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The purpose of this study was to analyze the influence of patient positioning on intraocular pressure (IOP) after Descemet membrane endothelial keratoplasty (DMEK) in pseudophakic patients treated for Fuchs endothelial corneal dystrophy.Forty patients were included in this prospective, single-blinded, randomized controlled clinical trial. Patients received a YAG iridotomy 1 day before surgery and an 80% anterior chamber tamponade [20% concentration of sulfur hexafluoride (SF6)]. Postoperative positioning was either supine (group 1) or seated (group 2, at least 30 degrees upper-body high position). IOP was measured with iCare.There was no statistically significant difference in IOP postoperatively [group 1 vs. group 2-after 1h: 13.9 mm Hg (±4.2 mm Hg) versus 13.6 mm Hg (±4.1 mm Hg) (P = 1.00); after 2h: 13.9 mm Hg (±5.4 mm Hg) versus 15.3 mm Hg (±4.6 mm Hg) (P = 0.370); after 4h: 13.8 mm Hg (±4.2 mm Hg) versus 15.2 mm Hg (±4.2 mm Hg) (P = 0.401]. In group 1, 10% of patients showed IOP decompensations well above 30 mm Hg, and in group 2, there were no IOP decompensations. Seated position led to relative risk reduction of 100% and absolute risk reduction of 10% regarding IOP decompensations. The number of patients needed to position seated to prevent 1 additional IOP decompensation was 10. Rebubbling rates, best spectacle-corrected visual acuity, and reduction of corneal thickness were comparable between the 2 groups in the follow-up period up to 1 month.After DMEK in pseudophakic eyes with 80% anterior chamber tamponade, positioning patients with at least 30 degrees elevation of the upper body up immediately after surgery until bedtime prevents IOP decompensations.

Intraoperative optical coherence tomography (OCT) was so far only available as a microscope-integrated or handheld device. Recently, this technology has been integrated into a femtosecond (FS) laser. This pilot study analyzed the potential of intraoperative imaging using OCT during FS-assisted procedures of the anterior eye segment. Therefore, intraoperatively acquired videos using FS-integrated intraoperative OCT (laser-integrated [LI] OCT) in 14 patients (Victus, Bausch & Lomb) were analyzed in different surgical procedures. The results showed that all surgical steps could be successfully visualized by LI-OCT. LI-OCT added important information regarding the depth and location of the incisions and dissection planes. Moreover, dynamic processes could be observed in real-time. LI-OCT represents a new imaging technology that makes it possible to visualize intraoperative steps during FS-assisted surgery. In the future, automatic image analysis based on artificial intelligence could be helpful to detect complications at an early stage and to automatically stop the laser process in relevant constellations.

Das Risiko der Abstosung und des Transplantatversagens nach Hochrisikokeratoplastik steigt mit Zunahme der kornealen Neovaskularisation. Die medikamentose und physikalische Regression der kornealen Neovaskularisation vor Keratoplastik bietet moglicherweise das Potenzial, das Risiko einer Abstosung nach anschliesender Hochrisikokeratoplastik zu reduzieren. Die vorliegende Arbeit gibt eine Literaturubersicht hinsichtlich der Prakonditionierung von vaskularisierten Hochrisikoaugen mittels Feinnadeldiathermie und kornealem Crosslinking vor Hochrisikokeratoplastik („lymphangioregressive Prakonditionierung“). Es erfolgen eine Literaturrecherche via PubMed sowie eine Zusammenfassung eigener Daten. Tierexperimentelle Studien zeigen, dass sowohl die Feinnadeldiathermie als auch das korneale Crosslinking zu einer Regression der kornealen Neovaskularisation fuhren und das Transplantatuberleben nach anschliesender Hochrisikokeratoplastik verlangern. Untersuchungen aus unserem Institut geben daruber hinaus erste Hinweise, dass beide Verfahren auch in der klinischen Praxis zur Reduktion der kornealen Neovaskularisation fuhren und damit potenziell das Abstosungsrisiko reduzieren. Die Feinnadeldiathermie und das korneale Crosslinking bieten effektive Therapieansatze zur angioregressiven Behandlung und scheinen das Transplantatuberleben nach Hochrisikokeratoplastik zu verlangern. Groser angelegte prospektive und kontrollierte klinische Studien sind notwendig, um diese vielversprechenden Therapieansatze weitergehend zu untersuchen.

To evaluate a novel hydrophobic, non-diffractive, extended depth of focus (EDOF) intraocular lens (IOL) design in comparison to two monofocal aspheric lenses. Inclusion criteria for this prospective, monocentric cohort study were opacification of the crystalline lens and patients’ wishes for surgery. In the case of the EDOF IOL, patients asked for a presbyopia correction. All patients received surgery on both eyes. Corrected and uncorrected distance visual acuity (CDVA, UCDVA), uncorrected and distance corrected intermediate visual acuity (UIVA, DCIVA) and defocus curves (all monocular and binocular) were compared three months postoperatively. Fifty-six eyes were implanted with an EDOF IOL (LuxSmartTM, Bausch & Lomb GmbH, Berlin, Germany), 50 eyes with a monofocal aspheric IOL: 32 eyes with a clear IOL (Polylens® AS 61, Polytech Domilens, Roßdorf, Germany), 16 eyes with a yellow IOL (iSert® 251, Hoya Surgical Optics GmbH, Frankfurt, Germany). Three months postoperatively, UCDVA was comparable with the EDOF IOL, versus the monofocal IOL (P > 0.9). Binocular DCIVA in the EDOF IOL was significantly higher than in the monofocal IOL (P = 0.001). Monocular DCIVA better than 20/23 Snellen was achieved in 10% with the monofocal IOL and in 68% (P < 0.0001) with the EDOF IOL. Defocus curves showed a depth of focus at 20/23 Snellen of 1.6 vs. 0.83 diopters (D) in the EDOF IOL, vs. the monofocal IOL. No patient reported halos or starbursts in non-standardized questioning. This non-diffractive EDOF IOL provided comparably high UCDVA and significantly higher DCIVA than the mono-focal lenses, causing only mild optical phenomena.

