Graft survival of Descemet membrane endothelial keratoplasty (DMEK) in corneal endothelial decompensation after glaucoma surgery.

PURPOSE: This study aims to assess the results, rebubbling rate, and graft survival after Descemet membrane endothelial keratoplasty (DMEK) with regard to the number and type of previous glaucoma surgeries. METHODS: This is a clinical retrospective review of 1845 consecutive DMEK surgeries between 07/2011 and 08/2017 at the Department of Ophthalmology, University of Cologne. Sixty-six eyes were included: group 1 (eyes with previous glaucoma drainage devices (GDD); n = 27) and group 2 (eyes with previous trabeculectomy (TE); n = 39). Endothelial cell loss (ECL), central corneal thickness, graft failure, rebubbling rate, and best spectacle-corrected visual acuity (BSCVA) up to 3 years after DMEK were compared between subgroups of patients with different numbers of and the two most common types of glaucoma surgeries either GDD or TE or both. RESULTS: Re-DMEK rate due to secondary graft failure was 55.6% (15/27) in group 1 and 35.9% in group 2. The mean graft survival time in group 1 was 25 ± 11 months and 31.3 ± 8.6 months in group 2 (p = 0.009). ECL in surviving grafts in group 1 was 35% (n = 13) at 6 months, 36% at 12 months (n = 8), and 27% (n = 4) at 2 years postoperatively. In group 2, ECL in surviving grafts was 41% (n = 10) at 6 months, 36% (n = 9) at 12 months, and 38% (n = 8) at 2 years postoperatively. Rebubbling rate in group 1 was 18.5% (5/27) and 35.9% (14/39) in group 2 (p = 0.079). CONCLUSION: Eyes with previous GDD had no higher risk for an increased rebubbling rate but a higher risk for a re-DMEK due to secondary graft failure with a mean transplant survival time of about 2 years. Compared to eyes with preexisting glaucoma drainage device, eyes after trabeculectomy had less secondary graft failures and a longer mean graft survival rate.

Impact of preoperative visual acuity on Descemet Membrane Endothelial Keratoplasty (DMEK) outcome.

PURPOSE: To evaluate whether and how preoperative visual acuity predicts visual acuity outcome after Descemet Membrane Endothelial Keratoplasty (DMEK). METHODS: One thousand eighty-four out of 1162 consecutive eyes having undergone DMEK alone or combined with cataract surgery (triple-DMEK) between July 2011 and February 2016 from the prospective Cologne DMEK database were included and analyzed retrospectively for correlations between pre- and postoperative visual acuity values at 1, 3, 6, and 12 months after transplantation. RESULTS: There is a significant correlation between pre- and postoperative visual acuity (VA) after (triple)-DMEK after 6 and 12 months (p = 0.005 and p = 0.011 respectively; Pearson's correlation coefficient 0.240 and 0.224). Preoperative VA below 20/100 leads to delayed and reduced final visual acuity results after 12 months (p < 0.001). However, defining an increase in VA > 0.1 logMAR as clinically relevant, we could not show any clinically relevant significant difference in the time needed to recover to final VA and in final VA. There is no significant difference for preoperative VA values above 20/40. The chance to reach postoperative VA above 20/25 is 40% for preoperative VA of 20/200, 50% for preoperative VA of 20/60 and > 60% for preoperative VA of 20/40. CONCLUSION: DMEK results in very good final postoperative visual acuity results even in eyes with very poor preoperative vision caused by corneal pathology. However, preoperative visual acuity values below 20/100 result in significantly poorer visual recovery, which suggests that there is benefit in performing surgery early enough before this value is reached. Preoperative visual acuity seems to be an adjuvant tool for the prediction of the final visual outcome after DMEK.

Specific mosaic KRAS mutations affecting codon 146 cause oculoectodermal syndrome and encephalocraniocutaneous lipomatosis.

