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Purpose: Descemet membrane endothelial keratoplasty (DMEK) accounts for >50% of all corneal transplants in Germany. So far, no data from such a large multicenter study have been published., Methods: This retrospective study included 3200 DMEKs at seven departments performed for Fuchs endothelial corneal dystrophy (FECD) or bullous keratopathy (BK). We evaluated best corrected visual acuity (BCVA, logMAR), endothelial cell density (ECD, cells/mm 2 ), minimal corneal thickness (CT, μm), rebubbling-, primary transplant failure- and immune reaction-rate. Changes over time were evaluated by linear mixed models for repeated measures and correlation with case number by center by weighted linear regression., Results: For patients without vision-limiting comorbidities (74% of all analysed eyes, n = 2270), mean BCVA improved from 0.6 ± 0.4 logMAR to 0.2 ± 0.2 logMAR 6 months (p < 0.001, n = 1441) and 0.1 ± 0.2 logMAR 12 months (p = 0.001, n = 1402) postoperatively. BK- had a worse BCVA compared to FECD-patients (0.3 ± 0.5 vs. 0.1 ± 0.2 logMAR [p < 0.001] at 1 year). ECD declined from 2465 ± 259 cells/mm 2 (n = 2876 preoperatively) to 1587 ± 433 cells/mm 2 after 12 months (p < 0.001, n = 1237). Mean rebubbling rate was 0.4 ± 0.7/eye. 784 eyes (25%) received at least one rebubbling. More rebubblings correlated with a lower ECD, a worse BCVA, a higher CT, and higher transplant failure and rejection rates (p < 0.001, p = 0.013 for BCVA at 12 months). A single rebubbling did not influence the BCVA (p = 0.785). Graft failure rate was 3% (n = 67), rejection rate 1.5% (n = 48)., Conclusion: Descemet membrane endothelial keratoplasty increases visual acuity with low transplant failure- and rejection-rates. FECD has a better outcome than BK. Since a quarter of all patients need a rebubbling, this should be included in the informed consent. Remarkably, one rebubbling has no influence on the outcome., (© 2022 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht.

Purpose: Evaluating the learning curve of individual surgeons for Descemet Membrane Endothelial Keratoplasty (DMEK) and Triple-DMEK and assessing outcome with experience., Methods: The first 41 and the last 41 surgeries of each of the four surgeons were retrospectively included. Surgery duration and graft preparation time were recorded. Corrected distance visual acuity (CDVA, logMAR) and central corneal thickness (CCT, µm) were collected preoperatively after 6 and 12 months, as well as postoperative complications, e.g., re-bubbling or repeat penetrating keratoplasty., Results: Surgical duration for Triple-DMEK and DMEK decreased significantly by 21 min and 14 min between the two periods ( p < 0.001; p < 0.001). Graft preparation time decreased significantly from 13.3 ± 5.2 min (95%CI 12.8-14.3) in period 1 to 10.7 ± 4.8 min (95%CI 10.2-11.4) in period 2 ( p = 0.002). The postoperative changes in CDVA and CCT over both periods were not significant ( p = 0.900; p = 0.263). The re-bubbling rate decreased significantly from 51.2% in period 1 to 26.2% in period 2 ( p < 0.001). The repeat penetrating keratoplasty (PKP) was 7.3% in period 1 and 3.7% in period 2 ( p = 0.146). Re-DMEK was necessary in 6.1% in period 1 and 4.9% in period 2 ( p = 0.535). Several parameters showed significant differences between the surgeons in both periods (surgical duration: period 1: p < 0.001, period 2 p < 0.001; graft preparation: period 1: p < 0.001, period 2 p < 0.001)., Conclusion: Significant decrease in surgery duration, graft preparation time, and the re-bubbling rate can be attributed to gained individual experience.

Background: The aim of the study was to evaluate the impact of simultaneous amniotic membrane transplantation (AMT), status of the cornea (own cornea vs. graft) and underlying disease on the success and recurrence rates of autologous serum (AS) in therapy-resistant epithelial defects., Patients and Methods: Between 2007 and 2019, 990 treatments with AS in 703 eyes of 645 patients were retrospectively examined. The presence of erosion or ulcer, use of AMT, status of the cornea and the underlying disease were recorded. Epithelial closure rate within 4 weeks and the recurrence rate after epithelial closure were main outcome measures. The median observation period was 50 months., Results: Epithelial closure was seen in 73.6% and recurrence in 27.4%. AMT was used significantly more often for ulcers (p < 0.001) and recurrences (p = 0.048). Without AMT, there was a significantly higher epithelial closure rate (p < 0.001) and faster healing tendency (p < 0.001). There was no difference between own corneas and grafts with respect to epithelial closure rate (p = 0.47). On the grafts there was a significantly higher recurrence rate (p = 0.004) and faster recurrence (p = 0.03), especially ≤6 months after epithelial closure. The underlying diseases showed a significant difference in epithelial closure rate (p = 0.02) and recurrence rate (p < 0.001) with highest success in corneal dystrophies and lowest in congenital aniridia., Conclusion: AS is an effective therapeutic option for therapy-resistant epithelial defects. There was a high success rate for the grafts but with a higher tendency to develop recurrences. In cases of simultaneous AMT, a reduced success rate can be expected, due to the higher complexity of the given situation. AS can be used successfully in various underlying diseases, with limitations in case of congenital aniridia., (© 2022. The Author(s).)

Competing Interests: The authors declare that they have no conflict of interest.

Purpose: The aim of this study was to analyze the prevalence and severity of corneal guttata (CG) in grafts after penetrating keratoplasty (PKP) and to determine its clinical significance., Methods: This retrospective study included 1758 PKP performed in 1522 patients. In total, 6662 postoperative endothelial images revealed the prevalence and severity of CG (divided into categories G0 without CG and G1-G3 with increasing severity). Origin of the graft, postoperative corneal thickness, visual acuity, pleomorphism, polymegethism, and endothelial cell density (ECD) were analyzed., Results: CG was detected in 14.9% of the grafts within 9 months after PKP, most of them were low-grade G1 (13.6%). Grafts from Homburg/Saar showed significantly less CG cases compared with other eye banks ( P = 0.034). The mean corrected distance visual acuity (logMAR) did not differ between G1 (0.45 ± 0.31) and G0 (0.46 ± 0.31). The mean ECD was lower in G1 compared with G0 ( P < 0.001). The mean corneal thickness was higher in G3 (597 ± 101 μm) compared with G0 (541 ± 65 μm) ( P < 0.001). Pleomorphism and polymegethism were correlated with CG ( P < 0.001). A progression of CG severity was detected in 13.5% of the cases during a follow-up time of 25.0 ± 19.9 months., Conclusions: Our study suggested that CG are transplanted in 14.9% of PKP, most of which are low-grade CG not affecting the visual acuity but already leading to an increase in corneal thickness, loss of ECD, and alteration of endothelial cell morphology. In 13.5% of the cases, a progression was demonstrated in the postoperative course., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To highlight the typical histological and ultrastructural features of severe infectious crystalline keratopathy (ICK) in a corneal graft, which required excimer laser-assisted repeat penetrating keratoplasty (PKP) and to present the challenging treatment conditions associated with ICK., Methods: An 85-year-old female patient underwent PKP for secondary graft failure after Descemet membrane endothelial keratoplasty (DMEK) for Fuchs' endothelial corneal dystrophy in the left eye. One year later, white branched opacities were observed in the superficial corneal stroma of the graft without surrounding inflammation in the left eye. The patient underwent excimer laser-assisted repeat PKP (8.0/8.1 mm) in the left eye after prolonged refractory topical anti-infectious treatment for 1 month. The corneal explant was further examined by light and transmission electron microscopy (TEM)., Results: The light microscopic examination of the corneal explant demonstrated aggregates of coccoid bacteria in the superficial and mid-stromal region that were positive for periodic acid-Schiff (PAS) and Gram stain. The bacterial aggregates extended into the interlamellar spaces, showed a spindle-shaped appearance, and were not surrounded by an inflammatory cellular reaction. TEM demonstrated lamellae separation within the anterior corneal stroma with spindle-shaped aggregates of bacteria, which were embedded in an extracellular amorphous matrix with incipient calcification, being consistent with a biofilm. No inflammatory cellular reaction was evident by TEM. At discharge from hospital, the corrected visual acuity was 20/80 in the left eye., Conclusion: ICK is often challenging due to the difficult diagnosis and treatment conditions. The refractory courses are mainly attributed to a biofilm formation, which inhibits effective topical anti-infectious treatment. In such cases, (repeat) PKP may be necessary to completely remove the pathology, prevent recurrences, and improve vision., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

