Fuchs Endothelial Dystrophy Research Articles

Ten-Year Follow-Up After Descemet Membrane Endothelial Keratoplasty.

To examine clinical results up to 10 years after Descemet Membrane Endothelial Keratoplasty (DMEK) and Triple-DMEK. Prospective study including 201 eyes, of which 54 eyes [38 DMEKs and 16 Triple-DMEKs; Fuchs endothelial dystrophy (n = 45), pseudophakic bullous keratopathy (n = 9)] reached the minimum follow-up of 5 years and were followed up for up to 10 years. We evaluated best-corrected visual acuity (BCVA, logarithm of the minimum angle of resolution [logMAR]), endothelial cell density (ECD, cells/mm2), minimal central corneal thickness (CCT, μm), central retinal thickness (μm), rebubbling, graft survival and re-DMEK rate, chamber angle alterations, and incidence of glaucoma. Fifty-four eyes had a 5-year and 37 eyes an 8- to 10-year follow-up. Mean follow-up was 94.4 ± 12.1 months. Best-corrected visual acuity increased from 0.6 ± 0.3 logMAR to 0.1 ± 0.2 logMAR at 6 months (P ≤ 0.001) and was 539 ± 54 μm at long term. Endothelial cell density decreased from 2488 ± 320.9 (donor) to 980.1 ± 437 cells/mm2 with an average ECD loss/year of 4% and did not correlate with BCVA. Central corneal thickness decreased from 596.9 ± 82.2 μm to 498.6 ± 24.3 μm at 12 months (P ≤ 0.001) and remained stable (P = 1.000). Mean rebubbling rate was 0.3 ± 0.5/eye and did not correlate with BCVA. Eight eyes (14.8%) received at least 1 rebubbling. Primary graft failure/rejection rate was 1.5%/0% within the first postoperative year, and secondary graft failure rate was 12.4% at 7 years. Eight eyes (preoperative n = 3, de novo n = 5) had open-angle glaucoma without chamber angle changes (14.8%, P ≤ 0.001). Although ECD decreases continuously in the long-term follow-up, excellent visual acuity can be preserved 10 years after DMEK and Triple-DMEK. The final outcome can be estimated 6 months after surgery.

Filling the refractive gap: The piggyback way

Corneal surface irregularities can severely affect preoperative biometry and IOL power calculation, especially in cases where combined keratoplasty and IOL implantation are planned. We report a patient with stage 3 Fuchs endothelial dystrophy who underwent a successful Descemet’s stripping endothelial keratoplasty (DSEK) triple procedure but suffered a hyperopic refractive surprise due to erroneous preoperative biometry and IOL power calculation. Six months later, we corrected the residual refractive error with a secondary piggyback IOL, a Rayner Sulcoflex aspheric IOL. Uncorrected vision improved from 5/60 to 6/9 and vision was maintained with a clear DSEK graft at 5 years follow-up. Preoperative biometric difficulties can be an important cause of postoperative refractive surprise in patients undergoing endothelial keratoplasty-triple procedures. Customized sulcus fixated IOL can be a safe and predictable option for treating such surprises. To our knowledge, ours is the first report of implantation of a piggyback IOL in an eye following DSEK.

Changing indications for keratoplasty: monocentric analysis of the past two decades