Ocular involvement in mucous membrane pemphigoid (MMP) is relatively rare, with a prevalence of 25 cases per million population, equating to approx. 2,100 patients throughout Germany. Diagnosis can be difficult - especially in cases of isolated ocular involvement - and treatment can be complex and lengthy. Immunosuppressants or immunomodulatory drugs are often used. Due to the complexity of diagnosis and treatment, MMP patients are usually referred to specialized centers. The aim of this project was to evaluate the current care situation of patients with ocular MMP in Germany.A paper-based survey was designed and sent to all university eye clinics and other specialized centers in Germany in April 2020. The survey asked about the existence of a specialized outpatient service, the total annual number of patients with MMP, the annual number of newly diagnosed patients, any interdisciplinary collaboration for diagnostic or therapeutic purposes, as well as the local and systemic therapy used.Of a total of 44 clinics, 28 (64%) responded, reporting a total average of 27 ± 42 (0 - 200) patients and 3.6 ± 2.2 (0 - 10) new cases per year. This corresponds to a total of 741 patients. Only nine (32%) of the responding clinics offer specialized MMP clinics. 93% of the centers collaborate with the local dermatology department. 79% perform serological and histological diagnostics in-house. About half of the centers (n = 16) apply a standardized treatment regime. Systemic glucocorticoids (66.7%) are most commonly used, followed by mycophenolate mofetil and dapsone (57.1%), rituximab (33.3%), azathioprine and cyclophosphamide (28.6%), as well as methotrexate (19.0%). The least frequently used treatment is intravenous immunoglobulin (14.3%).This survey of German ophthalmology departments obtained data from about one third of the estimated total cohort of all patients with MMP in Germany. These are presumed to be exclusively patients with at least one ocular involvement. The complex care of these patients is usually provided in collaboration with a dermatologist and with the use of systemic anti-inflammatory medication. Currently, an ophthalmological MMP register is being established to better record the epidemiology and care situation of this rare disease in Germany and to improve it in the long term.Die okuläre Beteiligung bei vernarbendem Schleimhautpemphigoid (SHP) ist mit einer Prävalenz von 25 Fällen je 1 Mio. Einwohner und damit ca. 2100 Patienten in ganz Deutschland selten. Die Diagnosestellung kann – besonders in Abwesenheit anderer Beteiligungen – schwierig und die Therapie komplex und langwierig sein. Nicht selten kommen Immunsuppressiva zum Einsatz. Aufgrund der Komplexität von Diagnose und Therapie sind SHP-Patienten meist an entsprechend spezialisierte Zentren angebunden. Ziel dieses Projektes war die Erfassung der aktuellen augenärztlichen Versorgungssituation von Patienten mit SHP in Deutschland.Eine papierbasierte Umfrage wurde konzipiert und im April 2020 an alle Universitätsaugenkliniken und weitere potenzielle Zentren versandt. Gefragt wurde nach dem Bestehen einer spezialisierten Sprechstunde, der jährlichen Gesamtzahl der betreuten Patienten, der jährlichen Anzahl von neu diagnostizierten Patienten, den klinischen Kooperationspartnern in Diagnostik und Therapie sowie nach der angewendeten lokalen und systemischen Therapie.Von insgesamt 44 angeschrieben Kliniken erfolgten 28 (64%) vollständige Rückmeldungen. Im Mittel werden in den Kliniken 27 ± 42 (0 – 200) Patienten betreut und jährlich pro Zentrum 3,6 ± 2,2 (0 – 10) neue Fälle diagnostiziert. Dies entspricht einer Gesamtpatientenzahl von 741 Patienten. Lediglich 9 (32%) der antwortenden Kliniken bieten eine spezialisierte SHP-Sprechstunde an. 93% der Zentren kooperieren mit der lokalen Klinik für Dermatologie. 79% führen die serologische und histologische Diagnostik intern durch. Etwa die Hälfte der Zentren (n = 16) wendet ein standardisiertes Therapieschema an. Systemisch werden Glukokortikoide (66,7%) am häufigsten verwendet, gefolgt von Mycophenolatmofetil und Dapson (57,1%), Rituximab (33,3%), Azathioprin und Cyclophosphamid (28,6%) sowie Methotrexat (19,0%). Am seltensten werden i. v. Immunoglobuline eingesetzt (14,3%).Mit dieser Umfrage unter deutschen augenärztlichen Zentren wurden Daten von etwa einem Drittel der geschätzten Gesamtzahl aller in Deutschland an einem SHP erkrankten Menschen erhoben. Dabei handelt es sich vermutlich ausschließlich um Patienten mit mindestens einer okulären Beteiligung. Aktuell wird eine augenärztliche SHP-Registerstudie etabliert, um die Epidemiologie und Versorgungssituation besser zu erfassen und langfristig zu verbessern.

Central subendothelial geographic deposits are formed as a fibrillar layer (FL) in advanced Fuchs endothelial corneal dystrophy (FECD). Previous studies demonstrated a significant decrease in corneal endothelial cell (CEC) density and an increase in focal corneal backscatter in the FL area. The present study investigated the association of the FL with edema formation and its localization. Patients (n = 96) presenting for Descemet membrane endothelial keratoplasty (DMEK) for advanced FECD were included. Slit-lamp biomicroscopy with FECD grading was followed by Scheimpflug imaging with en face backscatter analysis and pachymetric analysis. FL dimensions were measured, and correlation with pachymetric values was performed. An FL was detected in 74% of all eyes (n = 71). Pachymetric values in FL-positive versus FL-negative eyes were for corneal thickness at the apex (ACT) 614 ± 52 µm and 575 ± 46 µm (p = 0.001), for peripheral corneal thickness at 1 mm (PCT1mm) 616 ± 50 µm and 580 ± 44 µm (p = 0.002), for PCT2mm 625 ± 48 µm and 599 ± 41 µm (p = 0.017), for PCT3mm 651 ± 46 µm and 635 ± 40 µm (p = 0.128) and for PCT4mm 695 ± 52 µm and 686 ± 43 µm (p = 0.435), respectively. Correlation analysis indicated a weak correlation for the FL maximum vertical caliper diameter with ACT and PCT1mm values but no further relevant correlations. In FL-positive eyes, increased focal corneal backscatter and increased corneal thickness showed primarily central and inferotemporal localization. In conclusion, Scheimpflug imaging shows an association of the FL with increased corneal thickness in advanced FECD and shows localization of the FL and increased corneal thickness in the central and inferotemporal region. This may provide important information for progression assessment and therapeutic decision making in FECD patients in the future.

Analysis of internet search queries (ISQ) could be useful to study public interest and medical need for corneal, cataract, and refractive surgery. To date, there are preliminary data on seasonal trends in ophthalmic conditions, but only few studies correlate these data with real data from healthcare systems. The aim of this study is to analyze ISQ and correlate it with real healthcare system data. Data were retrieved from the KBV registry of patients who underwent outpatient ophthalmic surgery in Germany from 2017 to 2019 and from Statista GmbH from 2010 to 2020 for corneal refractive surgery. Time Series analysis of ISQ was analyzed from 2004 to 2020 and correlated with healthcare system data using bivariate correlation analysis. ISQ correlated significantly with the incidence of ophthalmic procedures such as corneal transplantations (r = 0.69, p p p

Bei schwerstbeeintrachtigten und vaskularisierten Hochrisikoaugen stellt die Versorgung mittels Boston-Keratoprothese die oftmals letzte Therapieoption dar. Die Transparenz der Optik wird hier nicht durch endotheliale Abstosungsreaktionen beeintrachtigt. In diesem Ubersichtsbeitrag werden relevante Literatur sowie eigene Daten und Erfahrungen zur Versorgung von Hochrisikoaugen mit der Boston-Keratoprothese diskutiert. Die relevanten Komplikationen sowie das postoperative Management werden erortert. In mehr als 60 % der Hochrisikoaugen kann durch eine Keratoprothesenversorgung langfristig ein Visusanstieg erreicht werden. Keratoprothesenretentionswerte schwanken stark, nach 5 Jahren liegen diese im Mittel bei 75 %. Die haufigsten postoperativen Komplikationen umfassen die Ausbildung einer retroprothetischen Membran und das Auftreten von Keratolysen in jeweils bis zu 50 %. Bereits praoperativ leiden mehr als 70 % der Augen an einem (Sekundar‑)Glaukom, sodass ein glaukomchirurgischer Eingriff simultan in mindestens 20 % der Falle erfolgt und im postoperativen Verlauf in bis zu 31 % ein weiterer Eingriff erforderlich wird. Vitreoretinale Komplikationen umfassen insbesondere die sterile Vitritis und die infektiose Endophthalmitis, aber auch die persistierende Bulbushypotonie ist bei einem Drittel der Patienten beschrieben. Die Boston-Keratoprothese kommt bei sehr schlechter Prognose fur einen konventionellen Hornhautersatz infrage. Postoperative Komplikationen sind haufig, sodass dem postoperativen Management eine wichtige Rolle zukommt. Fur vaskularisierte Hochrisikoaugen ist sie jedoch oftmals die einzige verbliebene Option zur Visusrehabilitation.