Oculoectodermal syndrome (OES) and encephalocraniocutaneous lipomatosis (ECCL) are rare disorders that share many common features, such as epibulbar dermoids, aplasia cutis congenita, pigmentary changes following Blaschko lines, bony tumor-like lesions, and others. About 20 cases with OES and more than 50 patients with ECCL have been reported. Both diseases were proposed to represent mosaic disorders, but only very recently whole-genome sequencing has led to the identification of somatic KRAS mutations, p.Leu19Phe and p.Gly13Asp, in affected tissue from two individuals with OES. Here we report the results of molecular genetic studies in three patients with OES and one with ECCL. In all four cases, Sanger sequencing of the KRAS gene in DNA from lesional tissue detected mutations affecting codon 146 (p.Ala146Val, p.Ala146Thr) at variable levels of mosaicism. Our findings thus corroborate the evidence of OES being a mosaic RASopathy and confirm the common etiology of OES and ECCL. KRAS codon 146 mutations, as well as the previously reported OES-associated alterations, are known oncogenic KRAS mutations with distinct functional consequences. Considering the phenotype and genotype spectrum of mosaic RASopathies, these findings suggest that the wide phenotypic variability does not only depend on the tissue distribution but also on the specific genotype.

Blockade of CCR7 leads to decreased dendritic cell migration to draining lymph nodes and promotes graft survival in low-risk corneal transplantation.

The chemokine receptor CCR7 is essential for migration of mature dendritic cells (DCs) to the regional lymph nodes, and it has been shown that blocking of CCR7 improves graft survival after high-risk corneal transplantation in vascularized recipient corneas. However, it is so far unknown whether blocking of CCR7 reduces migration of DCs from the avascular cornea to the draining lymph nodes and whether this leads to improved graft survival also in the low-risk setting of corneal transplantation, which accounts for the majority of perforating transplantations performed. Therefore, in this study, pellets containing Freund's adjuvant and bovine serum albumin (BSA) conjugated to Alexa488 fluorescent dye were implanted into the corneal stroma of BALB/c mice to analyze antigen uptake by corneal DCs and their migration to the regional lymph nodes. After pellet implantation, mice were either treated by local administration of a CCR7 blocking fusion protein that consisted of CCL19 fused to the Fc part of human IgG1 or a control-IgG. In vivo fluorescence microscopy showed uptake of Alexa488-conjugated BSA by corneal DCs within 8 h. Furthermore, analysis of single cell suspensions of draining lymph nodes prepared after 48 h revealed that 2.1 ± 0.3% of CD11c(+) cells were also Alexa488(+). Importantly, DC migration was significantly reduced after topical administration of CCL19-IgG (1.2 ± 0.2%; p < 0.05). To test the effect of CCR7 blockade on graft rejection after allogeneic low-risk keratoplasty, corneal transplantations were performed using C57BL/6-mice as donors and BALB/c-mice as recipients. Treatment mice received two intraperitoneal loading doses of CCL19-IgG prior to transplantation, followed by local treatment with CCL19-IgG containing eye drops for the first two weeks after transplantation. Control mice received same amounts of control-IgG. Kaplan-Meier survival analysis showed that in the CCL19-IgG treated group, 76% of the grafts survived through the end of the 8 week observation period, whereas 38% of the grafts survived in the control group (p < 0.05). Taken together, our study shows that blockade of CCR7 reduces the migration of mature corneal DCs to the draining lymph nodes and leads to improved graft survival in low-risk corneal transplantation.

[Intraoperative Optical Coherence Tomography In Deep Anterior Lamellar Keratoplasty]. / Intraoperative optische Kohärenztomografie bei der tiefen anterioren lamellären Keratoplastik.

BACKGROUND: Like penetrating keratoplasty (pKPL), deep anterior lamellar keratoplasty (DALK) is a standard treatment for keratoconus and stromal corneal dystrophies. Intraoperative optical coherence tomography permits live or real-time monitoring during surgery, especially if it is necessary to estimate distances or if the anterior chamber view is limited. METHODS: Review of literature from PUBMED and our own clinical and experimental data. Key words were "intraoperative Optical Coherence Tomograph", "DALK", "Deep anterior lamellar keratoplasty" and "iOCT". The time frame was set from 2005 to 2016. RESULTS: All surgical steps were visualisable by intraoperative OCT during DALK surgery. Intraoperative OCT permits depth estimation during deep needle insertion and allows the visualisation of intraoperative interface fluid. CONCLUSION: Intraoperative OCT facilitates standardisation during several steps of DALK. Future prospective studies should concentrate on the safety profile of intraoperative OCT-guided DALK compared to DALK without intraoperative monitoring.