To evaluate the reliability and efficiency of sterile pachymetric measurements of donor corneas based on tomographic data using two different methods: a "manual" and a "(semi-)automated" method. Twenty-five (25) donor corneas (50%) stored in MI and 25 (50%) in MII were imaged 5 times consecutively using an anterior segment OCT (AS-OCT). The central corneal thickness (CCT) was measured both with the manual measurement tool of the AS-OCT (= CCTm) and with a MATLAB self-programmed software allowing (semi-)automated analysis (= CCTa). We analyzed the reliability of CCTm and CCTa using Cronbach´s alpha (α) and Wilcoxon signed-Rank Test. Concerning CCTm, 68 measurements (54.4%) in MI and 46 (36.8%) in MII presented distortions in the imaged 3D-volumes and were discarded. Concerning CCTa, 5 (4%) in MI and 1 (0.8%) in MII were not analyzable. The mean (± SD) CCTm was 1129 ± 6.8 in MI and 820 ± 5.1 µm in MII. The mean CCTa was 1149 ± 2.7 and 811 ± 2.4 µm, respectively. Both methods showed a high reliability with a Cronbach´s α for CCTm of 1.0 (MI/MII) and for CCTa of 0.99 (MI) and 1.0 (MII). Nevertheless, the mean SD of the 5 measurements was significantly higher for CCTm compared to CCTa in MI (p = 0.03), but not in MII (p = 0.92). Sterile donor tomography proves to be highly reliable for assessment of CCT with both methods. However, due to frequent distortions regarding the manual method, the (semi-)automated method is more efficient and should be preferred., (© 2021. The Author(s).)

Competing Interests: The authors declare that they have no conflict of interest.

Purpose: The aim of this study was to determine the prevalence and severity of cornea guttata (CG) in grafts after Descemet membrane endothelial keratoplasty (DMEK) and to investigate its impact on various clinical parameters during follow-up., Methods: This retrospective study included 664 operations (DMEK and triple-DMEK) on 466 patients. The prevalence and progression of CG after the operation were examined using endothelial specular microscopy images. The severity grade of CG was classified into four grades: G0 without CG, G1 - G3 with increasing severity of CG. Clinical parameters such as central corneal thickness (CCT), visual acuity (VA), endothelial cell density (ECD), pleomorphism and polymegalism were examined during a postoperative follow-up time of 19.6 ± 15.8 months., Results: Cornea guttata (CG) appeared postoperatively in 124 (18.7%) eyes. 112 (16.9%) could be classified as G1, 9 (1.4%) as G2 and only 3 (0.5%) as G3. The examination of clinical parameters showed significant differences between healthy and low-grade CG (G0/G1) and high-grade CG (G2/G3). A significant deterioration was found in the corrected distance visual acuity (CDVA) (p = 0.02). CCT showed an increase between G0 (534 ± 58 μm) and G2 (549 ± 71 μm)/G3 (558 ± 56 μm) with a p-value of 0.02. Additionally, a significant increase in pleomorphism (p = 0.003) and polymegalism (p = 0.04) was detected., Conclusion: Cornea guttata (CG) prevalence after DMEK and triple-DMEK was found to be 18.7%, although most of these cases were classified as low-grade CG and showed no clinical significance. Around 1.9% were classified as high-grade CG and significantly affected several clinical parameters during the follow-up., (© 2022 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