To develop an artificial intelligence (AI) algorithm enabling corneal surgeons to predict the probability of rebubbling after Descemet membrane endothelial keratoplasty (DMEK) from images obtained using optical coherence tomography (OCT).Anterior segment OCT data of patients undergoing DMEK by 2 different DMEK surgeons (C.C. and B.B.; University of Cologne, Cologne, Germany) were extracted from the prospective Cologne DMEK database. An AI algorithm was trained by using a data set of C.C. to detect graft detachments and predict the probability of a rebubbling. The architecture of the AI model used in this study was called EfficientNet. This algorithm was applied to OCT scans of patients, which were operated by B.B. The transferability of this algorithm was analyzed to predict a rebubbling after DMEK.The algorithm reached an area under the curve of 0.875 (95% confidence interval: 0.880-0.929). The cutoff value based on the Youden index was 0.214, and the sensitivity and specificity for this value were 78.9% (67.6%-87.7%) and 78.6% (69.5%-86.1%).The development of AI algorithms allows good transferability to other surgeons reaching a high accuracy in predicting rebubbling after DMEK based on OCT image data.

Purpose Deep anterior lamellar keratoplasty (DALK) has become a safe and standardized technique for the treatment of corneal diseases. The use of femtosecond lasers for corneal trephination in DALK allows for a precise and controlled corneal trephination very close to Descemet’s membrane (DM) which is important for a successful pneumatic dissection and results in separation of Pre-Descemet’s layer (Dua’s layer, PDL) and/or DM from the stroma. However, even with newer curved contact interfaces the cornea becomes massively warped during trephination causing irregular trephination patterns which results in high postoperative astigmatism. Here we present a novel technique of Femto-DALK using a non-contact liquid interface where the cornea keeps its natural curvature during the complete laser process. Methods Case series of two patients, which underwent femtosecondlaser-assistant deep anterior lamellar keratoplasty by using a non-contact liquid interface. The laser device (Ziemer LDV Z8, Ziemer Ophthalmic Systems AG, Port, Switzerland) was used for trephination of the donor and recipient cornea. In one patient Femto-DALK was combined with femtolaser-assisted cataract surgery (Femto-Phaco). Read-out parameters were the feasibility of the technique and postoperative outcome. Results Trephination was successful in both cases leading to a circular trephination very close to the recipients’ Descemet’s membrane. In both patients a big bubble type 1 was induced successfully. Conclusions Femtosecondlaser-assisted DALK using a liquid interface is a novel procedure representing an alternative to manual DALK or Femto-DALK with a contact interface. Future studies need to evaluate outcomes and complication rates in comparison to manual DALK and microscope-integrated Optical Coherence Tomography-aided DALK.

Zusammenfassung Hintergrund Die Knappheit an Hornhautspendergewebe in der Ukraine erfordert eine möglichst effiziente Nutzung der vorhandenen Transplantate. In diesem Kontext wird in der vorliegenden Arbeit eine Methode beschrieben, bei der mehrere Hornhauttransplantate mit geringerem Durchmesser aus einer einzelnen Spenderhornhaut gewonnen werden, um der Knappheit an Hornhauttransplantaten entgegenzuwirken („multimodales Spendergewebesplitting“). Material und Methoden Die hier beschriebene Studie ist eine retrospektive Kohortenstudie aller durchgeführten Hornhauttransplantationen in der Abteilung für Hornhauterkrankungen des Staatsinstituts „Filatov Institut für Augenkrankheiten und Gewebetherapie der Nationalen Akademie der medizinischen Wissenschaften der Ukraine“, Odessa, Ukraine aus den Jahren 2016 und 2017. Bei dieser Methode der Transplantatpräparation wird das Spendertransplantat entweder über die gesamte Fläche oder lediglich partiell lamelliert, um 1 oder 2 lamelläre bzw. durchgreifende Transplantate zu erhalten. Diese Methode ermöglicht es, nicht nur runde Transplantate auszuschneiden, sondern auch Transplantate, die durch die Form des Hornhautdefekts vorgegeben werden. Ergebnisse Von Januar 2016 bis Dezember 2017 wurden 324 Keratoplastiken unter Verwendung von 270 Transplantaten im o. g. Institut durchgeführt. In 54 Fällen (von denen 34 Notfallsituationen waren) wurde 1 Transplantat für 2 Patienten verwendet. Davon wurden 43 therapeutische Keratoplastiken und 11 periphere lamelläre Keratoplastiken aufgrund rezidivierender Pterygien Grad III – IV durchgeführt. In 2 Fällen wurden 2 Transplantate für einen Patienten aus einer Spenderhornhaut ausgeschnitten. Von 43 Patienten, die eine Keratoplastik mit kurativer Absicht erhielten, verbesserte sich die Sehschärfe in 28 Augen (65,1%) oder blieb in 15 Augen unverändert (34,9%). Die Sehschärfe nach der Operation hing vom Anfangszustand des Auges, der Lokalisation, der Tiefe und der Fläche des Hornhautdefektes ab. Bei peripherer Lokalisation von kornealen Ulzera, selbst beim Vorhandensein einer Perforation der Hornhaut, wurden gute funktionelle Ergebnisse erzielt. Schlussfolgerung Die Gewinnung von 2 oder mehr Transplantaten aus einer einzelnen Spenderhornhaut für verschiedene Keratoplastiktypen verringert den Bedarf an Hornhauttransplantaten und folglich die Kosten für deren Konservierung. Insbesondere in Regionen mit starkem Spendermangel kann dadurch auch mehr Gewebe für Hornhauttransplantationen in Notfallsituationen vorgehalten werden.

PURPOSE To explore the impact of iris color on the outcome of Descemet membrane endothelial keratoplasty (DMEK). METHODS Consecutive cases of Fuchs endothelial dystrophy after DMEK were retrospectively analyzed from the prospective Cologne DMEK database between 2011 and 2017 at the University of Cologne, Germany. Iris pictures were graded by color into blue, green, or brown and compared regarding outcome parameters including best-corrected visual acuity (converted to logarithm of the minimal angle of resolution), central corneal thickness, endothelial cell density (ECD), each at preoperative (baseline) and postoperative 12 months, rebubbling rates, cystoid macular edema (CME), and immune rejections after surgery. RESULTS One thousand one hundred six eyes of 814 patients were included in this study that consisted of 354 blue eyes, 418 green eyes, and 244 brown eyes. There was no significant correlation between iris color and any parameter (best corrected visual acuity; P = 0.064 at preoperatively, P = 0.959 at 12 months) (ECD; P = 0.158 preoperatively, P = 0.859 at 12 months) (central corneal thickness; P = 0.148 preoperatively, P = 0.252 at 12 months). The loss of ECD at 12 months after surgery was 37.2% ± 1.0% in blue eyes, 37.2% ± 0.9% in green eyes, and 37.2% ± 1.2% in brown eyes (P = 0.999). Immune rejections were 1.7%, 2.9%, and 0.8% (P = 0.168) in blue, green, and brown eyes, respectively. Rebubbling rates and CME incidence were similar in each group (P = 0.129, and P = 0.552 respectively). CONCLUSIONS The iris color has no significant impact on the outcome after DMEK. Thus, DMEK can be applied effectively, regardless of the iris color.