[Update Minimally Invasive Lamellar Keratoplasty: DMEK, DSAEK and DALK]. / Update minimalinvasive lamelläre Keratoplastik: DMEK, DSAEK und DALK.

BACKGROUND: The spectrum of operative interventions in corneal disorders requiring keratoplasty has been expanded considerably in recent years. In addition to the standard technique with full-thickness replacement of the cornea (perforating keratoplasty), lamellar techniques have been introduced. The aim of this review is to highlight current opportunities, indications and complications, as well as possible strategies to standardise lamellar keratoplasties. MATERIALS AND METHODS: Our own data and a review of the literature in PubMed are summarised. RESULTS: Performing "Descemet Membrane Endothelial Keratoplasty" (DMEK), "Descemt Stripping Automated Endothelial Keratoplasty" (DSAEK) and "Deep Anterior Lamellar Keratoplasty" (DALK) can provide patients with disorders of the corneal endothelium or the anterior corneal stroma with minimally invasive corneal grafts at a reduced risk of complications. CONCLUSION: DMEK and DSAEK are now internationally the surgical methods of choice in patients with endothelial corneal pathologies, i.e. in Fuchs' Endothelial Dystrophy. The DALK technique for lamellar replacement of the anterior stroma, i.e. in keratoconus, needs further standardisation, so that DALK can in future be performed more often even in less specialised departments. Major advantages of lamellar keratoplasties are the very good results in visual outcome and fewer immune reactions or graft rejections. Even intraoperative complications are rare. In the long term, further strategies are desirable for the standardisation of lamellar keratoplasties and its establishment as the primary standard procedure.

[Transcanalicular Laser Dacryocystorhinostomy: One-Year-Experience in the Treatment of Acquired Nasolacrimal Duct Obstructions]. / Transkanalikuläre Laserdakryozystorhinostomie--1-Jahres-Erfahrung in der Behandlung infrasakkaler Tränenwegsstenosen.

BACKGROUND: External dacryocystorhinostomy (DCR) is at present the gold standard for the surgical treatment of acquired nasolacrimal duct obstructions, but tremendous progress has been made in recent years in improving minimally invasive techniques, sparing not only the skin, but also the medial lid structures, which contribute to the physiological palpebral-canalicular pump mechanism. The purpose of this study is to report our 1-year experience with the surgical technique, complications and results of transcanalicular laser assisted DCR. PATIENTS AND METHODS: 48 consecutive transcanalicular laser-assisted DCRs combined with bicanalicular silicone intubation were performed for acquired nasolacrimal duct obstruction, and evaluated for intra- and postoperative complications, as well as subjective and objective success rates. RESULTS: Transcanalicular laser-assisted DCR combined with bicanalicular silicone intubation was surgically feasible in 45 cases (94 %). In 3 patients (6 %) it was impossible to position the aiming beam correctly at the anteroinferior rim of the middle turbinate using the superior canalicular approach, due to superior orbital rim prominence. Therefore 2 patients received no silicone intubation, despite a patent osteotomy at the back of the middle turbinate, and 1 patient underwent intraoperative conversion to external DCR due to anatomical narrowness of the nasal cavity. Perioperatively, 1 patient developed canalicular infection, 1 patient exhibited thermal injury to the canaliculus, and 4 patients exhibited premature prolapse of the silicone tube. At 6-months follow-up, functional success--defined as resolution of preoperative symptoms--was achieved in 35 of 45 surgically successful transcanalicular laser-assisted DCRs (78 %). Of the 10 postoperative failures (22 %), all patients reported epiphora, 6 patients were unable to irrigate the lacrimal drainage system, and 6 patients required surgical revision using external DCR. CONCLUSIONS: Transcanalicular laser assisted DCR is a promising minimally invasive approach for the surgical treatment of acquired nasolacrimal duct obstruction, in order to fill the gap between recanalising first step procedures and external DCR.

[Tumors of the lacrimal drainage system]. / Tumoren der ableitenden Tränenwege.