Purpose: To report the indications and outcomes of penetrating keratoplasties with a graft diameter > 8.5 mm in severe corneal diseases at the Department of Ophthalmology at Saarland University Medical Centre., Study Design: Retrospective (6 years), descriptive, and observational., Methods: Thirty-five large-diameter penetrating keratoplasties (LDPKPs) in 27 patients (mean age, 62 ± 22 years) were performed from March 2010 to December 2016. The indication for surgery, number of previous corneal transplantations, best-corrected visual acuity (BCVA) before surgery, intraocular pressure, graft status, and BCVA at last follow-up were recorded., Results: Infectious keratitis represented 83% of the indications (of those, 45% fungal). The mean corneal graft diameter was 10.8 ± 1.7 (min 8.75, max 15.0) mm. Twenty-three eyes (65% absolute) had at least one previous penetrating keratoplasty (mean graft size, 9.2 ± 1.6 mm). The mean pre-surgery BCVA was 1.96 ± 0.23 logMAR. With a mean follow-up period of 20.2 ± 13.4 months, the mean BCVA was 1.57 ± 0.57 logMAR at last follow-up. Overall, 12 grafts (35%) remained clear until the last follow-up, and in 23 grafts (65%), the primary disease recurred, or corneal decompensation developed. Up to the last follow-up, 6 eyes (17%) had to be enucleated., Conclusions: In complex cases of infectious keratitis requiring a LDPKP to remove the complete pathology and preserve eye integrity, the visual outcomes are generally expected to be poor, not only because of the well-known risks of LDPKP but also because of the consequences of the infectious disease itself. This knowledge is important for adequate counselling of the patient preoperatively., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Purpose: To evaluate the reliability and efficiency of sterile corneal thickness measurements of donor corneas stored in a plastic culture flask filled with organ culture medium I (MI) or II (MII) based on tomographic data using two different software: the built-in software of the anterior segment OCT (AS-OCT) and a MATLAB self-programmed software., Methods: Twenty-five (25) donor corneas (50%) stored in MI and 25 (50%) in MII were imaged 5 times consecutively using an AS-OCT. The central corneal thickness (CCT) was measured both with the manual measurement tool of the AS-OCT (=CCTm) and with a MATLAB self-programmed software allowing (semi-)automated analysis (=CCTa). We analyzed the reliability of CCTm and CCTa using Cronbach´s alpha (α) and Wilcoxon signed-rank test., Results: Concerning CCTm, 68 measurements (54.4%) in MI and 46 (36.8%) in MII presented distortions in the imaged 3D-volumes and were discarded. Concerning CCTa, 5 (4%) in MI and 1 (0.8%) in MII were not analyzable. The mean (± SD) CCTm was 1129 ± 6.8 in MI and 820 ± 5.1 µm in MII. The mean CCTa was 1149 ± 2.7 and 811 ± 2.4 µm, respectively. Both methods showed a high reliability with a Cronbach´s α for CCTm of 1.0 (MI/MII) and for CCTa of 0.99 (MI) and 1.0 (MII). Nevertheless, the mean SD of the 5 measurements was significantly higher for CCTm compared to CCTa in MI (p = 0.03), but not in MII (p = 0.92)., Conclusions: Sterile donor tomography proves to be highly reliable for assessment of CCT with both methods. However, due to frequent distortions regarding the manual method, the (semi-)automated method seems to be more efficient and should be preferred., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: This study evaluated the biomechanical E-staging in progressive keratoconus (KC) corneas before and after epithelium-off accelerated corneal cross-linking (CXL, 9 mW/cm2, 10 min, 5.4 J/cm2)., Design: German university-based retrospective longitudinal cohort study., Methods: The biomechanical E-staging for ectatic corneal diseases was applied retrospectively on 49 progressive KC corneas of 41 patients who underwent CXL. Main outcome parameters included the Corvis Biomechanical Factor (CBiF, the linearized Corvis Biomechanical Index), the biomechanical E-staging (E1 to E4 result of dividing the CBiF value range into 5 groups), maximal anterior keratometry (Kmax), anterior radius of curvature (ARC), and thinnest corneal thickness (TCT). They were evaluated at 2.1±2.0 months preoperatively (n=49 corneas, 41 patients) and postoperatively after 5.4±1.4, 11.3±1.8, and 23.4±1.6 months., Results: The CBiF decreased (5.1±0.5 | 5.0±0.5, P=0.0338) and the E-staging increased significantly (2.4±0.9 | 2.6±0.8, P=0.0035) from preoperatively to the first postoperative follow-up. The difference was not significant after 11 months and there were same values after 23 months. Kmax, ARC, and TCT slightly decreased (Kmax: 56.9±6.3, 54.3±5.1, 56.2±6.6, 54.0±5.2; ARC: 49.8±3.5, 48.9±3.2, 50.8±5.6, 49.0±3.7; TCT: 470±34, 454±36, 459±35, 466±39; preoperatively and 5, 11, and 23 months postoperatively). A postoperatively decreased TCT was associated with an increased E-stage, whereas an equal or increased TCT measurement after CXL was associated with equal or lower E-staging results., Conclusions: The biomechanical E-staging in KC corneas is influenced by TCT measurements and increases within the first postoperative months after CXL. On the long term, it indicates a postoperative KC stabilization, with comparable E-values to preoperatively at 11 and 23 months after CXL., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 Asia-Pacific Academy of Ophthalmology. Published by Wolters Kluwer Health, Inc. on behalf of the Asia-Pacific Academy of Ophthalmology.)

Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht.

Purpose: To investigate the effectiveness of nonsteroidal anti-inflammatory eye drops (NSAIDs) combined with oral acetazolamide for postoperative macular edema (PME) after uncomplicated phacoemulsification (PE) and identify predictors of non-response., Methods: We analyzed data of uncomplicated PE and identified eyes with PME. First-line therapy included topical NSAIDs combined with oral acetazolamide. In the case of non-response, triamcinolone was administered subtenonally. Outcome measures included best-corrected visual acuity (BCVA) and central macular thickness (CMT)., Results: 94 eyes out of 9750 uncomplicated PE developed PME, of which 60 eyes were included. Follow-ups occurred 6.4 ± 1.8, 12.5 ± 3.7 and 18.6 ± 6.0 weeks after diagnosis. BCVA and CMT improved significantly in all follow-ups. In total, 40 eyes showed a response to first-line therapy at the first follow-up (G1). The remaining 20 eyes showed no response and required subtenon triamcinolone (G2), of which 11 eyes showed complete regression at the second follow-up and 4 eyes at third follow-up. A further 5 eyes showed no response and required intravitreal injection. Multivariate linear regression model showed that Diabetes mellitus (DM) and increased cumulative dissipated energy (CDE) are predictors of non-response., Conclusion: Topical NSAIDs with acetazolamide resulted in complete regression of PME in 67% of all cases. DM and increased CDE might be considered as predictors of non-response to this treatment.

Purpose: To evaluate the effectiveness of epithelium-off (epi-off) accelerated corneal crosslinking (A-CXL, 9 mW/cm 2 , 10 min) in adult keratoconus (KC) patients., Methods: The study included 151 KC corneas (124 patients) after A-CXL. The parameters best corrected visual acuity (BCVA) and the tomographic readings (Pentacam HR, Oculus, Germany) were analysed at 24, 12 and 6 months preoperatively, prior to surgery; and 6 weeks, 6 months, 1, 2 and >2 years postoperatively. The demarcation line was assessed by anterior segment optical coherence tomography (Tomey SS-1000, CASIA 2 (Tomey, Nagoya, Japan))., Results: Comparing pre- to postoperative findings 6 weeks after A-CXL with paired t-test, the anterior steep (46.8 ± 4.0|47.1 ± 4.1), flat (50.2 ± 4.3|50.6 ± 4.6) and maximal keratometry (57.6 ± 6.8|58.3 ± 6.8) increased (p < 0.05), while the thinnest pachymetry decreased significantly (459 ± 39|444 ± 42, p < 0.05). Lateron, however, there was a decreasing anterior flat (1, 2 and >2 years; p < 0.0001), mean (1 year; p = 0.01 and 2 years; p = 0.03) and maximal keratometry (1, 2 and >2 years; p < 0.0001). The posterior corneal keratometry readings did not change significantly until >2 years after A-CXL (MANOVA; steep, p = 0.008; flat, p = 0.027; mean, p = 0.007). The mean depth of the demarcation line was 242 ± 62 µm (53.6%). The preoperative logMAR BCVA (0.35 ± 0.02) decreased 6 weeks after A-CXL (0.39 ± 0.03) followed by a continuous improvement until the latest follow-up (0.18 ± 0.04)., Conclusion: A-CXL constitutes a successful method for KC stabilization. Signs of KC progression occur within the first 6 weeks postoperatively ("pseudoprogression"), but this is not indicative of the long-term effect.