Abstract Purpose Over the past two decades, lamellar keratoplasty procedures, such as Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK) and Descemet's Membrane Endothelial Keratoplasty (DMEK) as well as Deep Anterior Lamellar Keratoplasty (DALK), have become an integral part of clinical practice. With advances in contact lens fitting for keratoconus management and the implementation of UVA-Riboflavin Crosslinking (CXL), the landscape of keratoplasty indications is undergoing changes. Procedures and indications in a single tertiary care center over the past two decades are reviewed in this retrospective analysis. Methods: Retrospective analysis utilized anonymized electronic data from the LIONS cornea bank Baden-Württemberg, Eye Center Freiburg, spanning from beginning of 2004 to end of 2023. The primary focus was on surgical procedures and indications for keratoplasty. Results The study encompassed a comprehensive analysis of 7130 corneal transplants. Penetrating keratoplasty (PK) exhibited a significant decline from 95% (n = 206, 2004) to 11% (n = 46, 2023), while DMEK increased from 48% (n = 157, 2012) to 82% (n = 347, 2023). Fuchs endothelial dystrophy (FED) emerged as the dominant indication, witnessing a significant increase from 24% (2004, n = 39) to 72% (2023, n = 288). Conversely, keratoconus (KC) showed a reciprocal change from 25% (2004, n = 40) to 4% (2023, n = 17). PK demonstrated a noteworthy indication shift in descending order from Bullous Keratopathy (BK), FED, and KC in 2004 to KC, graft failure, corneal scars, and ulcers in 2023. Repeat keratoplasty following DMEK remained rare, but a discernible upward trend was observed for PK. Conclusion This retrospective analysis highlights significant changes in both keratoplasty indications and techniques over the past two decades. DMEK has emerged as a successful intervention for treating endothelial diseases, while PK retains its qualitative indispensability for a wide range of indications. Modern corneal banks are urged to maintain a robust supply of grafts for all surgical techniques in anticipation of potential increased demand in the future, particularly for repeat keratoplasties. Key messages What is known • Over the past two decades, lamellar keratoplasty procedures such as DSAEK and DMEK have increasingly replaced penetrating keratoplasty (PK) in clinical practice due to their improved outcomes and reduced complications for certain indications. New Findings • Our study reveals a significant shift in keratoplasty indications, with Fuchs endothelial dystrophy (FED) emerging as the predominant indication, increasing from 24% in 2004 to 72% in 2023, while keratoconus (KC) declined from 25 to 4% during the same period. • Penetrating keratoplasty (PK) has shown a marked decline in use, dropping from 95% of keratoplasties in 2004 to 11% in 2023, whereas DMEK has grown to represent 82% of procedures in 2023. • Despite the rise of DMEK, PK remains vital for a broad spectrum of indications, highlighting the necessity for corneal banks to maintain a versatile supply of grafts to meet diverse clinical needs, particularly in cases of repeat keratoplasties.

Pseudo Corneal Ectasia Due to Corneal Endothelial Disease

Purpose To describe two patients referred for presumed ectasia after laser in situ keratomileusis (LASIK) based on increasing myopia and corneal steepening years after LASIK. In both patients, further testing confirmed endothelial disease with central corneal edema as the cause of topographic changes. Methods Two patients showing symptoms similar to post-LASIK ectasia were assessed with Scheimpflug imaging (Pentacam; Oculus Optikgeräte GmbH) and subsequently treated with endothelial keratoplasty. Results Case 1 was a 66-year-old woman with increasing myopia after LASIK that was initially diagnosed as post-LASIK ectasia. Pentacam imaging revealed central corneal steep-ening with central corneal edema, and the clinical presence of guttata was consistent with Fuch's endothelial dystrophy. Case 2 was a 49-year-old man who also had increasing myopia and corneal steepening after LASIK, but no guttata. Pentacam imaging showed a similar pattern of central corneal swelling. Both patients underwent endothelial keratoplasty with reversal of corneal steepening. Conclusions Several conditions can mimic corneal ectasia, necessitating thorough clinical examination and tomography. This report describes two cases of central corneal edema resulting in myopia and corneal steepening that mimicked corneal ectasia. [ Journal of Refractive Surgery Case Reports. 2024;4(3):e24–e29.]

Hepatocyte Growth Factor Modulates Corneal Endothelial Wound Healing In Vitro.