BACKGROUND: The prevalence of tumors affecting the lacrimal drainage system is low, thus generating a risk of late diagnosis and treatment in clinical routine. However, these tumors can be potentially life-threatening, which emphasizes the relevance of early diagnosis and treatment. OBJECTIVE: This review focuses on the symptoms, incidence, management, and prognosis of the different tumor entities affecting the lacrimal drainage system. METHODS: The study provides a PubMed-based literature review and presents own clinical results. RESULTS: Alongside detailed medical history taking and comprehensive clinical examination, precise inspection during external dacryocystography is important for diagnosis of tumors affecting the lacrimal drainage system. There is a wide spectrum of tumor entities located in the lacrimal drainage system. The tumors are classified into three groups: primary epithelial, primary nonepithelial, and inflammatory lesions. The most common primary epithelial tumors include papilloma, squamous cell carcinoma, and transitional cell carcinoma. The most common nonepithelial tumors include fibrous histiocytoma, malignant lymphoma, and malignant melanoma; while the most common inflammatory lesions comprise sarcoidosis, Wegener granulomatosis, and pyogenic granuloma. Treatment depends on the entity and stage of the tumor. In the case of malignancy, a multimodal and interdisciplinary approach is usually indicated. CONCLUSION: Differential diagnostic signs in favor of a malignancy include a long medical history, predisposing conditions in the patient's history, a mass above the medial canthal ligament, teleangiectasis above the mass, and serosanguinous secretion.

[Non-Invasive Diagnosis of Ocular Graft-versus-Host Disease]. / Nicht invasive Diagnostik der okulären Graft-versus-Host-Erkrankung.

Ocular graft-vs-host disease (GvHD) is a major complication following allogenic blood stem cell transplantation (aBSCT) leading to a disturbance of the ocular surface integrity with a broad range of severity. Leading symptom is a pronounced autoinflammatory reaction in particular at the ocular surface with typical features of dry eye disease. Potential complications include visual loss, pain and damage to the ocular structures with, e. g. corneal ulcerations. Diagnosis and treatment of ocular GvHD are a challenge for attending ophthalmologists and require intensive interdisciplinary patient care in particular with haemato-oncologists. First and follow-up examinations consist of several diagnostic steps that include quantitative and qualitative analysis of tearfilm, visual acuity, ocular surface and retinal integrity, cataract development and subjective symptoms. Available tests are mostly evaluated for usage in dry eye diagnosis but are, however, mostly unspecific for diagnosing ocular GvHD reliably. Only combinations of several clinical tests together with the experience of specialised ophthalmologists may lead to the certain diagnosis and treatment decisions at state. This review illustrates the available established and innovative non-invasive diagnostic tests and evaluates their potential use for diagnosing ocular GvHD.

[Patient-Centred Care of Ocular Graft-vs-Host Disease in Germany]. / Versorgungsstrukturen der okulären Graft-versus-Host Disease in Deutschland.

BACKGROUND: Ocular GvHD is a severe complication following allogenic blood stem cell transplantation leading to massive reduction in quality of life and ocular pathologies including corneal perforation. Interdisciplinary patient-centred care needs to be performed in specialized ophthalmic centers that provide all diagnostic and therapeutic options, however, only few clinics have the necessary infrastructure. In addition there is a lack of transparency and easily accessible information for the patients regarding ophthalmic care and specialized centres. For this reason the "Ocular GvHD working group" within the Cornea Section of the German Society of Ophthalmology has been founded to evaluate and improve patient-centered care in ocular GvHD within Germany. METHODS: A survey was performed among the members of the Cornea Section of the German Society of Ophthalmology and the Directors of Departments of Ophthalmology in Germany that evaluated the number of annual examinations, presence of specialized GvHD outpatient clinics and eye screenings prior to allogenic blood stem cell transplantation (aBSCT). RESULTS: 25 clinics (19 university hospitals, 6 general hospitals) responded to the survey. In 18 clinics aBSCT are performed. Between 5 and 200 patients after aBSCT are examined per year per clinic. Larger institutions are associated with departments of haemato-oncology and other specialised disciplines to facilitate an interdisciplinary patient care. Three clinics are associated with GvHD competence centres. The major challenge in establishing an appropriate infrastructure for better patient-centered care is the limited or lacking reimbursement by health insurances. CONCLUSIONS: Within Germany only few ophthalmic centres exist that provide state-of-the-art patient-centered care for ocular GvHD. The present structures are not sufficient to treat all patients undergoing aBSCT following existing guidelines. Joint efforts are necessary to establish more and accessible competence centers for ocular GvHD with sufficient personnel and structural resources. In addition, ocular GvHD should be included as a mandatory topic in medical training and transparent and easily accessible information needs to be provided for patients and health-care professionals.