Background: Excimer laser-assisted phototherapeutic keratectomy (PTK) has become established as the gold standard in treatment of epithelial basement membrane dystrophy (EBMD), commonly also known as map-dot-fingerprint dystrophy (MDF). At the Department of Ophthalmology, Saarland University Medical Center in Homburg/Saar, systems from Zeiss Meditec and Schwind have been used. The outcomes of both were compared in this study., Patients and Methods: The retrospective study included patients who underwent PTK with a diagnosis of MDF between 2007 and 2017. A total of 170 operations were performed using Zeiss Meditec MEL-70 (Carl Zeiss Meditec AG, Jena, Germany) and 98 using a Schwind eye-tech-solutions Amaris 750S laser (Schwind eye-tech-solutions GmbH, Kleinostheim, Germany). Preoperative and postoperative data for visual acuity, refraction and astigmatism as well as curvature data from the Pentacam and endothelial cell count were collected. The follow-up period averaged 8 months., Results: In both groups visual acuity postoperatively was significantly better (Zeiss: p < 0.001, Schwind p < 0.004). The improvement in the Schwind group was less than in the Zeiss group, which is the reason why there was a significant difference between the laser systems postoperatively (p < 0.017). There were no significant changes regarding the spherical equivalent after PTK. Regarding astigmatism, there was a significant decrease in the Zeiss group (p < 0.042), while it did not change significantly in patients treated with Schwind laser (p < 0.217). Overall, this led to a significant postoperative difference between both laser systems (p < 0.014)., Conclusion: The PTK can be recommended as an effective treatment method for patients with EBMD, regardless of the laser systems used. Patients benefit from long relief from recurrences with improved or constant visual acuity and stable refraction., (© 2022. The Author(s).)

Purpose: To analyze endothelial cell density (ECD) and central corneal thickness (CCT) following penetrating keratoplasty (PKP) in Acanthamoeba keratitis (AK) patients., Patients and Methods: In this retrospective, clinical, single-center, cross-sectional, observational study, patients were enrolled who underwent PKP at the Department of Ophthalmology of Saarland University Medical Center, Homburg/Saar, Germany between May 2008 and December 2016 with the diagnosis of AK. In all, 33 eyes of 33 patients (14 males, 42%) were enrolled; their mean age at the time of surgery was 39.5 ± 14.3 years. Postoperatively, AK patients received topical polyhexamethylene biguanide, propamidine isethionate, neomycin sulphate/gramicidin/polymixin B sulfate, and prednisolone acetate eye drops (5 ×/day each), and the topical treatment was tapered sequentially with 1 drop every 6 weeks over 6 months. CCT was recorded using Pentacam HR Scheimpflug tomography and ECD with the EM-3000 specular microscope before surgery and 3 and 6 months after surgery as well as after the first and second (complete) suture removal., Results: ECD tended to decrease significantly from the time point before surgery (2232 ± 296 cells/mm 2 ) to the time point 3 months after surgery (1914 ± 164 cells/mm 2 ; p = 0.080) and to the time point after the first suture removal (1886 ± 557 cells/mm 2 ; p = 0.066) and decrease significantly to the time point after the second suture removal (1650 ± 446 cells/mm 2 ; p = 0.028). CCT did not change significantly over the analyzed time period (p ≥ 0.475)., Conclusion: In AK, endothelial cell loss does not seem to be accelerated following PKP, despite the postoperative use of diamidine and biguanide. A subsequent prospective comparative study should confirm our retrospective longitudinal analysis., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Purpose: The purpose of this study was to assess the impact of early diagnosis using in vivo confocal microscopy and early therapeutic penetrating keratoplasty (TPK) on the outcomes of severe cases of fungal keratitis., Methods: This retrospective single-center study included 38 patients (40 eyes) with fungal keratitis who presented between December 2013 and February 2020. Preoperative, intraoperative, and postoperative parameters were recorded to assess the role of early correct diagnosis and early surgical therapy on visual acuity outcome and enucleation rate during follow-up., Results: The mean patient age was 51 years (71% females). The initial external diagnosis was correct in 20 cases (50%). The mean time from symptom onset until admission to our department was 46.8 ± 68.0 (median 28.5) days. The mean time to correct diagnosis after admission to our department was 1 day with in vivo confocal microscopy (IVCM). IVCM was performed in 38 cases, of which 36 (sensitivity: 94.7%) were positive for fungal infection. Twenty-seven out of 40 (67.5%) eyes received a TPK 4.2 ± 3.9 days after admission, with a mean graft size of 8.9 ± 1.9 mm. Three eyes (7.5%) were enucleated. The corrected distance visual acuity of the entire study population increased from 2.0 ± 1.2 LogMAR to 0.96 ± 1.17 LogMAR., Conclusion: In vivo confocal microscopy is a powerful tool for the early detection of fungal organisms in infectious keratitis. An early TPK with a large graft helps to eradicate the infection timely and results in a favorable visual acuity outcome and lower enucleation rate, especially when treating filamentous fungi., (© 2022 Sourlis et al.)

Purpose: To analyze the histological and (ultra)structural stromal tissue changes after femtosecond (Fs) laser-assisted intracorneal ring segment (ICRS) implantation and their refractive and topographic effects in patients with keratoconus., Methods: This monocentric retrospective case series included 15 consecutive patients with clinical peri-segmental lamellar channel deposits after treatment with Fs-ICRS implantation for keratoconus. The stromal changes were investigated using in vivo confocal microscopy. Two patients underwent a penetrating keratoplasty after the Fs-ICRS implantation; the explanted corneas were processed for histopathology and transmission electron microscopy (TEM). Refractive and topographic effects were investigated comparing the uncorrected (UDVA) and corrected (CDVA) distance visual acuity, spherical equivalent (SE), flat (K1), steep (K2), and steepest (Kmax) keratometry before and after detection of lamellar channel deposits., Results: In vivo confocal microscopy revealed diffuse linear and focal granular hyperreflective structures. Histologically, there was mild proliferation of fibroblasts and fibrosis. TEM demonstrated focal accumulations of degenerated keratocytes with cytoplasmic lipid inclusions. There were no significant changes for UDVA (Δ = 0.0 ± 0.2 logMAR; p = 0.67), CDVA (Δ = 0.0 ± 0.1 logMAR; p = 0.32), SE (Δ 0.1 ± 0.9 D; p = 0.22), K1 (Δ = 0.3 ± 1.0 D; p = 0.28), K2 (Δ = 0.1 ± 0.9 D; p = 0.51), and Kmax (Δ = 0.3 ± 1.5 D; p = 0.17)., Conclusions: Two types of structural stromal changes were identified: (1) diffuse peri-segmental fibrosis and (2) lamellar channel deposits. These structural changes showed no evidence of a relevant refractive or topographic effect., (© 2022. The Author(s).)