Zusammenfassung Hintergrund Die okuläre Beteiligung bei vernarbendem Schleimhautpemphigoid (SHP) ist mit einer Prävalenz von 25 Fällen je 1 Mio. Einwohner und damit ca. 2100 Patienten in ganz Deutschland selten. Die Diagnosestellung kann – besonders in Abwesenheit anderer Beteiligungen – schwierig und die Therapie komplex und langwierig sein. Nicht selten kommen Immunsuppressiva zum Einsatz. Aufgrund der Komplexität von Diagnose und Therapie sind SHP-Patienten meist an entsprechend spezialisierte Zentren angebunden. Ziel dieses Projektes war die Erfassung der aktuellen augenärztlichen Versorgungssituation von Patienten mit SHP in Deutschland. Methoden Eine papierbasierte Umfrage wurde konzipiert und im April 2020 an alle Universitätsaugenkliniken und weitere potenzielle Zentren versandt. Gefragt wurde nach dem Bestehen einer spezialisierten Sprechstunde, der jährlichen Gesamtzahl der betreuten Patienten, der jährlichen Anzahl von neu diagnostizierten Patienten, den klinischen Kooperationspartnern in Diagnostik und Therapie sowie nach der angewendeten lokalen und systemischen Therapie. Ergebnisse Von insgesamt 44 angeschrieben Kliniken erfolgten 28 (64%) vollständige Rückmeldungen. Im Mittel werden in den Kliniken 27 ± 42 (0 – 200) Patienten betreut und jährlich pro Zentrum 3,6 ± 2,2 (0 – 10) neue Fälle diagnostiziert. Dies entspricht einer Gesamtpatientenzahl von 741 Patienten. Lediglich 9 (32%) der antwortenden Kliniken bieten eine spezialisierte SHP-Sprechstunde an. 93% der Zentren kooperieren mit der lokalen Klinik für Dermatologie. 79% führen die serologische und histologische Diagnostik intern durch. Etwa die Hälfte der Zentren (n = 16) wendet ein standardisiertes Therapieschema an. Systemisch werden Glukokortikoide (66,7%) am häufigsten verwendet, gefolgt von Mycophenolatmofetil und Dapson (57,1%), Rituximab (33,3%), Azathioprin und Cyclophosphamid (28,6%) sowie Methotrexat (19,0%). Am seltensten werden i. v. Immunoglobuline eingesetzt (14,3%). Schlussfolgerung Mit dieser Umfrage unter deutschen augenärztlichen Zentren wurden Daten von etwa einem Drittel der geschätzten Gesamtzahl aller in Deutschland an einem SHP erkrankten Menschen erhoben. Dabei handelt es sich vermutlich ausschließlich um Patienten mit mindestens einer okulären Beteiligung. Aktuell wird eine augenärztliche SHP-Registerstudie etabliert, um die Epidemiologie und Versorgungssituation besser zu erfassen und langfristig zu verbessern.

The study aims to compare outcomes after deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in keratoconic eyes with or without previous hydrops.Retrospective analysis of 211 eyes who received PK (group 1, n = 74 [history of hydrops: n = 33]) or DALK (group 2, n = 137 [history of hydrops: n = 9]) from 2012 to 2019 at the Department of Ophthalmology, University of Cologne, Germany. Analysis included best spectacle-corrected visual acuity (BSCVA), complications, immune reactions, graft survival and keratometry, and subgroup analyses for subjects with or without previous hydrops.Follow-up was 34.0 ± 23.6 months in group 1 and 30.7 ± 22.5 months in group 2. No significant difference was found in the course of BSCVA between groups 1 and 2 (p = 0.182) and in postoperative BSCVA between eyes with and without previous hydrops, regardless of the surgical method (p = 0.768). Endothelial immune reactions occurred exclusively in group 1 and did not occur more frequently in eyes with previous hydrops (p = 0.377). A higher risk of complications for eyes with previous hydrops was observed (p = 0.022). There was no difference in astigmatism and maximum keratometry (KThe prognosis for visual outcome after keratoplasty including visual acuity, astigmatism, and K

Objective: To evaluate changes over 3 years in the thickness of inner retinal layers including the peripapillary retinal nerve fiber layer (pRNFL), and combined macular ganglion cell and inner plexiform layers (mGCIPL), in individuals with relapsing-remitting multiple sclerosis (RRMS) versus healthy controls; to determine whether optical coherence tomography (OCT) is sufficiently sensitive and reproducible to detect small degrees of neuroaxonal loss over time that correlate with changes in brain volume and disability progression as measured by the Expanded Disability Status Scale (EDSS). Methods: Individuals with RRMS from 28 centers (n = 333) were matched with 64 healthy participants. OCT scans were performed on Heidelberg Spectralis machines (at baseline; 1 month; 6 months; 6-monthly thereafter). Results: OCT measurements were highly reproducible between baseline and 1 month (intraclass correlation coefficient >0.98). Significant inner retinal layer thinning was observed in individuals with multiple sclerosis (MS) compared with controls regardless of previous MS-associated optic neuritis–group differences (95% CI) over 3 years: pRNFL: -1.86 (-2.54, -1.17) µm; mGCIPL: -2.03 (-2.78, -1.28) µm (both p < 0.0001; effect sizes 0.39 and 0.34). Greater inner retinal layer atrophy was observed in individuals diagnosed with RRMS 5 years (pRNFL: p < 0.05; mGCIPL: p < 0.01). Brain volume decreased by 1.3% in individuals with MS over 3 years compared to 0.5% in control subjects (effect size 0.76). mGCIPL atrophy correlated with brain atrophy (p < 0.0001). There was no correlation of OCT data with disability progression. Interpretation: OCT has potential to estimate rates of neurodegeneration in the retina and brain. The effect size for OCT, smaller than for magnetic resonance imaging based on Heidelberg Spectralis data acquired in this study, was increased in early disease.

Purpose: To evaluate the course of corneal biomechanical properties (corneal hysteresis and corneal resistance factor) after Descemet membrane endothelial keratoplasty (DMEK) in patients with Fuchs endothelial dystrophy (FECD). Methods: In this prospective study, we consecutively included 49 patients with FECD with an indication for DMEK. Central corneal thickness, measured using the Oculus Pentacam, and corneal hysteresis (CH) and corneal resistance factor (CRF), both measured using the Reichert Ocular Response Analyzer, were examined preoperatively, 3 months, and 6 months after DMEK. Results: CH was significantly increased 6 months postoperatively (8.66 +/- 2.50 mm Hg) compared with preoperative baseline (7.43 +/- 1.56 mm Hg). Preoperative CRF (7.89 +/- 1.68 mm Hg) increased significantly 6 months after DMEK (8.49 +/- 1.71 mm Hg). Preoperative central corneal thickness showed a significant decrease from 629 +/- 58 mm to 550 +/- 40 mm after 3 months and 535 +/- 40 mm after 6 months postoperatively. Conclusions: DMEK affects both measured corneal biomechanical properties in patients with FECD: CH and CRF. This has to be taken into account for the accuracy of intraocular pressure measurements.

Die vorliegende Arbeit gibt einen Überblick über die aktuellen therapeutischen Optionen des Keratokonus. Diese unterlagen in den letzten Jahren einem großen Wandel, einige neue therapeutische Möglichkeiten sind ergänzend hinzugekommen. Die Visusverbesserung durch Kontaktlinsen und Hornhauttransplantation wird mittlerweile durch die Anwendung von intracornealen Ringsegmenten ergänzt. Das Crosslinkingverfahren zum Stopp der Progression der Erkrankung wurde mittlerweile auch durch den Gemeinsamen Bundesausschuss im letzten Jahr positiv bewertet. Auch hier gibt es neue Trends, die das Verfahren in Zukunft beschleunigen und schmerzfrei machen könnten. Sehr neu sind die Therapiemöglichkeiten der mini-DMEK und der prädescemetalen Hornhautnähte beim akuten Keratokonus, für den bisher keine effektive operative Therapie zur Verfügung stand. Diese Übersicht gibt einen Einblick in die aktuellen Entwicklungen in Kombination mit modernster intraoperativer Bildgebung zur Therapie des Keratokonus.