[Therapy for Ocular Graft-vs-Host Disease]. / Therapie der okulären Graft-versus-Host-Erkrankung.

Therapy for ocular graft-vs-host disease (ocular GvHD) is challenging for ophthalmologists as progress of the disease often occurs rapidly and is unforeseeable. Primary goal is the preservation or restoration of visual acuity, however, studies on ocular GvHD that have investigated therapeutic concepts are limited. In contrast, most therapeutic recommendations from consensus conferences derive from studies on dry eye diseases other than ocular GvHD. This review demonstrates the available therapies in the following categories: local, systemic, surgical and prophylactic. Primary targets are anti-inflammation, anti-fibrosis and lubrification of the ocular surface. In conclusion, studies strictly on ocular GvHD are needed to enable better evidence-based therapeutic decision-making in the future.

[Basic immunology and current therapeutic concepts in ocular allergy]. / Grundlagen allergischer Erkrankungen der Augenoberfläche und aktuelle medikamentöse Therapiekonzepte.

BACKGROUND: Ocular allergy belongs to the most common ocular diseases globally. Following clinical phenotype and immunopathogenesis different forms of allergy are distinguished, which require different forms of therapeutic approach. This manuscript reviews the basic immunological processes involved in the development of ocular allergies and current and future therapeutic approaches. METHODS: Results of a literature search in PubMed and our own clinical and experimental experience are presented. RESULTS: In the immunopathogenesis of ocular allergy different immune cells such as dendritic cells, B-cells, T-cells, mast cells, eosinophils and regulatory T-cells are involved. Therapeutic approaches focus on either relief of symptoms using antihistamins or mast cell stabilisers or combinations of both. In severe cases steroids or calcineurin inhibitors are used. DISCUSSION: Despite great progress in the investigation of ocular allergy in the past decade several open questions remain, such as the relation of ocular allergy with dry eye disease. Future therapeutic approaches will likely be based on recently identified new aspects such as lymphangiogenesis and will allow better and potentially causal treatment of ocular allergy.

[Corneal cross-linking in microbial keratitis to prevent à chaud keratoplasty: a retrospective case series]. / Antimikrobielles Crosslinking der Hornhaut zur Vermeidung der Keratoplastik à chaud: retrospektive Fallserie.

BACKGROUND: Corneal cross-linking (CXL) with riboflavin is being used more frequently for the treatment of therapy-resistant microbial keratitis, since increasing drug resistance and specific pathogens, e.g. contact lens-associated Acanthamoeba, make this therapy appear as an attractive option to avoid a keratoplasty à chaud. PATIENTS AND METHODS: This retrospective case series of 11 consecutive patients (4 women, 7 men, aged 24-82 years) who received standardised antimicrobial CXL for therapy-resistant keratitis to avoid a keratoplasty à chaud, included 4 cases with detection of bacterial pathogens, one case with proven fungal infection and 6 cases without pathogen detection. Analysed data comprised ophthalmic medical history, general risk factors for microbial keratitis, treatment before and after CXL. The characterisation of the corneal ulcer included photometric measurements of the infiltrates with a median of 16.2 mm² and four unmeasurable cases due to extended, not circumscribed lesions. RESULTS: Within the follow-up period (mean 134 ± standard deviation 82 days), a penetrating keratoplasty was successfully avoided in 6 patients (55 %). After CXL 9 patients (82 %) received additionally amniotic membrane transplantation. After CXL treatment, topical antibiotic therapy was continued for a mean 27 ± 13 days postoperatively. Steroids were applied in 91 % of the patients. The cornea cleared at least to some extent in 9 patients (82 %). Patients with neurotrophic keratopathy or potentially compromised immune system showed no increased failure rate. CONCLUSION: These results suggest that antimicrobial CXL might be a useful option in patients with therapy-resistant corneal ulcer in order to avoid a perforating keratoplasty à chaud. For a comprehensive scientific assessment of this therapy, however, further, ideally prospective randomised interventional studies with large sample sizes are needed.