Corneal transplantation is the most commonly performed human tissue transplantation procedure worldwide. Due to the large number of grafts, corneal graft failure has become one of the most common indications for corneal transplantation for immunological and non-immunological reasons (e.g. recurrence of underlying disease, high intraocular pressure, grafted guttae, transmitted HSV or CMV infection). The relatively recently developed lamellar grafting techniques have introduced certain potential complications that may lead to graft failure and require approaches other than penetrating keratoplasty for re-grafting. On the other hand, these new lamellar techniques also offer new possibilities for salvaging failed penetrating grafts, with potential advantages over successive penetrating keratoplasties, such as lower intraoperative risks, faster visual rehabilitation and reduced risk of immune reaction. Today, the patient with good healing who is satisfied with his graft before endothelial decompensation, with low astigmatism and no stromal scars, represents the optimal condition for DMEK after PKP. This can also be combined with phacoemulsification (so-called triple DMEK). Otherwise, a penetrating re-keratoplasty with a larger graft (typically excimer laser repeat PKP 8.5/8.6 mm) is performed to treat edema, scars and irregular astigmatism simultaneously. The medical history carries weight in this decision! Re-DMEK in case of graft failure after DMEK and DSAEK does not require any modification of the standard technique and leads to good visual acuity results if performed quickly. If there is clear stromal scarring after multiple (external) DMEKs, PKP can also be considered to rectify the situation. Otherwise causeless recurrent graft failures must suggest herpetic or CMV endotheliitis and, after PCR analysis of the aqueous humour aspirate, be treated appropriately with medication., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht./The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Purpose: The aims of this meta-analysis were to evaluate the results of intracorneal ring segments (ICRSs) and MyoRing in the management of corneal ectasia and to compare the clinical outcomes and complication rates between mechanical and femtosecond (FS) laser-assisted surgery., Methods: An online electronic search was performed for pre-post studies published until April 2020. Uncorrected distance visual acuity, corrected distance visual acuity, sphere, cylinder, spherical equivalent, steep, flat, and mean keratometry values were considered as outcomes. Weighted mean difference with 95% confidence interval was used as a pooled estimation of intervention efficacy., Results: Of 1484 potentially related studies, 115 studies were finally included in the meta-analysis. Findings of this meta-analysis demonstrated considerable improvement in visual, refractive, and keratometric outcomes in all ICRS models and MyoRing. Intrastromal tunnel creation with both methods yielded similar results. Complication rates were without exception higher when mechanical dissection was used., Conclusions: ICRS and MyoRing are appropriate treatment options for patients with corneal ectasia. Both techniques for tunnel creation are efficacious in achieving good visual, keratometric, and refractive results. Mechanical intrastromal tunnel creation is associated with much higher complication rates when compared with FS laser-assisted technique., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Corneal scars can severely impair visual performance and treatment can be challenging. The study aimed to evaluate a promising minimally invasive option in the treatment of corneal scars using transepithelial topography-guided ablation., Methods: This retrospective interventional study involved four eyes of four patients who developed corneal scarring and irregular surfaces due to trauma and were treated with topography-guided photorefractive keratectomy (TG-PRK) between 2017 and 2020. The ablation profile was calculated in all four cases using CRS-Master (Zeiss, Jena, Germany). The main outcome measures were uncorrected and best-corrected distance visual acuity, manifest refraction and corneal regularity by topographic images. The mean age was 34.75 ± 15.39 years and the follow-up time was 6 months for all patients., Results: In three cases full subjective refraction was corrected in one session and one patient had a refractive error of +0.5 D. Only corneal surface smoothing without additional refractive correction was performed in this case. All four patients showed improvement in uncorrected (2-3 Snellen lines) and corrected (3 Snellen lines) distance visual acuity. No complications occurred during or after the treatment and there was no reduction of visual acuity in any case., Conclusion: The use of TG-PRK in patients with corneal scarring improves visual acuity in selected cases. In myopic patients most of the refractive error can also be corrected in a single session., (© 2021. Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Background: This study assesses the reliability of successive corneal biomechanical response measurements by the Corneal Visualization Scheimpflug Technology (CST, Corvis ST ® , Oculus Optikgeräte, Wetzlar, Germany) in different keratoconus (KC) stages., Methods: A total of 173 eyes (15 controls: 15 eyes, and 112 KC patients: stages 1|1-2|2|2-3|3|3-4|4, n = 26|16|36|18|31|26|5 according to Topographical KC Classification, TKC) were repeatedly examined five times with the CST, each after repositioning the patient's head and re-adjusting the device. Tomographical analysis (Pentacam HR ® ; Oculus, Wetzlar, Germany) was performed once before and once after CST measurements. Outcome measures included (1) A1 velocity, (2) deformation amplitude (DA) ratio 2 mm, (3) integrated radius, (4) stiffness parameter A1 and (5) Ambrósio relational thickness to the horizontal profile (ARTh). The Corvis Biomechanical Index (CBI) is reported to be extracted out of these parameters. Mean values of the five measurements and Cronbach's α were calculated as a measure for reliability., Results: Ambrósio relational thickness to the horizontal profile and SPA1 were significantly higher in controls (534|123) compared to TKC1 (384|88), TKC2 (232|66), TKC3 (152|55) and TKC4 (71|27; p < 0.0001). The other parameters were similar in controls and TKC1 (A1 velocity: 0.148|0.151 m/s; integrated radius: 8.2|8.6 mm -1 ), but significantly higher in TKC stages 2 to 4 (DA ratio 2 mm: 5.5|6.3|8.0; A1 velocity: 0.173|0.174|0.186 m/second; integrated radius: 10.9|12.8|19.0 mm -1 ; p < 0.0001). All parameters proved to be highly reliable (Cronbach's α ≥ 0.834) and the corneal tomography remained unaffected., Conclusions: The individual parameters included in the CBI (consisting of ARTh, SPA1, DA ratio 2 mm, A1 velocity and integrated radius) are highly reliable but differ KC stage-dependently., (© 2021 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