Die „Descemet membrane endothelial keratoplasty“ (DMEK) hat sich in Deutschland zur operativen Standardtherapie der Fuchs-Endotheldystrophie entwickelt. Sie kann aber auch bei Endothelerkrankungen in Verbindung mit „komplexen“ Veranderungen des vorderen Augenabschnitts angewendet werden, wie z. B. bei anterioren Synechien oder groseren Irisdefekten, nach Glaukomoperationen, nach Vitrektomie oder nach Trauma. Die Arbeit gibt einen Uberblick uber die Moglichkeiten zur Versorgung mit einer DMEK bei Endotheldekompensation bei komplexer Ausgangssituation. Es erfolgt die Beschreibung von Problemen bei komplexen Ausgangssituationen sowie aktueller Techniken zur Versorgung mit einer DMEK. Fur die Versorgung von Patienten mit komplexer Situation des vorderen Augenabschnitts mit einer DMEK mussen haufig Rekonstruktionen des Iris‑/Linsen-Diaphragmas durchgefuhrt werden. Ein groses Problem stellen sowohl sehr flache als auch sehr tiefe Vorderkammern dar. DMEK-Transplantate von alteren Spendern (>70 Jahre) neigen zu weniger Transplantatrollung und sollten entsprechend bei Patienten mit tiefer Vorderkammer (z. B. nach Vitrektomie) bevorzugt werden. Auch sollte die Transplantatgrose dem Platzangebot angepasst werden, also bei z. B. anterioren Synechien ein kleinerer Transplantatdurchmesser gewahlt werden. Es liegen nur wenige Auswertungen zur DMEK unter komplexen Bedingungen vor. Es zeichnet sich aber ab, dass die Rate an sekundaren Transplantatversagern, der Endothelzellverlust und die Rebubblingrate in dieser sehr heterogenen Gruppe erhoht sind. Weitere Studien sind notwendig, um Risikofaktoren fur einen negativen Verlauf nach DMEK in „komplexen“ Augen zu identifizieren.

The purpose of this study was to describe a simple rescue technique to solve postoperative double anterior chamber refractory to rebubbling in deep anterior lamellar keratoplasty (DALK).This study analyzed consecutive patients who underwent DALK between June 2014 and March 2018 and required a postoperative reattachment of Descemet membrane because of macroperforation-led persistent double chambers. The technique entails placing anchoring sutures to attach Descemet membrane to the donor's posterior stroma. Anchoring sutures were removed within 1 month of surgery. The postoperative best spectacle-corrected visual acuity (BSCVA) [converted to logarithm of the minimum angle of resolution (logMAR) units], endothelial cell density (cells/mm2), graft survival, postoperative complications, and corneal astigmatism (diopters) were evaluated.Five eyes from 5 patients were included in this study [5 women, 63.6 ± 6.0 yrs (32-80 yrs); mean follow-up duration, 72.0 ± 23.3 mo (30-100 mo)] (mean ± SD). The grafts survived successfully in all patients without primary or secondary graft failure. The best spectacle-corrected visual acuity improved from 1.26 ± 0.66 logMAR preoperatively to 0.25 ± 0.15 logMAR postoperatively (n = 5, P = 0.042). The endothelial cell density was 1468 ± 810 cells/mm2 at the last visit.Macroperforation of Descemet membrane during DALK with incomplete removal of the stroma can lead to persistent double anterior chamber. This complication could be solved by the technique devised by this study.

Purpose To compare two surgical treatment options for acute corneal hydrops in keratoconus: Mini-DMEK versus predescemetal sutures. Methods Sixteen patients were treated by either Mini-Descemet membrane endothelial keratoplasty (Mini-DMEK) (n = 7, group 1) or predescemetal sutures (n = 9, group 2) early after onset of acute hydrops. Visual acuity, maximum corneal thickness (SD-OCT) in the affected oedematous area, complications and recurrence rates were retrospectively compared between both groups. Measurements were taken immediately preoperatively as well as 1 day, 1 week and 1 month postoperatively (Table 1). Results Both groups showed reductions in corneal thickness and increased visual acuity shortly after surgery. In group 1 (average age 33 years ± 7 years), the best corrected visual acuity (BCVA) increased from logMAR 1.65 ± 0.7 before Mini-DMEK to logMAR 0.93 ± 0.6 30 days after Mini-DMEK (p = 0.046). During that period, maximum corneal thickness decreased from 1159 ± 338 µm before surgery to 531 ± 75 µm after Mini-DMEK (p = 0.046). Patients from group 2 (average age 34 ± 10 years) had a BCVA of logMAR 1.59 ± 0.8 which increased to logMAR 0.97 ± 0.5 (p = 0.014) 30 days after surgery. At the same time, the preoperative maximum corneal thickness decreased from 1439 ± 272 µm to 476 ± 162 µm (p = 0.014). There was no difference in corneal thickness or BCVA one month after the surgical intervention between both groups (p = 0.394 and p = 0.871). Conclusions Both techniques, Mini-DMEK and predescemetal sutures, are effective in the treatment of an acute hydrops in keratoconus. Mini-DMEK appears to be beneficial in large DM tears.

Purpose To identify mechanical factors, as well as patients’ biometric and surgeons’ experience factors that correlate with the FF incidence in microkeratome (MK)-assisted LASIK and to construct a predictive model based on these parameters. Methods 55,700 consecutive LASIK treatments of 28,506 patients between January 2017 and April 2020 done by 50 surgeons in 10 centers, all with Sub Bowman Keratome (SBK) and 90μ head (OUP) were analyzed retrospectively for the incidence of FF and their correlation to mean keratometry, central corneal thickness, MK ring height and stop, as well as surgeons’ experience. A prediction model was built and tested for sensitivity and specificity. Results The incidence of FF using the SBK MK was 0.276%. Risk factors were low central corneal thickness, very flat (-1) or very thick (+2) ring height, and higher stop values (p Conclusions Free flaps are rarely seen in modern MK LASIK. However, the incidence of this complication using the SBK MK increases using higher stop values, very thick and very thin MK rings, and in eyes with thin corneas.

PURPOSE The purpose of this study was to investigate the impact of transient elevations in postoperative intraocular pressure (IOP) on the clinical outcome of Descemet membrane endothelial keratoplasty (DMEK) surgery in non-glaucoma patients. METHODS Retrospective analysis from a prospective database of eyes without preexisting glaucoma that underwent DMEK with 90% anterior chamber and 20% sulfur hexafluoride endotamponade. Group A included eyes without postoperative IOP increase (IOP

PURPOSE To analyze the effect of anticoagulant therapy (ACT) for systemic diseases on the outcome of Descemet membrane endothelial keratoplasty (DMEK). METHODS Consecutive eyes with Fuchs endothelial dystrophy that underwent DMEK between August 4, 2011, and July 15, 2016, were retrospectively analyzed. Data were obtained from the Cologne DMEK database at the University of Cologne, Germany. Best spectacle-corrected visual acuity (logMAR), endothelial cell density (at baseline and postoperatively up to 12 months), and rebubbling rates were compared between patients receiving ACT (ACT group) and those with no anticoagulant treatment (NCT group). RESULTS In this study, 329 eyes of 329 patients were included (ACT group n = 97, NCT group n = 232; mean age 69.9 ± 9.1 years). Bleeding was more common in the ACT group (P < 0.001). Preoperative best spectacle-corrected visual acuity was 0.59 ± 0.44 and 0.48 ± 0.35 logMAR for the ACT and NCT groups, respectively, which improved to 0.13 ± 0.08 and 0.08 ± 0.16 logMAR, respectively, at 12 months postoperatively. No significant difference in endothelial cell density loss at 12 months was found between the groups (ACT group 36.2% ± 14.7%, NCT group 38.5% ± 15.1%; P = 0.467). Rebubbling rate was 19.6% in the ACT group and 28.9% in the NCT group (P = 0.08). CONCLUSIONS Although ACT increases the risk for preoperative and intraoperative bleeding in DMEK, there seems to be no negative effect on DMEK outcome. Thus, it is not advisable to stop ACT for DMEK surgery.

