with cataract surgery. RRD occurred in 13 eyes (12 patients). Within two years after DMEK RRD occurred in 0.49% and 0.47% after DMEK and DMEK with cataract surgery, respectively. Mean age of 59.24 ± 8.42 years with subsequent RRD was significantly lower than overall 68.81 ± 9.89 years (t-test two-tailed; p < 0.001). The spherical equivalent was -4.69 ± 3.98 D (range -9.00 to 0.5) in RRD after pseudophakic DMEK compared to -2.79 ± 3.54 D (range -7.5 to 0.75) in combined procedures. Re-bubbling had no influence on RRD rate. CONCLUSIONS: DMEK alone or in combination with cataract surgery showed similar postoperative RRD rates in the first two years, generally in the range of pseudophakic RRDs. Risk factors such as myopia and younger age could be identified. Re-bubbling has no influence on RRD rates.

Efficacy and safety of combined UV-light corneal crosslinking and fine-needle diathermy to regress pathological murine corneal (lymph)angiogenesis in vivo.

PURPOSE: To compare safety and efficacy of isolated and combined UV-light corneal crosslinking (CXL) and fine-needle diathermy (FND) to regress pathological corneal vessels in vivo. METHODS: Mice with inflamed and pathologically vascularized corneas received CXL or FND as monotherapy or a combination of both treatments. Corneal pathological blood and lymphatic vessels, immune cells and the morphology of anterior segment structures were evaluated. RESULTS: All three approaches were able to regress blood and lymphatic vessels in mice. A comparative analysis of the three methods revealed that the FND monotherapy and the CXL + FND combination were significantly more effective than the CXL monotherapy, one and 2 weeks after therapy and especially in regressing lymphatic vessels. Furthermore, the combination therapy induced significantly less immune cell recruitment compared to the monotherapies. All three methods were safe to use in regards of corneal integrity. CONCLUSIONS: A combination of FND and CXL led to regression of pathological corneal lymphatic and blood vessels and reduced the infiltration of immune cells into inflamed murine corneas. This approach offers a new effective, safe and clinically usable strategy to treat eyes with mature pathological blood vessels and even more so for lymphatic vessels, for example prior to high-risk corneal transplantation.

Increased Anti-Inflammatory Therapeutic Potential and Progenitor Marker Expression of Corneal Mesenchymal Stem Cells Cultured in an Optimized Propagation Medium.

There is a huge unmet need for new treatment modalities for ocular surface inflammatory disorders (OSIDs) such as dry eye disease and meibomian gland dysfunction. Mesenchymal stem cell therapies may hold the answer due to their potent immunomodulatory properties, low immunogenicity, and ability to modulate both the innate and adaptive immune response. MSC-like cells that can be isolated from the corneal stroma (C-MSCs) offer a potential new treatment strategy; however, an optimized culture medium needs to be developed to produce the ideal phenotype for use in a cell therapy to treat OSIDs. The effects of in vitro expansion of human C-MSC in a medium of M199 containing fetal bovine serum (FBS) was compared to a stem cell medium (SCM) containing knockout serum replacement (KSR) with basic fibroblast growth factor (bFGF) and human leukemia inhibitory factor (LIF), investigating viability, protein, and gene expression. Isolating populations expressing CD34 or using siRNA knockdown of CD34 were investigated. Finally, the potential of C-MSC as a cell therapy was assessed using co-culture with an in vitro corneal epithelial cell injury model and the angiogenic effects of C-MSC conditioned medium were evaluated with blood and lymph endothelial cells. Both media supported proliferation of C-MSC, with SCM increasing expression of CD34, ABCG2, PAX6, NANOG, REX1, SOX2, and THY1, supported by increased associated protein expression. Isolating cell populations expressing CD34 protein made little difference to gene expression, however, knockdown of the CD34 gene led to decreased expression of progenitor genes. C-MSC increased viability of injured corneal epithelial cells whilst decreasing levels of cytotoxicity and interleukins-6 and -8. No pro-angiogenic effect of C-MSC was seen. Culture medium can significantly influence C-MSC phenotype and culture in SCM produced a cell phenotype more suitable for further consideration as an anti-inflammatory cell therapy. C-MSC show considerable potential for development as therapies for OSIDs, acting through anti-inflammatory action.