Background: We present the results of penetrating keratoplasty (PKP) after previous treatment with a total conjunctival flap in two patients., Case Reports: Patient 1, a 66-year-old with a history of bilateral cement chemical burn in 1986 and external right-sided limbokeratoplasty in 2008 was treated externally with a total conjunctival flap in the right eye in 2014 due to a persistent corneal ulcer with imminent perforation. Best-corrected visual acuity (BCVA) in the right eye was light sensation, intraocular pressure on palpation was within normal range. Clinically, total conjunctival flap was present. Patient 2 was treated externally in May 2015 due to acanthamoeba keratitis in the left eye with a deep anterior lamellar keratoplasty (DALK). A re-DALK was also performed externally in the same month. A third DALK was performed externally in August 2015 due to a persistent corneal ulcer, followed by a total conjunctival flap 2 weeks later. BCVA of the left eye was light sensation and intraocular pressure on palpation was within the normal range., Results: Patient 1 was treated with removal of the conjunctival flap in the right eye and penetrating central re-keratoplasty (hand-held Barron trephine; graft diameter 8.5/8.75 mm). Simultaneously, lens extraction and intraocular lens implantation were performed (as a triple procedure). Additionally, amniotic membrane transplantation (AMT) as patch and a temporal lateral tarsorrhaphy were performed. BCVA 6 months postoperatively was 0.1. The graft was clear, without any signs of rejection. Patient 2 was treated on the left eye with removal of the conjunctival flap and a penetrating central keratoplasty (hand-held Barron trephine; graft diameter 7.0/7.5 mm). An AMT as patch and a temporal lateral tarsorrhaphy were simultaneously performed. Cataract surgery was performed 3 months postoperatively and BCVA of the right eye was 0.1 thereafter. The graft was clear, without any signs of rejection., Conclusion: The conjunctival flap is a treatment of last resort of the (almost) penetrated corneal ulcer, which is to be used only when a keratoplasty is technically impossible. Provided the eye structure and retinal function are preserved, partial visual rehabilitation can possibly be achieved through a PKP after excision of the conjunctival flap, even years after corneal blindness., (© 2021. Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Background: With the increasing demand for corneas, eye banks must optimize the tissue donation, collection, and selection process. This retrospective monocentric study analyzed the approval rates for corneal donation and the origin of and reasons for discarding donor corneas from 2010 to 2019., Methods: Data included the number of deceased, approval or rejection by the family for corneal donation and contraindications. Corneal grafts were included from all deceased persons who were full-body and multi-organ donors at the Saarland University Medical Center (UKS) and from external institutions. Additional analyzed parameters included endothelial cell count (ECC), blood sample serology for infections, and conjunctival swab testing ., Results: A total of 1748 corneoscleral buttons were harvested from 10,265 deceased persons (17% with no contraindication) at the UKS between 2010 and 2019, with a consent rate of 23.3%. The number of keratoplasties increased from 136 in 2010 (15% of the deceased, total = 925) to 251 in 2019 (21%, total = 1214). Both the general and department-specific data showed similar percentages for corneal donation over the years, with intensive care and palliative units recently providing the most corneas. The increase in the number of corneas processed by the cornea bank over the years (368 in 2010 compared with 857 in 2019) was linked both to a better internal supply in 2010 (262, 71.2% of the total) compared with 2019 (519, 60.6%) and to an external supply by reinforcement of cooperation with external hospitals, including Luxembourg in 2010 (106, 28.8% of the total) compared with 2019 (338, 39.4%). A total of 195 of 377 corneas (52%) were discarded in 2009 compared with 260 out of 715 (36%) in 2019. The main reasons for discarding were low ECC (36% of discarded corneas in 2009; 11% in 2019), positive conjunctival swab (11% in 2009; 13% in 2019), and blood sample serology (6% in 2009 and in 2019)., Conclusion: Despite an increasing number of donors, the demand for corneas is still rising. Improved cooperation with internal departments and with external clinics has led to an increasing number of explanted corneas. The main reason for discarding corneas was low ECC, followed by a positive conjunctival swab for fungal or bacterial contamination and serology. Increased donation rates and continued improvements in collection and selection processes are necessary to cover the high demand for corneas., (© 2022. The Author(s).)

Fusarium spp. are moulds ubiquitously distributed in nature and only occasionally pathogenic for humans. Species of the Fusarium solani complex are the predominant keratitis-inducing pathogens, because they are endowed with proper virulence factors. These fungi can adhere to the cornea creating a biofilm and, with the help of enzymes and cytotoxins, penetrate the cornea. Whereas an intact cornea is hardly able to be invaded by Fusarium spp. in spite of appropriate virulence factors, these opportunistic fungi may profit from predisposing conditions, for example mechanical injuries. This can lead to a progressive course of corneal infection and may finally affect the whole eye up to the need for enucleation. Here, we present and discuss the clinical, microbiological and histopathological aspects of a particular case due to Fusarium tonkinense of the Fusarium solani complex with severe consequences in a patient without any obvious predisposing factors. A broad portfolio of antifungal agents was applied, both topically and systemically as well as two penetrating keratoplasties were performed. The exact determination of the etiologic agent of the fungal infection proved likewise to be very challenging.

Background and Objectives: The Homburg cross-stitch marker, according to Suffo, was developed in 2017 in the Department of Ophthalmology at Saarland University Medical Center. With this instrument, a surgeon can precisely define and mark the points of the first and second continuous cross-stitch sutures, according to Hoffmann. The aim of this retrospective study was to compare the functional outcomes of Hoffmann's double continuous cross-stitch suture in penetrating keratoplasty (PKP) with vs without the Homburg cross-stitch marker in inexperienced surgeons., Methods: A total of 130 eyes from 130 patients with central corneal scars, corneal dystrophies and advanced keratoconus were included. All eyes underwent elective excimer laser-assisted penetrating keratoplasty (excimer laser PKP) with a diameter of 8.0/8.1mm. In 65 eyes each, surgery was performed without (group 1) or with (group 2) the Homburg cross-stitch marker. Corrected distance visual acuity, topographic astigmatism, and refractive cylinder were obtained 6 weeks, 10 months post-PKP as well as 6 weeks after the first and after the second suture removal, respectively. The rate of early postoperative single interrupted suture addition was compared between the two groups., Results: Visual acuity, astigmatism and refractive cylinder values were significantly more favorable in group 2 (with device) compared to group 1 (without device) before and after suture removal. Postoperative single interrupted suture addition was performed in 34.4% of patients in group 1 compared to 10.6% in group 2 ( P = 0.001, Fisher's Exact Test)., Conclusion: The use of the Homburg cross-stitch marker for excimer laser PKP in young cornea specialists results in significantly better visual acuity before and after suture removal, significantly lower astigmatism and cylinder value before suture removal, as well as a reduced necessity of early postoperative single interrupted suture addition., Competing Interests: The authors declare no conflicts of interest., (© 2021 Suffo et al.)

Indications: The aim of excimer laser-assisted deep anterior lamellar keratoplasty (excimer-DALK) is, as in mechanical DALK, the treatment of keratectasia (keratoconus and pellucid marginal degeneration), stromal scars or stromal corneal dystrophy. A prerequisite for surgery is the absence of (pre‑) Descemet's scars and an intact endothelium., Surgical Technique: After excimer laser-assisted trephination to 80% of the corneal thickness at the trephination site, intrastromal air injection (so-called big bubble) and lamellar corneal preparation, a lamellar anterior transplantation of the endothelium-free donor tissue is performed. The technique combines the advantages of DALK and excimer laser trephination. We describe the steps of an excimer-DALK from the Homburg Keratoconus Center (HKC)., Conclusion: Excimer-DALK is a viable treatment option for patients with intact endothelium. In cases of intraoperative perforation, conversion to excimer-perforating keratoplasty (PKP) with all the advantages of excimer laser trephination remains feasible., (© 2021. The Author(s).)