This study aimed to identify the risk factors for endothelial cell density (ECD) loss after Descemet membrane endothelial keratoplasty (DMEK) and analyse whether donor tissues from cold versus organ culture differ in terms of ECD loss after DMEK. Consecutive DMEK cases from a prospective database for Fuchs’ endothelial corneal dystrophy were retrospectively analysed between 2011 and 2016 at the University of Cologne, and the possible risk factors for ECD loss, including patient-related factors, type of tamponade (air or 20% sulphur hexafluoride gas), type of surgery (triple DMEK or DMEK alone), re-bubbling, immune rejection, and donor-related factors were determined. Eight hundred and forty-one eyes were selected. There was no significant difference in the best-corrected visual acuity (logarithm of the minimal angle of resolution) and corneal thickness (P = 0.540 and P = 0.667) between groups. Immune reactions were more common in cold cultures (P = 0.019), but ECD loss (1 year after DMEK) was greater in organ cultures (38.3 ± 0.8%) than in cold cultures (34.7 ± 1.4%) (P = 0.022). Only re-bubbling was significantly associated with ECD loss (P

Purpose We sought to assess the correlation of corneal endothelial cell (CEC) density to alterations of collagen composition of Descemet membrane (DM) in advanced Fuchs endothelial corneal dystrophy (FECD) and to image such changes by slit-lamp biomicroscopy in vivo. Design Prospective, observational consecutive case series. Methods Fifty eyes (50 subjects) with advanced FECD were enrolled. After slit-lamp biomicroscopy and corneal Scheimpflug imaging, the Descemet endothelium complex (DEC) was retrieved during DM endothelial keratoplasty (DMEK) surgery. The expression of collagens I, III, and IV (COL I, COL III, and COL IV) and corresponding CEC density were analyzed by immunofluorescence flat mount-staining. Presence, diameter and surface area of collagen expression, and CEC density served as the main outcome measures. Results Immunofluorescence staining revealed central coherent collagen positive areas (mean surface area = 10 mm2 ± 6 mm2) corresponding to a fibrillar layer burying the guttae of DM in 84% (42/50) of DECs. CEC density overlying the fibrillar layer compared with the periphery was significantly reduced (−54.8%, P Conclusion A fibrillar layer with a clear geographic pattern marks areas of pronounced loss of CEC density in advanced FECD eyes and may be imaged by slit-lamp biomicroscopy in vivo.

Background/AimsTo analyse graft detachments prior to rebubbling, the influence of rebubbling on the postoperative outcome after Descemet membrane endothelial keratoplasty (DMEK) and the need for rebubbling on the contralateral eye.MethodsIn this retrospective cohort study, out of 1541 DMEKs, optical coherence tomography scans and clinical records of 499 eyes undergoing rebubbling after DMEK at the University Hospital of Cologne, Cologne, Germany, were examined. Main Outcome measures were (a) number, localisation and size of graft detachments; (b) influence of rebubbling/s on postoperative outcome after 12 months; and (c) rebubbling risk of the contralateral eye after DMEK.ResultsMean number of detachment areas was 2.02±0.9. Mean lateral diameter of all detachments was 4534.76±1920.83 μm. Mean axial diameter was 382.53±282.02 μm. Detachments were equally distributed over all regions of the cornea. Best spectacle corrected visual acuity ( BSCVA) after 12 months was 0.197±0.23 logarithm of the minimum angle of resolution, endothelial cell density (ECD) was 1575.21±397.71 cells/mm2 and mean central corneal thickness (CCT) was 566.37±68.11 μm. BSCVA, CCT, ECD or endothelial cell loss of all rebubbled patients were not influenced by the number of rebubblings or the time between DMEK and rebubbling. Of the rebubbled patients, which received a DMEK subsequently on the other eye, 193 (58.8%) also received a rebubbling, which was significantly higher, when compared to the overall rebubbling rate of 32.3% (p=0.000).ConclusionsThe overall number of rebubblings has no influence on the postoperative outcome after DMEK, if a rebubbling becomes necessary. Patients who received a rebubbling on one eye have an elevated risk for a rebubbling on the fellow eye.

PURPOSE Descemet membrane endothelial keratoplasty (DMEK) has developed into a safe procedure for the replacement of diseased corneal endothelium. However, DMEK still results in a significant donor endothelial cell loss. Here, we compare 2 different graft implantation techniques. METHODS Twenty patients undergoing DMEK, where a DMEK injection cartridge was used to flush the graft into the anterior chamber (G-38635 single-use DMEK-Cartridge; Geuder AG, Heidelberg, Germany; group A), were retrospectively compared with 20 patients, where a standard lens injection cartridge (AT.Smart Cartridge; Carl Zeiss Meditec AG, Jena, Germany; group B) was used to push the graft with a plunger. Outcome parameters were intraoperative orientation of the graft, insertion-to-attachment time, rebubbling rates, and postoperative best spectacle-corrected visual acuity, endothelial cell count, and central corneal thickness after 12 months. The surfaces of both cartridges were evaluated by scanning electron microscopy. RESULTS In group A, the insertion-to-attachment time was significantly higher (P = 0.003). Initially, the graft was oriented correctly in 40% of the patients in group A compared with 90% in group B (P = 0.001). No differences were obtained between both groups regarding central corneal thickness, endothelial cell count or best spectacle-corrected visual acuity, and rebubbling rates after 12 months. Scanning electron microscopy analysis demonstrated a rougher and sharper surface of the shooter of group B. CONCLUSIONS This study shows significant differences between both insertion techniques regarding correct graft orientation directly after graft implantation leading to prolonged insertion-to-attachment time when the graft is flushed instead of pushed into the anterior chamber.

Purpose To assess the long-term outcome of Descemet membrane endothelial keratoplasty (DMEK) following failed penetrating keratoplasty (PK). Methods Retrospective review of 1840 consecutive DMEK surgeries from the prospective Cologne DMEK database performed between 07/2011 and 08/2017 at the Department of Ophthalmology, University of Cologne. Results Fifty-two eyes received a DMEK surgery after failed PK. Main indications for initial PK were Fuchs endothelial corneal dystrophy (23.1%), keratoconus and herpetic keratitis (each 15.4%). Best-corrected visual acuity (BCVA) at 3, 6 and 12 months was 0.72 ± 0.39 (n = 33), 0.56 ± 0.36 (n = 32) and 0.38 ± 0.28 (n = 23), respectively. Two- and 3-year BCVA was 0.37 ± 0.21 (n = 21) and 0.32 ± 0.18 (n = 10). Mean improvement in visual outcome in logMAR lines was +4.3 ± 3.4 at 6 months, +5.0 ± 3.6 at 12 months, +6.0 ± 2.3 at 24 months and +5.4 ± 2.7 at 36 months, respectively. 59.6% received at least one rebubbling and 40.4% did not necessitate a rebubbling. Endothelial cell density (ECD)-decrease at 6 months was 36% (n = 17), 37% at 12 months (n = 17), 40% at 2 years (n = 8) and 32% at 3 years (n = 2). 34.6% of transplants needed a regraft. Conclusion Descemet membrane endothelial keratoplasty (DMEK) is a feasible treatment option after failed PK having a relatively good long-term outcome.