[Innovative surgical treatment approaches for endothelial dysfunction : Descemet stripping only (DSO) and endothelial cell injection]. / Innovative chirurgische Therapieansätze der endothelialen Dysfunktion : "Descemet stripping only" (DSO) und Endothelzellinjektion.

Currently, due to a rising number of patients Germany and many other countries experience a large deficit of donor eyes for posterior lamellar keratoplasty procedures in the treatment of corneal endothelial diseases. To address this unmet need there is an ongoing investigation of treatment modalities which do not rely on donor tissue or enable clinicians to treat more patient eyes per donor eye. The authors introduce a promising approach for both treatment principles. First, the technique of Descemet stripping only (DSO) is detailed, in which a central part of the Descemet's membrane including the endothelium is surgically removed without replacement with donor tissue. This then allows endothelial cells from the periphery of the cornea to migrate into the central area and can reduce corneal opacification and swelling. As a representative technique of the second group, the authors introduce endothelial cell injection, in which human corneal endothelial cells are cultivated in vitro and then, after removal of the diseased endothelium, injected into the anterior chamber of the recipient's eye to form a new and healthy endothelium. This is supported by injection of Rho kinase inhibitors and a face-down positioning of the patient after surgery. It is postulated that endothelial cell injection could possibly enable clinicians to treat up to 300 patient eyes with the tissue generated from 1 donor eye. Whether and how these novel approaches will become established in Europe remains to be seen.

[Predictive parameters for anatomical surgical success in full-thickness macular holes : A retrospective evaluation of 391 eyes]. / Prädiktive Parameter für den anatomischen Operationserfolg bei durchgreifenden Makulaforamina : Eine retrospektive Auswertung von 391 Augen.

BACKGROUND: Full-thickness macular hole (FTMH) is a rare disease. Not all FTMHs can be closed by primary surgical intervention. OBJECTIVE: This work aims to characterize a large patient population with FTMHs and to detect possible predictive factors for anatomical treatment success. MATERIALS AND METHODS: The study comprises a retrospective analysis of all consecutive idiopathic macular holes between March 2008 and June 2019 at the University Eye Hospital Cologne. Epidemiologic data, preoperative parameters (size of the FTMH), and surgical technique were examined in relation to the closure rate following primary surgery. RESULTS: The anatomical closure rate for idiopathic FTMH after primary surgery was 83.6%. No association between age, gender, and lens status and closure rate could be shown. Regarding anatomical surgical success, the favorable prognostic factors identified were a small FTMH size, short symptom duration, performance of transconjunctival 23-gauge vitrectomy, and application of the inverted flap technique of the internal limiting membrane (ILM). CONCLUSION: Surgical treatment represents a valuable treatment option for patients with macular holes due to good prospects of success. Prompt intervention after diagnosis using 23-gauge vitrectomy and an ILM flap with gas tamponade seems to result in the most favorable outcomes.

"OSMO-UT-DSAEK" using THIN-C medium.

BACKGROUND: When performing ultra-thin Descemet's stripping automated endothelial keratoplasty (UT-DSAEK), the quality of the stromal interface and stromal thickness seem to be critical for visual outcome. The aim of this study was to investigate whether additional osmotic deswelling prior to UT-DSAEK improves the quality of the cut surface and leads to a more reliable and deeper cut in UT-DSAEK ("OSMO-UT-DSAEK"). METHODS: Seventeen human donor corneas not usable for transplantation were used in this experiment. After standard deswelling with culture Medium II, ten corneas were randomly assigned to be additionally deswollen within THIN-C medium. The other remaining seven corneas were put back into culture Medium II. All corneas were placed in an artificial anterior chamber system (Moria); a double path cutting procedure using a microkeratome (Moria) was then performed. Corneal thickness was measured by ultrasound biomicroscopy and in paraffin-embedded slides, followed by histological grading of the cut surface. RESULTS: Stromal interface smoothness significantly improved after preconditioning in THIN-C medium (Pearson P = 0.019). The correlation of the corneal thickness obtained by UBM (mean 706 ± SD 208 µm) and histology (mean 530 ± SD 159 µm) was not significant (Pearson r = 0.11, P > 0.05, mean difference 247, 95 % CI [+50;+304]). We found no significant correlation between the microkeratome setting and the actual thickness of the lenticule measured in histological analysis in both media as well as for the first and second cut (first cut: Pearson r = 0.9, P = 0.1, 95 % CI [-10;+96], second cut: Pearson r = 0.9, P = 0.4, 95 % CI [-10;+22]). CONCLUSION: Preconditioning of corneas with THIN-C medium significantly improved the quality of the graft interface in UT-DSAEK, but did not significantly improve the cut precision of the microkeratome.