Purpose: This study assesses the reliability of successive measurements of tomographic parameters in different keratoconus (KC) stages with 2 different devices., Methods: A total of 125 eyes (13 controls: 24 eyes, and 73 patients with KC: stages 1|2|3|4, n = 24|24|26|27 according to Topographical KC Classification) were repeatedly examined 5 times with the rotating Scheimpflug tomograph (Pentacam HR, Oculus, Wetzlar, Germany) and an anterior segment optical coherence tomograph (Casia 2, Tomey, Nagoya, Japan). Outcome measures included 1) mean anterior (KA) and 2) mean posterior powers (KP), 3) mean anterior (AC) and 4) posterior cylinders (PC), 5) maximal anterior power (Kmax), and 6) thinnest corneal thickness (TCT). The results were compared using the Wilcoxon matched pairs test considering P values <0.05 as statistically significant. Standard deviations (SDs) of repeated measurements with both devices were compared between and within the KC stages., Results: The Pentacam values for PC, Kmax, and TCT were significantly elevated compared with those of the anterior segment optical coherence tomograph (P < 0.0001). The SDs of successive measurements of KA and KP, AC and posterior cylinders, Kmax, and TCT increased from (Casia 2|Pentacam) 0.10|0.09 diopter (D), 0.01|0.02 D, 0.15|0.08 D, 0.02|0.05 D, 0.17|0.18 D, and 0.92|5.25 μm in controls to 0.47|0.66 D, 0.1|0.2 D, 0.86|0.9 D, 0.17|0.3 D, 0.89|1.65 D, and 7.68|15 μm in TKC4. Significant differences occurred between the 2 devices for eyes within the same KC stage., Conclusions: The reproducibility of measurements decreases with increasing KC severity in both devices. Although both devices seem reliable, the interdevice differences regarding measured tomographic parameters lead to the conclusion that Pentacam HR and Casia 2 measurements are not interchangeable in neither healthy nor KC corneas., Competing Interests: E. Flockerzi has received a travel grant to the Second and Third Ophthalmology Cystinosis Forum (Orphan Europe, Ulm, Germany) and an invitation to a seminar on presentation training organized by the Santen GmbH (Munich, Germany). T. Eppig was a member of the Institute of Experimental Ophthalmology, Saarland University Medical Center (Homburg, Germany), at the time of data collection and is now an employee of the Amiplant GmbH (Schnaittach, Germany). The remaining authors have no conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: Fungal keratitis (FK) is a serious ophthalmic disease with a potentially devastating outcome that seems to be increasing in recent years. The use of contact lenses (CLs) was evaluated as a risk factor for FK to determine possible differences in course and outcome., Methods: Data from 173 cases reported in the German FK registry until August 2019 were evaluated regarding CL behavior, other ophthalmological and general risk factors, age, sex, identified pathogens, conservative and surgical therapy, visual acuity, and findings at admission and follow-up., Results: One hundred seventy-four eyes from 173 patients between 2000 and 2019 were included [64.4% women, median age 54 (39; 72) years]; 49.7% wore CL, of which 81.3% were soft CL, and 50.3% had no history of contact lens use (NCL). CL users were significantly more often women and otherwise healthy (CL: 80.2% vs. NCL: 48.9%; P < 0.0001). The spectrum of pathogens among CL users showed a significantly higher proportion of infections with filamentous pathogens, in particular Fusarium sp. (total filament: CL 69.8% vs. NCL 27.3%; P = 0.0001; Fusarium sp.: CL 50.0% vs. NCL 14.8%; P < 0.0001). Overall, 54.6% required keratoplasty and 8.6% enucleation., Conclusions: CLS are the most important risk factor for FK in Germany. With CLs, typically, the infection is caused by molds, and patients are comparably younger and otherwise healthy. Often, extensive surgery is needed. To evaluate changes in the pathogen and resistance spectrum and to further monitor possible CL-related risk factors, a consistent collection of data remains paramount., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To evaluate the results and complications of Descemet membrane endothelial keratoplasty (DMEK) in previously vitrectomized eyes., Design: Retrospective study of 35 eyes that had undergone DMEK, due to Fuchs endothelial corneal dystrophy (FECD), at our department with a follow-up after 6 months postoperatively. We compared the intraoperative procedure, complications, and results of DMEK between 14 previously vitrectomized pseudophakic eyes (group 1) and a control group of 21 pseudophakic non-vitrectomized eyes (group 2)., Results: The unfolding time (in minutes) was significantly longer in group 1 than in group 2 (10.5 ± 6.4 vs. 3.2 ± 1.5, p < 0.01). A single re-bubbling was needed in 8 patients in group 1 (57.1%) and in 3 patients in group 2 (14.2%) (p < 0.01). Repeated re-bubbling (≥ 1 time) was performed in only 5 patients of group 1 (35.7%). There was significant postoperative improvement in best-corrected visual acuity (BCVA, in LogMAR) in both groups (p = 0.04 in group 1 and p < 0.01 in group 2). The central corneal thickness (CCT, in µm) did not differ significantly between the two groups preoperatively (p = 0.4) or postoperatively (p = 0.1). However, the CCT decreased significantly postoperatively in both groups (p < 0.01 in both groups). The postoperative endothelial cell density (ECD in cell/mm²) was significantly lower in group 1 than in group 2 (p = 0.03)., Conclusion: DMEK in previously vitrectomized eyes presents a surgical challenge, which requires special, and sometimes unpredictable, intraoperative maneuvers, but good functional and morphological results can be achieved. The use of the endothelial Descemet membrane lamellae (EDML) of older donors might be recommended to facilitate the intraoperative unfolding process., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Keratoconus (KC) is a progressive cone-shaped corneal protrusion that causes paracentral thinning at the apex of the cone and typically occurs asymmetrically on both sides. After a careful anamnesis and classification of the degree of severity a targeted treatment appropriate to the stage of the disease is available. If the visual acuity is no longer sufficient, rigid gas-permeable contact lenses (CL) are fitted by a specialist. Riboflavin UVA cross-linking (CXL) is recommended in cases of progression and visual acuity that is still useful for the patient. Intracorneal ring segments (ICRS) are indicated for CL intolerance in cases of reduced visual acuity and a clear central cornea. If the stage is more advanced, deep anterior lamellar keratoplasty (DALK) or penetrating keratoplasty (PKP) is recommended. A PKP is contraindicated in acute KC but deep stromal sutures for readaptation of the Descemet tear with gas filling of the anterior chamber can considerably shorten the course. Almost no other eye disease is nowadays as easily accessible for an early instrument-based diagnosis and stage-appropriate treatment as KC., (© 2021. The Author(s).)

Contact lens-associated keratitis is becoming increasingly more frequent. Fungal keratitis is a relatively rare clinical picture but must be taken very seriously. Especially in the early stages of the disease, it may be clinically misdiagnosed and adequate treatment is therefore delayed. In treatment-resistant contact lens-associated fungal keratitis, coinfections or superinfections can occur. We present two patients with an initially unclear keratitis, in whom a fungal keratitis with coinfection of Pseudomonas aeruginosa and Acanthamoeba, respectively, could be confirmed. In both cases an urgent excimer laser penetrating keratoplasty with interrupted sutures and adequate local topical treatment for 8 weeks was successful., (© 2020. The Author(s).)

Introduction: Until now, the double-running cross-stitch according to Hoffmann used in penetrating keratoplasty (PKP) has been routinely carried out by simply using a sense of proportion. As a result, the estimation of the precisely defined entry and exit points of the sutures and, by extension, the success of the running cross-stitch suture was completely dependent on the practical experience of the surgeon. Therefore, we introduced the cross-stitch marker as a supporting instrument for PKP surgery., Methods: Description of the Homburg cross-stitch marker with an exact step-by-step guide on how the instrument is implemented while performing a PKP to mark entry and exit points for sutures including a video to demonstrate the use of this instrument., Results: The new Homburg cross-stitch marker ensures the precise localisation of the entry and exit points of the suture. This new instrument allows inexperienced surgeons in particular to feel very confident when performing the running sutures., Conclusion: Surgeons with little experience can completely avoid using their still imprecise sense of proportion and significantly shorten the learning curve for this procedure., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

We report a Patient with Fuchs dystrophy who underwent three Descemet Membrane Endothelial Keratoplasties (DMEK) caused by recurrent graft failure with raise in intraocular pressure and cystoid macular edema. At the third DMEK, herpes was detected in the anterior chamber tap and an adequate therapy was initiated. At the 6 months follow-up the cornea remained clear, visual acuity was 0.8, intraocular pressure was within normal range and macular edema regressed completely. Either a latent Herpes simplex Virus (HSV) infection of the patient was reactivated or an infected donor lamella was transplanted with donor-to-host-to-donor ping-pong transmission.