In this study, we assessed the impact of hepatocyte growth factor (HGF) on corneal endothelial cells (CECs), finding that HGF concentrations of 100-250 ng/mL significantly increased CEC proliferation by 30%, migration by 32% and improved survival under oxidative stress by 28% compared to untreated controls (p < 0.05). The primary objective was to identify non-fibrotic pharmacological strategies to enhance corneal endothelial regeneration, addressing a critical need in conditions like Fuchs' endothelial dystrophy (FED), where donor tissue is scarce. To confirm the endothelial nature of the cultured CECs, Na+/K+-ATPase immunohistochemistry was performed. Proliferation rates were determined through BrdU incorporation assays, while cell migration was assessed via scratch assays. Cell viability was evaluated under normal and oxidative stress conditions using WST-1 assays. To ensure that HGF treatment did not trigger epithelial-mesenchymal transition, which could lead to undesirable fibrotic changes, α-SMA staining was conducted. These comprehensive methodologies provided robust data on the effects of HGF, confirming its potential as a therapeutic agent for corneal endothelial repair without inducing harmful EMT, as indicated by the absence of α-SMA expression. These findings suggest that HGF holds therapeutic promise for enhancing corneal endothelial repair, warranting further investigation in in vivo models to confirm its clinical applicability.

Corneal High-Order Aberrations in Fuchs Endothelial Corneal Dystrophy and Subclinical Corneal Edema.

High-order aberrations (HOAs) are known to be increased in corneas with Fuchs endothelial dystrophy (FECD) and are associated with visual impairment. This case series aimed to analyze whether tomographic changes in FECD affect the HOA in the early period of the disease. In this retrospective single-center case series, 144 eyes of 85 patients were included, of which 78 eyes of 47 patients with FECD with slit-lamp biomicroscopically visible guttae but no visible corneal edema served as the study-cohort. According to Sun et al, included eyes were divided into 2 groups: group 0 (n = 28; no subclinical corneal edema) and group 1 (n = 50; subclinical corneal edema). A total of 66 healthy eyes of 38 patients served as control group. Mean values and standard deviations were calculated for the root mean square (RMS), coma, trefoil and spherical aberrations (SA) of the cornea (C), the anterior surface (CF), and the posterior surface (CB). Statistically significant differences (P < 0.001) in the RMS HOA (group 0: 0.209 ± 0.044 μm, group 1: 0.372 ± 0.122 μm) and in coma (group 0: 0.082 ± 0.054 μm, group 1: 0.214 ± 0.101 μm) and SA (group 0: -0.130 ± 0.038 μm, group 1: -0.176 ± 0.074 μm) of the CB were found in eyes in group 1 versus those in group 0. There were no statistically significant differences in HOA between the control group and eyes in group 0. FECD eyes with subclinical corneal edema demonstrated significant increase in RMS, coma, and SA of the CB. Tomographic analysis, therefore, helps in visual impairment assessment, disease progression, and decision-making for early endothelial keratoplasty in patients with FECD.

Outcomes of Descemet Stripping Only Without Postoperative Use of Topical Rho-associated Protein Kinase Inhibitors.

Descemet Stripping Only (DSO) is a promising surgical option for select patients with Fuchs endothelial dystrophy (FED). There is growing support for the use of topical Rho-associated protein kinase inhibitors (ROCKi) to optimize DSO outcomes. However, in many settings, ROCKi are either unavailable or not approved to treat corneal diseases. This study sought to characterize patient outcomes after DSO in the absence of ROCKi and potentially broaden the settings where DSO can be offered to patients. Single-center retrospective case series of 15 eyes/11 patients (66 years; 52-74) that underwent DSO, alone or combined with cataract surgery, by one surgeon between August 2020 and January 2023. Patients included in analyses had FED with central guttae, no clinical evidence of corneal edema, and a clinically healthy peripheral corneal endothelium. Mean follow-up time was 14 months (2-34). Fourteen of 15 eyes achieved corneal clearance (93.3%). Mean time to clearance was 8.5 weeks (3-23). Eleven eyes (73%) achieved corrected distance visual acuity of ≤0.2 with a significant postoperative improvement at 4 to 8 months (P < 0.05) and sustained improvements at >12 months. No significant astigmatism was introduced by the procedure. Two eyes developed cystoid macular edema postoperatively. A trend toward earlier clearance was observed in the <65 years old group. Despite a longer time to corneal clearance in this cohort compared with the few studies using ROCKi, the overall success rate and visual outcomes for the patients in our cohort supports the use of DSO in settings where ROCKi are not readily available.