[Immune reactions after DMEK, DSAEK and DALK]. / Immunreaktionen nach DMEK, DSAEK und DALK.

PURPOSE: The aim of this study is to describe incidence, diagnosis and therapy for endothelial immune reactions after modern lamellar corneal transplantat surgery (DMEK, DSAEK, DALK). METHODS: A PubMed-based literature review and our own clinical and experimental data are evaluated. RESULTS: There is no longer an endothelial immune reaction after DALK for keratoconus. DMEK significantly reduces the risk for endothelial immune reactions after surgery for Fuchs dystrophy. CONCLUSIONS: Modern lamellar corneal transplant techniques such as DALK and DMEK have nearly abolished the risk for endothelial immune reactions in the avascular recipient bed.

[Anti(lymph)angiogenic preconditioning prior to keratoplasty]. / Antiangiogene Präkonditionierung vor Keratoplastik.

PURPOSE: The aim of this study is to describe novel therapeutic concepts to promote graft survival in high-risk keratoplasty by targeting (lymph)angiogenesis in the transplant context. METHODS: A PubMed literature search and our own clinical and experimental data are evaluated. RESULTS: There are three options for anti(lymph)angiogenic preconditioning: a) primary prevention of neovascularisation during the disease process, b) secondary prevention by regressing established blood vessels prior to transplantation and (c) tertiary prevention through inhibition of post-keratoplasty neovascularisation. CONCLUSION: Modern topical anti(lymph)angiogenic therapies seem to be able to reduce the risk of graft rejection especially in high-risk keratoplasty.

[Anti-inflammatory treatment in dry eye disease]. / Antientzündliche Therapie beim Trockenen Auge.

Dry-eye is a multifactorial disease consisting of different pathomechanisms including instability of the tearfilm, increase of tearfilm osmolarity and most importantly inflammation of the ocular surface. In this context numerous signalling pathways and related immune mechanisms were identified all pointing towards autoimmune reactions as key parameters within this complex system. As autoimmunity tends to act independently from regulatory mechanisms, inhibition of related inflammatory processes is crucial in dry-eye therapy. Currently therapeutic agents such as steroids, cyclosporin, antibiotics, omega-3 and -6 fatty acids, etc. are available and readily used in daily practice. However, these therapies possess functional or legal restrictions that may limit their application. New strategies such as anti-lymphangiogenic therapies may have the potential to substitute or enhance current treatments. Independent of any anti-inflammatory therapy a detailed examination of the individual patient is necessary due to the complexity of the disease to provide individual and successful treatment.

[Split-cornea transplantation - a novel concept to reduce corneal donor shortage]. / Split-Cornea-Transplantation - ein neues Konzept gegen Spendermangel.

BACKGROUND: Penetrating keratoplasty is at present the gold standard for corneal transplantation, but tremendous progress has been made in recent years in improving lamellar keratoplasty techniques, such as deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK). The purpose of this report is to describe split-cornea transplantation by combining DALK and DMEK as a novel concept to reduce donor shortage. METHODS: The study consists of a PUBMED literature review and our own clinical results. RESULTS: Splitting of a single donor cornea into an anterior part (including epithelium, its basement membrane, Bowman layer, and stroma) for use in a DALK procedure in a patient with anterior-stromal disease (e. g., keratoconus) and into a posterior part (endothelium-Descemet membrane layer) for use in a DMEK procedure in a patient with endothelial disease (e. g., Fuchs endothelial dystrophy) can reduce the need for corneal donor tissue by around 50 %. A short-term 6-months follow-up has revealed good visual and refractive outcomes with low complication rates and acceptable endothelial cell loss. CONCLUSION: Split-cornea transplantation by combining DALK and DMEK surgeries is a promising concept to reduce donor shortage in corneal transplantation surgery in the future.