Background: Cornea guttata may not be recognized in the eye bank and recent studies have displayed that guttae are transplanted in about 15% of cases in varying severities. The purpose of this study was to establish semiquantitative criteria for the detection of cornea guttata in donor corneas in the eye bank., Methods: In this retrospective cohort study, preoperative endothelial pictures of donor corneas were collected and classified according to the post-penetrating keratoplasty cornea guttata grade into three distinct groups: group 1 consists of healthy corneas with no guttae (guttata grade 0); group 2 constitutes corneas with mild asymptomatic cornea guttata (guttata grade +); and group 3 comprises corneas with advanced widespread cornea guttata (guttata grade ++/+++/++++). The preoperative pictures of each group were then individually analyzed using the following five semiquantitative criteria: The number and the area of the cell-depleted surfaces, the presence of less than 50% of the cells having a hexagonal or a circular shape, the presence of cell membrane defects and interruptions, the presence of blebs in the cell membrane, and the presence of groups of cells with a distinct whitish color., Results: In total, 262 patients were included in this study, with a total number of 1582 preoperative donor corneal endothelial pictures. Out of those pictures, groups 1, 2, and 3 encompassed 995 (62.9%), 411 (26.0%), and 176 (11.1%) pictures, respectively. Three out of the five eye bank criteria were found to correlate with postoperative cornea guttata with a highly significant p value of < 0.001. These three criteria are the presence of less than 50% of the cells having a hexagonal or a circular shape, the presence of cell membrane defects and interruptions and, the presence of blebs. The presence of groups of cells with a distinct whitish color was only a weak predictive factor for cornea guttata (p = 0.069). There was no statistically significant correlation between the number and the area of cell-depleted surfaces and postoperative cornea guttata with a p = 0.181., Conclusion: Three semiquantitative criteria that can be detected in the eye bank using inverted light microscopy seem to correlate with postoperative cornea guttata: The presence of blebs, the presence of cell membrane defects and interruptions, as well as endothelial pictures with less than 50% of the cells having a hexagonal of circular shape. The presence of groups of cells with a distinct whitish color appears to be a weak predictor of cornea guttata., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Purpose: To determine the changes of corneal thickness and curvature of human corneal grafts in organ culture medium II, containing dextran T500 6%, before keratoplasty., Methods: We examined the tomography of 24 corneas from our eye bank transferred from medium I into medium II. Images were repeated hourly during 24 hours using an anterior segment optical coherence tomography. The central corneal thickness (CCT) was measured with the manual measurement tool of the anterior segment optical coherence tomography. The radii of curvature (anterior flat and steep and posterior flat and steep) were measured with a MATLAB self-programmed software for "sterile donor tomography.", Results: The mean CCT (±SD) at baseline (T0) was 727 ± 156 μm. It reached 581 ± 103, 506 ± 84, 472 ± 79, and 456±7 μm after 6, 12, 18, and 24 hours, respectively. After 12 hours, 83% of the final deswelling was achieved. The radii of curvature (±SD) at baseline (T0) were (posterior flat, posterior steep, anterior flat, and anterior steep) 6.6 ± 0.5, 6.2 ± 0.5, 7.7 ± 0.4, and 7.4 ± 0.4 mm, respectively. After 24 hours, the radii of curvature reached 6.8 ± 0.1, 6.6 ± 0.3, 7.6 ± 0.1, and 7.4 ± 0.2 mm, respectively., Conclusions: The kinetics of the deswelling process in medium II follow a hyperbolic curve. Considering a CCT of 506 μm at T12, we assume that a time interval of 12 hours in medium II might be enough for clinical purposes. This result might help to keep storage in medium II as short as possible to escape potential toxic effects of dextran in medium II. The radius of curvature does not seem to change within 24 hours for all measured surfaces., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To evaluate the efficacy, safety, and predictability of transepithelial photorefractive keratectomy (TransPRK) for correcting myopia, astigmatism, and hyperopia., Setting: Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar, Germany., Design: Meta-analysis of retrospective or prospective studies., Methods: Relevant studies were collected from Medline and included when meeting the following predefined criteria: randomized controlled trials, at least 1 of the main outcome measures as efficacy, safety, or predictability, and 1 common TransPRK laser (Schwind Amaris). The parameters estimates and 95% CI were derived from random-effects meta-analysis to account for possible heterogeneity., Results: Because hyperopia studies did not meet the inclusion criteria, the results are centered on myopia and astigmatism. Sixteen studies with a total of 1924 treated eyes were included in the meta-analysis. The mean efficacy, safety, and predictability had a probability of 94% (CI, 0.86-0.97), 0% (CI, 0.00-0.03), and 89% (CI, 0.82-0.93), respectively. The mean correction index, difference vector, and index of success had a value of 1.01 (CI, 1.01-1.02), 0.20 (CI, 0.06-0.34), and 0.12 (CI, 0.07-0.18), respectively., Conclusions: This summary estimate showed that TransPRK was highly effective, safe, and predictable in correcting myopia and/or astigmatism., (Copyright © 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Purpose: To point out the biomechanical changes of the topographically and tomographically normal partner eye (NPE) in patients with very asymmetrical corneal ectasia., Setting: Department of Ophthalmology, Saarland University Medical Center in Homburg/Saar, Germany., Design: Retrospective study., Methods: The topographical and tomographical results of the NPE were assessed using the Pentacam HR and the biomechanical corneal properties using the Ocular Response Analyzer (keratoconus match index [KMI], corneal hysteresis [CH], and corneal resistance factor [CRF]) and the Corvis ST (topographic biomechanical index [TBI] and Corvis biomechanical index) and compared those results with a normal control group (CG)., Results: The clinical records of 26 patients recruited from the Homburg Keratoconus Center diagnosed with a very asymmetrical corneal ectasia were reviewed. The NPE (8.5 ± 1.5 mm Hg) showed a significantly more pathological CH (P < .001) compared with the CG. The CRF was also significantly more pathological (P = .04) for the NPE (8.3 ± 1.5 mm Hg) compared with the CG. The NPE (0.62 ± 0.32) showed a nonsignificant (P = .08) more pathological KMI compared with the CG. Nineteen (73.1%) of 26 NPE had a KMI less than 0.72 and were considered pathological. Compared with the CG, the TBI of the NPE (0.19 ± 0.25) did not differ significantly overall (P = .57). However, 5 (19.2%) of 26 eyes had a TBI more than 0.29 and were considered pathological., Conclusions: Topographically and tomographically NPEs in very asymmetrical corneal ectasia frequently showed biomechanical changes. This should be considered before planning any type of refractive corneal surgery in such patients., (Copyright © 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)