Ophthalmology Residents' Experience in Cataract Surgery: Preoperative Risk Factors, Intraoperative Complications, and Surgical Outcomes.

This retrospective study explores the connection between preoperative patient risk factors, the experience of ophthalmology residents, and the outcomes of cataract surgeries performed at Hadassah Medical Center. It is hypothesized that with increased experience, residents may demonstrate greater proficiency in handling surgeries on higher-risk patients, potentially leading to improved surgical outcomes overall. Data were examined from 691 consecutive cataract surgeries in 590 patients, conducted by ophthalmology residents at Hadassah Medical Center (January 2018 to February 2022). Demographics, surgeon experience, preoperative cataract risk assessment score, and pre- and postoperative corrected distance visual acuity (CDVA) were analyzed. The risk score was based on cataract density, previous vitrectomy, presence of phacodonesis, small pupil, extreme axial length (> 30mm or < 21.5mm) or abnormal axial length (26-30mm), shallow anterior chamber (< 2.5mm), poor patient cooperation, oral alpha-1 blocker use, diabetic retinopathy (DR), Fuchs endothelial dystrophy, and having one functioning eye. This study focused on the correlation of risk scores with residents' surgical experience and surgical outcomes. As residents gained experience, surgeries on patients with at least one risk factor increased from 54% (first year) to 75% (second year; p < 0.001) and fluctuated between 75%, 82%, and 77% (third, fourth, and fifth years, respectively), with initial preoperative CDVA declining progressively. Despite handling more complex cases over time, the percentage of intraoperative complications per patient decreased with each year of residents' experience (17%, 13%, 11%, 17%, 6%; respectively). Patients without any risk factor had higher postoperative CDVA than those with one or more risk factors (mean ± standard deviation [SD] in logMAR, 0.16 ± 0.26 vs. 0.27 ± 0.35; p < 0.001) and a higher percentage of CDVA improvement (63% vs. 57%, p = 0.016). The use of a preoperative risk assessment scoring system to allocate surgeries to residents at varying experience levels may reduce the risk for surgical complications, thereby ensuring patient safety and providing residents with a gradual learning experience.

Epithelial ingrowth in descemet membrane endothelial keratoplasty associated with vitreous loss

BackgroundEpithelial ingrowth is a rare but potentially sight-threatening complication caused by the invasion of corneal or conjunctival epithelial cells into the eye during ocular surgeries. DMEK is emerging as a widely used surgery for endothelial keratoplasty with its improved safety profile. We describe a case of epithelial ingrowth in the graft-host interface after uneventful DMEK associated with vitreous prolapse in the anterior chamber.Case presentationAn 81-year-old female with Fuchs endothelial dystrophy underwent DMEK for corneal decompensation following cataract surgery. During the DMEK procedure, vitreous prolapse was observed around the intraocular lens (IOL). Her early postoperative course was unremarkable, but a dense paracentral interface opacity was observed during the 3-month follow-up. The area of epithelial ingrowth was imaged with optical coherence tomography (OCT) as a uniform nodule with a discrete increase in interface hyperreflectivity. A low-energy YAG laser was applied to remove the opacity. She maintained good vision and clear cornea without reoccurrence after treatment.ConclusionsWe propose that, in addition to the introduction of epithelial cells during surgery, vitreous retention in the anterior chamber may be a risk factor by providing a scaffold that potentially aggravates epithelial ingrowth in DMEK. Our case demonstrated that early YAG intervention may disrupt interface epithelial cell growth, and the transmitted laser energy may fragment the scaffold vitreous noninvasively.