Artificial Intelligence for Lamellar Keratoplasty. / Künstliche Intelligenz bei lamellierenden Keratoplastiken.

The training of artificial intelligence (AI) is becoming increasingly popular. More and more studies on lamellar keratoplasty are also being published. In particular, the possibility of non-invasive and high-resolution imaging technology of optical coherence tomography predestines lamellar keratoplasty for the application of AI. Although it is technically easy to perform, there are only a few studies on the use of AI to optimise lamellar keratoplasty. The existing studies focus primarily on the prediction probability of rebubbling in DMEK and DSAEK and on their graft adherence, as well as on the formation of a big bubble in DALK. In addition, the automated recording of routine parameters such as corneal oedema, endothelial cell density or the size of the graft detachment is now possible using AI. The optimisation of lamellar keratoplasty using AI holds great potential. Nevertheless, there are limitations to the published algorithms, in that they can only be transferred between centres, surgeons and different device manufacturers to a limited extent.

UV light-mediated corneal crosslinking as (lymph)angioregressive pretreatment to promote graft survival after subsequent high-risk corneal transplantation (CrossCornealVision): protocol for a multicenter, randomized controlled trial.

BACKGROUND: Good vision highly depends on the transparency of the cornea, which is the "windscreen" of the eye. In fact, corneal blindness due to transparency loss is the second most common cause of blindness worldwide, and corneal transplantation is the main cure. Importantly, the cornea is normally avascular but can secondarily be invaded by pathological (blood and lymphatic) vessels due to severe inflammation, and the survival prognosis of a corneal graft mainly depends on the preoperative vascular condition of the recipient's cornea. Whereas transplants placed into avascular recipient beds enjoy long-term survival rates of > 90%, survival rates significantly decrease in pathologically pre-vascularized, so-called high-risk recipients, which account for around 10% of all performed transplants in Germany and > 75% in lower and middle-income countries worldwide. METHODS: This parallel-grouped, open-randomized, multicenter, prospective controlled exploratory investigator-initiated trial (IIT) intends to improve graft survival by preconditioning pathologically vascularized recipient corneas by (lymph)angioregressive treatment before high-risk corneal transplantation. For this purpose, corneal crosslinking (CXL) will be used, which has been shown to potently regress corneal blood and lymphatic vessels. Prior to transplantation, patients will be randomized into 2 groups: (1) CXL (intervention) or (2) no pretreatment (control). CXL will be repeated once if insufficient reduction of corneal neovascularization should be observed. All patients (both groups) will then undergo corneal transplantation. In the intervention group, remaining blood vessels will be additionally regressed using fine needle diathermy (on the day of transplantation). Afterwards, the incidence of graft rejection episodes will be evaluated for 24 months (primary endpoint). Overall graft survival, as well as regression of corneal vessels and/or recurrence, among other factors, will be analyzed (secondary endpoints). DISCUSSION: Based on preclinical and early pilot clinical evidence, we want to test the novel concept of temporary (lymph)angioregressive pretreatment of high-risk eyes by CXL to promote subsequent corneal graft survival. So far, there is no evidence-based approach to reliably improve graft survival in the high-risk corneal transplantation setting available in clinical routine. If successful, this approach will be the first to promote graft survival in high-risk transplants. It will significantly improve vision and quality of life in patients suffering from corneal blindness. TRIAL REGISTRATION: ClinicalTrials.gov NCT05870566. Registered on 22 May 2023.

Influence of Donor Factors on Descemet Membrane Endothelial Keratoplasty (DMEK) Graft Preparation Outcome.