Vorgestellt wird das therapeutische Prinzip der Narkoseuntersuchungen von Kindern in Vollnarkose mithilfe der mikroskopintegrierten optischen Koharenztomographie (MI-OCT). Ziel ist die Evaluierung neuartiger Indikationen und Limitationen der MI-OCT mit dem Ziel, die ophthalmologischen Untersuchungen unter Vollnarkose bei Neugeborenen und Kleinkindern zu verbessern. Grundlage war eine Literaturubersicht aus google.scholar.com und PubMed. Wir erganzten eigene Daten einer prospektiven Studie am Zentrum fur Augenheilkunde der Uniklinik Koln. Es wurden 14 Kinder mit Anomalien des vorderen und hinteren Augenabschnittes eingeschlossen, bei denen eine Narkoseuntersuchung unter Zuhilfenahme eines kommerziell erhaltlichen MI-OCT-Gerates durchgefuhrt wurde. Analysiert wurden die generelle Durchfuhrbarkeit der MI-OCT bei der ophthalmologischen Untersuchung von Kindern unter Vollnarkose fur den vorderen und hinteren Augenabschnitt und der Benefit fur die jeweilige Indikationsstellung sowie die intraoperativen Befunde. Die MI-OCT bereicherte signifikant die Narkoseuntersuchungen von Kindern und lieferte zusatzliche Informationen, die mit dem alleinigen Operationsmikroskop nicht zuganglich waren. Gerade in Situationen, bei denen der Einblick in die Vorderkammer limitiert war, ermoglichte die MI-OCT die Schatzung von Distanzen wie der Hornhautdicke. Daruber hinaus wurden 12/14 therapeutische Entscheidungen intraoperativ beeinflusst. Zudem ermoglichte die MI-OCT die Untersuchung der Nervenfaserschichtdicke der Sehnervenpapille und der Retina. Die hier prasentierten Daten verdeutlichen den Benefit der mikroskopintegrierten intraoperativen OCT bei ophthalmologischen Untersuchungen von Kindern unter Vollnarkose, insbesondere auch bei Kindern mit Hornhauttrubungen, falls eine Untersuchung unter Vollnarkose notwendig wird.

Bei der „Descemet membrane endothelial keratoplasty“ (DMEK) werden selektiv erkranktes Hornhautendothel und Descemet-Membran entfernt und durch gesundes Spendergewebe ersetzt. Die DMEK stellt heute den Goldstandard zur Therapie der kornealen endothelialen Dysfunktion dar. Im vorliegenden Beitrag wird die Operationstechnik der DMEK anhand eines Videos dargestellt, und daruber hinaus werden Operationsindikationen, Patientenaufklarung, Anasthesie und Lagerung, postoperative Behandlung sowie mogliche Komplikationen und deren Management erlautert. Die DMEK kann im breiten Spektrum zur Therapie der kornealen endothelialen Dysfunktion angewendet werden. Die Grundlage fur die hervorragenden Ergebnisse des Operationsverfahrens sind neben der operativen Umsetzung auch sorgfaltige Spender-Patienten-Allokation, grundliche Voruntersuchung und Nachsorge der Patienten und Erfahrung des Operateurs. Die DMEK ist ein sicheres und effektives Verfahren zur Therapie der kornealen endothelialen Dysfunktion. Ein standardisiertes und individualisiertes Vorgehen ermoglicht im Vergleich mit allen bisherigen Transplantationsverfahren optimalste Ergebnisse.

Purpose To assess the evolution of clinical outcomes of more than 1300 Descemet membrane endothelial keratoplasties (DMEKs) alone or in combination with cataract surgery (triple DMEK) throughout a 5-year period at a single center, performed by 2 already experienced DMEK surgeons. Design Retrospective trend study. Methods Review of charts between July 2011 and July 2016 at the Department of Ophthalmology, University of Cologne, Germany. Results A total of 1340 out of 1340 eyes with sufficient information were included. Six-month and 12-month best spectacle-corrected visual acuity (logMAR) had already reached high levels for the surgeries performed in 2011 (0.10 ± 0.06 and 0.09 ± 0.07, respectively) and did not further improve in later years ( P = .272). Likewise, endothelial cell loss (ECL) and central corneal thickness (CCT) reached comparable levels independently of the year of surgery (average 12-month ECL was 38% ± 15% and average 6-month CCT decrease was 19% ± 11%). However, there was a decrease in the rebubbling rate, from 68% in 2011, 67% in 2012, and 70% in 2013 to 53% in 2014, 29% in 2015, and 16% in 2016, which was associated with the introduction of 20% sulfur hexafluoride (SF 6 ) instead of room air for anterior chamber tamponade in 2015 (n = 986; P P Conclusions After an initial learning curve in DMEK surgery, results of visual acuity and ECL do not seem to further improve. However, the complication rate continuously declines, at least over the subsequent 5-year period analyzed herein.

Zusammenfassung Hintergrund Die chirurgische Behandlung von Hornhautdystrophien entwickelt sich mit zunehmender Anwendung von lamellären Techniken der Hornhauttransplantation rasant weiter. War vor einigen Jahren noch die penetrierende Keratoplastik der Goldstandard zur Therapie einer Vielzahl von Dystrophien, so können heutzutage selektiv die betroffenen Schichten der Hornhaut ersetzt oder mittels Lasertechnik abladiert werden. Einen besonderen Stellenwert nimmt für diese Verfahren die optische Kohärenztomografie ein, die neuerdings auch in Operationsmikroskope integriert sein kann (MI-OCT). Methoden Literaturübersicht aus PubMed und Google.scholar.de ergänzt mit eigenen Bildgebungsdaten. Ergebnisse Die MI-OCT ermöglicht das intraoperative Echtzeit-Monitoring unterschiedlicher ophthalmochirurgischer Prozeduren wie der tiefen, anterioren lamellären Keratoplastik, der Descemet-Membran-Endothel-Keratoplastik (DMEK), aber auch minimalinvasiver Verfahren wie der phototherapeutischen Keratektomie (PTK). Darüber hinaus ermöglicht sie eine Evaluation der Hornhaut wie auch der Vorderkammer, insbesondere in Situationen einer getrübten Hornhaut. Schlussfolgerung Die mikroskopintegrierte intraoperative optische Kohärenztomografie (MI-OCT) stellt eine sinnvolle Ergänzung zum normalen Operationsmikroskop dar. Sie ist insbesondere bei bereits stark getrübten Hornhäuten dem alleinigen Operationsmikroskop überlegen und stellt gerade bei neuartigen lamellären Transplantationsverfahren eine sinnvolle Ergänzung dar. Randomisierte prospektive Studien sind nötig, um die erhöhte Sicherheit und gesteigerte Effektivität durch den Einsatz der MI-OCT bei verschiedenen Indikationen zu belegen.

Purpose The change from air to 20% sulfur hexafluoride (SF6) as anterior chamber tamponade for Descemet membrane endothelial keratoplasty (DMEK) significantly reduced the rebubbling rate. Nonetheless, underlying mechanisms are not completely understood. In this study, we investigate the morphology of graft detachments after DMEK depending on the tamponade and its influence on postoperative rebubbling. Methods In this retrospective analysis of prospective data of 204 consecutive patients who underwent DMEK with 100% air, or 20% SF6, we compared the SF6 group with the air group regarding the number, lateral and axial diameter and localization of detachments, visual acuity (BSCVA), and incidence of rebubbling after 1 week (T1), after 1 (T2), 3 (T3), 6 (T4), and 12 (T5) months postoperatively. Results The air group showed more detachments at all time points. Detachments in this group were of a larger axial diameter at T1, T4, and T5 and of a larger lateral diameter at T1, T3, T4, and T5 compared with the SF6 group. Patients receiving SF6 needed fewer rebubblings at T1 compared with patients receiving air (12.1% vs. 29.1%, P = 0.003), but not at T2 (15.1% vs. 19.1%, P = 0.56). There was no difference in postoperative BSCVA between the groups. Conclusions Early graft attachment after DMEK, which is improved by the use of SF6 as anterior chamber tamponade, is important for the overall rebubbling rate and improves wound-healing mechanisms between the graft and recipient cornea. Faster resolving air tamponade is associated with extended detachments especially inferiorly and mid-peripherally, but has no negative effect on the long-term BSCVA.