Deep learning for detection of Fuchs endothelial dystrophy from widefield specular microscopy imaging: a pilotstudy

BackgroundTo describe the diagnostic performance of a deep learning (DL) algorithm in detecting Fuchs endothelial corneal dystrophy (FECD) based on specular microscopy (SM) and to reliably detect widefield peripheral SM images with an endothelial cell density (ECD) > 1000 cells/mm2.MethodsFive hundred and forty-seven subjects had SM imaging performed for the central cornea endothelium. One hundred and seventy-three images had FECD, while 602 images had other diagnoses. Using fivefold cross-validation on the dataset containing 775 central SM images combined with ECD, coefficient of variation (CV) and hexagonal endothelial cell ratio (HEX), the first DL model was trained to discriminate FECD from other images and was further tested on an external set of 180 images. In eyes with FECD, a separate DL model was trained with 753 central/paracentral SM images to detect SM with ECD > 1000 cells/mm2 and tested on 557 peripheral SM images. Area under curve (AUC), sensitivity and specificity were evaluated.ResultsThe first model achieved an AUC of 0.96 with 0.91 sensitivity and 0.91 specificity in detecting FECD from other images. With an external validation set, the model achieved an AUC of 0.77, with a sensitivity of 0.69 and specificity of 0.68 in differentiating FECD from other diagnoses. The second model achieved an AUC of 0.88 with 0.79 sensitivity and 0.78 specificity in detecting peripheral SM images with ECD > 1000 cells/mm2.ConclusionsOur pilot study developed a DL model that could reliably detect FECD from other SM images and identify widefield SM images with ECD > 1000 cells/mm2 in eyes with FECD. This could be the foundation for future DL models to track progression of eyes with FECD and identify candidates suitable for therapies such as Descemet stripping only.

Donor Characteristics in Graft Detachment after Posterior Lamellar Keratoplasty for Fuchs Endothelial Dystrophy and Bullous Keratopathy.

Background: Descemet Membrane Endothelial Keratoplasty (DMEK) has been widely adopted to treat Fuchs endothelial dystrophy (FED) and Bullous keratopathy (BK). Graft detachment (GD) is one of the common earliest post-operatory complications, and it is usually recovered by Air Rebubbling (ARB). Methods: Retrospectively, we investigated predictive factors related to GD between January 2016 and March 2020, a pre-COVID era, in 72 patients, 72 eyes, and their donors' lamellar characteristics, focusing on donor's cause of death. The patients were divided according to the posterior lamellar keratoplasty technique adopted. Results: GD and consequent ARB were most common but not significantly prevalent in DMEK (p = 0.11). It was more common in FED for both surgical approaches. Only in BK treated with DSAEK were host steeper mean astigmatism (p = 0.03) and donors with smaller graft pre-cut diameters (p = 0.02) less likely to be related to GD. Regarding donor's cause of death, only cardiovascular accident could be related to GD in BK treated with DMEK (p = 0.04). Conclusions: Our study shows that the conventional match between pathology and corneal lenticule is not sufficient to prevent ARB. Donor's cause of death can impair graft and host attachment. In particular, cardiovascular death may impair the efficiency of donors' endothelial cells, inducing GD after DMEK in BK.

In vivo confocal microscopy findings after Descemet stripping only with and without topical ripasudil supplementation in Fuchs endothelial dystrophy

PurposeTo report corneal epithelial and corneal endothelial cell (CEC) changes following Descemet stripping only (DSO) with and without topical ripasudil using in vivo confocal microscopy (IVCM). MethodsProspective interventional case series of patients who underwent DSO for Fuchs endothelial dystrophy with or without postoperative topical ripasudil (4%, 6 times per day). Patients underwent IVCM (ConfoScan 3; NIDEK Technologies, Padova, Italy) at baseline, monthly until corneal clearance, and then every 6 months. En face images were obtained of the epithelium, anterior and posterior corneal stroma, and endothelium of the central and superior cornea. The epithelial and endothelial layer images were evaluated qualitatively. ResultsIVCM imaging was obtained from 34 patients, 26 (76%) of whom were supplemented with ripasudil and 8 (24%) of whom were not. Two eyes (6%) did not clear and required a keratoplasty. IVCM confirmed epithelial and endothelial cell morphology changes and reestablishment of a CEC mosaic. Hyperreflective nuclei, pleomorphism, multinucleated cells, and pseudoguttae were identified within the descemetorhexis. In patients on ripasudil, epithelial cells demonstrated transition from stratified squamous to spindle cell shape in regions of ripasudil-induced honeycomb edema. Migrating cells adopted an amoeboid shape and cytoplasm elongation when crossing to central stroma. Transient epithelial cell morphology changes and endothelial cell amoeboid shape changes appear to be uniquely associated with ripasudil. Rarely, figures were noted in both ripasudil-treated and non-ripasudil-treated corneas that resembled mitotic bodies. ConclusionsCECs display a range of adaptive mechanisms during healing to re-form the endothelial mosaic following DSO. Ripasudil administration appears to induce unique epithelial and endothelial cell changes.