Purpose: To determine which donor characteristics, like previous diseases and surgeries, influence the severity of the DM/endothelial lamella preparation prior to DMEK-surgery. Patients and Methods: Retrospective cross-sectional single-center study is presented. Eight hundred and forty-six eyes with DMEK-surgery between 01/2018 and 01/2021 performed at the University Hospital Cologne, Germany, were included. Information regarding the donors' previous diseases and surgeries were provided by a large database of a cornea bank (Multi Tissue Bank Mecklenburg-Vorpommern) and merged with the Cologne DMEK database, which contains information regarding preparation characteristics of the surgeon-prepared graft directly preoperatively. Three preparation groups (easy, difficult and very difficult) were correlated to the donors' previous diseases and surgeries. The following characteristics were used for the assignment in one of the three groups: stripping difficulty, rolling and staining behavior, central and peripheral adherences, tissue fragility and DM-splitting. Results: Significant risk factors for DM-splitting were diabetes mellitus (DMel) type II, heart failure, chronic kidney disease and previous cataract surgery (p=0.022, p=0.012; p=0.047 and p<0.001 respectively). Previous DMel (especially type 2) was significantly associated with the occurrence of central adherences (p=0.009). Several cardiovascular diseases (p-values between <0.001 and p=0.038), DMel type II, chronic kidney disease and previous cataract-surgery were associated with peripheral adherences (p=0.004; p=0.020 and p<0.001 respectively). Furthermore, pseudophakic donor eyes presented a higher degree of fragility of the graft (p<0.001). Age was a significant risk factor for difficult preparation (p<0.001). The staining of the graft was poorer in donors with chronic kidney disease (p=0.037). Conclusion: Donor diabetes mellitus type 2, heart failure, previous cataract surgery, chronic kidney disease and age are associated with a difficult DMEK graft preparation. For every one-year increment in donor age, the odds of having very difficult preparation were increased by 3%. Also, chronic kidney disease predisposes to a poor tissue staining with trypan blue during preparation.

A comparative study of cystoid macula edema following glaucoma drainage device surgery versus trabeculectomy.

PURPOSE: To assess and compare the risk for development of cystoid macula edema (CME) after glaucoma drainage device (GDD) implantation versus conventional trabeculectomy with mitomycin (trab) for glaucoma. METHODS: Retrospective review of consecutive patients receiving trab or GDD implantation between 2016 and 2018. Inclusion criteria were availability of pre- and postoperative spectral domain optical coherence tomography (SD-OCT) of the macula. SD-OCT images were evaluated for presence of CME qualitatively, central subfield thickness (CST) and macular volume (MV). RESULTS: 73 eyes could be included, 42 received trab and 31 GDD surgery. Eyes receiving trab on average had 0.8 ± 0.8 previous intraocular operations, while eyes with GDD implantation had 3.1 ± 1.9 (p < 0.001). Occurrence of postoperative CME was significantly more frequent after GDD implantation (6 out of 31 (19.4%)) than after trab (2 out of 42 eyes = 4.8%), (p = 0.049). Mean preoperative CST as well as MV was comparable in both groups (CST before trab: 282.7 ± 23.0 µm, CST before GDD 284.2 ± 27.3 µm, p = 0.287; MV before trab: 7.8 ± 1.1 mm3, MV before GDD: 8.0 ± 0.8mm3, p = 0.305). Mean postoperative CST and MV were significantly higher after GDD (CST 338.5 ± 129.3 µm, MV 8.8 ± 2.6 mm3) than after trabeculectomy (CST 290.6 ± 60.2 µm, p = 0.038; MV 7.8 ± 1.2mm3, p = 0.039). CONCLUSIONS: In real-life conditions, GDD surgery seems to be associated with a higher risk to develop CME when compared to conventional trabeculectomy. This information may be helpful for glaucoma surgeons to advise the patients on postoperative risks of surgery.