Excimer laser phototherapeutic keratectomy (PTK) is a safe treatment for superficial corneal opacities, e.g., in corneal dystrophies or degenerations. Nevertheless, no standardized treatment protocols are available and intraoperative monitoring was not possible, so far. Here we evaluate the potential benefits of the intraoperative assessment by microscope-integrated intraoperative optical coherence tomography (MI-OCT) of corneal optical properties during PTK. Retrospective study of eight patients (one male, seven females; age range, 43–80 years, mean = 66.1 years) using an 840-nm microscope-integrated spectral-domain OCT (iOCT; OptoMedical Technologies, Luebeck, Germany adapted to HS Hi-R Neo 900A, Haag Streit Surgical, Wedel, Germany). Images were acquired before and after corneal abrasion and after PTK. For PTK, a SCHWIND Amaris 750S excimer laser (SCHWIND eye-tech-solutions GmbH und KO. KG) was used. Parameters assessed were the central corneal thickness (CCT), changes in central depth-dependent corneal tissue intensity (TI), and corneal surface roughness (SR) in cross-sectional images of the cornea. Intraoperative monitoring using microscope-integrated OCT was possible in all patients at all time points. TI of the anterior corneal stroma decreased significantly (p = 0.037) after PTK (T1 = 15.1 ± 3.6, T2 = 15.0 ± 3.84, T3 = 13.7 ± 3.38), but not after corneal abrasion alone, indicating increased transparency caused by excimer laser PTK. CCT was significantly lower after corneal abrasion (p = 0.017), but not after PTK (T1 = 630.4 ± 70 μm, T2 = 544.1 ± 59.4 μm, T3 = 558.3 ± 52.5 μm. SR significantly decreased (p = 0.043) after PTK (T1 = 614.4 ± 37.5 pixels, T2 = 634.4 ± 35.6 pixels, T3 = 611.0 ± 40.3 pixels). Intraoperative OCT allows real-time imaging during PTK and the assessment of corneal optical transparency and its surface roughness. It has to be clarified in larger studies if these parameters correlate with later postoperative visual outcomes.

There is a high demand for developing methods to produce more native-like 3D corneal structures. In the present study, we produced 3D cornea-mimicking tissues using human stem cells and laser-assisted bioprinting (LaBP). Human embryonic stem cell derived limbal epithelial stem cells (hESC-LESC) were used as a cell source for printing epithelium-mimicking structures, whereas human adipose tissue derived stem cells (hASCs) were used for constructing layered stroma-mimicking structures. The development and optimization of functional bioinks was a crucial step towards successful bioprinting of 3D corneal structures. Recombinant human laminin and human sourced collagen I served as the bases for the functional bioinks. We used two previously established LaBP setups based on laser induced forward transfer, with different laser wavelengths and appropriate absorption layers. We bioprinted three types of corneal structures: stratified corneal epithelium using hESC-LESCs, lamellar corneal stroma using alternating acellular layers of bioink and layers with hASCs, and finally structures with both a stromal and epithelial part. The printed constructs were evaluated for their microstructure, cell viability and proliferation, and key protein expression (Ki67, p63α, p40, CK3, CK15, collagen type I, VWF). The 3D printed stromal constructs were also implanted into porcine corneal organ cultures. Both cell types maintained good viability after printing. Laser-printed hESC-LESCs showed epithelial cell morphology, expression of Ki67 proliferation marker and co-expression of corneal progenitor markers p63α and p40. Importantly, the printed hESC-LESCs formed a stratified epithelium with apical expression of CK3 and basal expression of the progenitor markers. The structure of the 3D bioprinted stroma demonstrated that the hASCs had organized horizontally as in the native corneal stroma and showed positive labeling for collagen I. After 7 days in porcine organ cultures, the 3D bioprinted stromal structures attached to the host tissue with signs of hASCs migration from the printed structure. This is the first study to demonstrate the feasibility of 3D LaBP for corneal applications using human stem cells and successful fabrication of layered 3D bioprinted tissues mimicking the structure of the native corneal tissue.

Spaceflight-associated neuro-ocular syndrome (SANS) involves unilateral or bilateral optic disc edema, widening of the optic nerve sheath, and posterior globe flattening. Owing to posterior globe flattening, it is hypothesized that microgravity causes a disproportionate change in intracranial pressure (ICP) relative to intraocular pressure. Countermeasures capable of reducing ICP include thigh cuffs and breathing against inspiratory resistance. Owing to the coupling of central venous pressure (CVP) and intracranial pressure, we hypothesized that both ICP and CVP will be reduced during both countermeasures. In four male participants (32 ± 13 yr) who were previously implanted with Ommaya reservoirs for treatment of unrelated clinical conditions, ICP was measured invasively through these ports. Subjects were healthy at the time of testing. CVP was measured invasively by a peripherally inserted central catheter. Participants breathed through an impedance threshold device (ITD, −7 cmH2O) to generate negative intrathoracic pressure for 5 min, and subsequently, wore bilateral thigh cuffs inflated to 30 mmHg for 2 min. Breathing through an ITD reduced both CVP (6 ± 2 vs. 3 ± 1 mmHg; P = 0.02) and ICP (16 ± 3 vs. 12 ± 1 mmHg; P = 0.04) compared to baseline, a result that was not observed during the free breathing condition (CVP, 6 ± 2 vs. 6 ± 2 mmHg, P = 0.87; ICP, 15 ± 3 vs. 15 ± 4 mmHg, P = 0.68). Inflation of the thigh cuffs to 30 mmHg caused no meaningful reduction in CVP in all four individuals (5 ± 4 vs. 5 ± 4 mmHg; P = 0.1), coincident with minimal reduction in ICP (15 ± 3 vs. 14 ± 4 mmHg; P =0.13). The application of inspiratory resistance breathing resulted in reductions in both ICP and CVP, likely due to intrathoracic unloading.

Lymphangiogenesis is essential for fluid homeostasis in vascularized tissues. In the normally avascular cornea, however, pathological lymphangiogenesis mediates diseases like corneal transplant rejection, dry eye disease, and allergy. So far, a physiological role for lymphangiogenesis in a primarily avascular site such as the cornea has not been described. Using a mouse model of perforating corneal injury that causes acute and severe fluid accumulation in the cornea, we show that lymphatics transiently and selectively invade the cornea and regulate the resolution of corneal edema. Pharmacological blockade of lymphangiogenesis via VEGFR-3 inhibition results in increased corneal thickness due to delayed drainage of corneal edema and a trend towards prolonged corneal opacification. Notably, lymphatics are also detectable in the cornea of a patient with acute edema due to spontaneous Descemet´s (basement) membrane rupture in keratoconus, mimicking this animal model and highlighting the clinical relevance of lymphangiogenesis in corneal fluid homeostasis. Together, our findings provide evidence that lymphangiogenesis plays an unexpectedly beneficial role in the regulation of corneal edema and transparency. This might open new treatment options in blinding diseases associated with corneal edema and transparency loss. Furthermore, we demonstrate for the first time that physiological lymphangiogenesis also occurs in primarily avascular sites.