Enhanced Monofocal Intraocular Lenses in Fuchs' Endothelial Dystrophy Patients: Results from Triple Descemet Membrane Endothelial Keratoplasty Procedure.

Descemet membrane endothelial keratoplasty (DMEK) is currently regarded as the most effective surgical procedure for addressing Fuchs Endothelial Corneal Dystrophy (FECD), frequently performed in conjunction with cataract surgery. In this retrospective study, we present a comparison of visual performance, clinical outcomes, and optical quality between two types of monofocal Intraocular Lenses (IOLs): one standard and one enhanced intermediate vision model, implanted in patients who underwent combined phacoemulsification and DMEK surgery. This single center comparative retrospective study was conducted at the Eye Clinic of the University of Florence (Italy) and included a total of 48 eyes of 48 patients affected by FECD and cataract. All patients underwent combined DMEK with phacoemulsification procedures. The patients' data were analyzed and divided into two groups: one group (standard group) consisted of 24 eyes that underwent phaco-DMEK with implantation of a monofocal IOL, and the second group (enhanced monofocal group) included 24 eyes that underwent phaco-DMEK with implantation of an enhanced monofocal IOL. In both groups, the following monocular visual outcomes were evaluated 6 months after surgery: Uncorrected Distance Visual Acuity (UDVA) and Best-Corrected Distance Visual Acuity (BCDVA) at 4 mts; Uncorrected Intermediate Visual Acuity (UIVA), Distance-Corrected Intermediate Visual Acuity (DCIVA) at 66 cm; Uncorrected Near Visual Acuity (UNVA) and Best Corrected Near Visual Acuity (BCNVA). Monocular defocus curves were also assessed. Furthermore, optical quality in terms of Contrast Sensitivity (CS) in photopic conditions, Higher-Order Aberrations (HOAs) at a pupil size of 5 mm. Modulation Transfer Function (MTF), Objective Scatter Index (OSI), and Strehl ratio, were also analyzed. A Patient-Reported Spectacle Independence Questionnaire was revised to evaluate spectacle independence outcomes. the two groups did not exhibit statistically significant differences in terms of UDVA, BCDVA, UNVA and BCNVA, photopic CS, HOAs, OSI, Strehl ratio, and MTF. However, in the phaco-DMEK enhanced monofocal IOL group, significantly better results were observed in terms of UIVA and DCIVA as well as a different defocus curve profile at 1.50 D, providing better defocus results at intermediate distance compared with the ZCB00 IOL. In our study, we found that enhanced monofocal lens performed favorable visual outcomes, even in cases of FECD, compared to standard monofocal IOLs. Comparable optical quality observed in the Eyhance group could allow surgeons to consider these lenses as a viable option for selected patients with FECD.

Re-descemet membrane endothelial keratoplasty (DMEK) with preservation of the original graft after free roll in anterior chamber: A case report

IntroductionLamellar keratoplasties have had a great impact in the management of corneal edema due to endothelial dysfunction. Minimally invasive transplant techniques such as Descemet Membrane Endothelial Keratoplasty (DMEK) have helped to reduce the morbidity involved in performing penetrating keratoplasty in this type of patient. Even so, these are complex techniques that are not free of complications and require a long line of surgical learning and an even more demanding experience in postoperative management. Clinical caseAn 89-year-old woman suffering from Fuchs endothelial dystrophy and undergoing combined cataract and DMEK surgery presented stromal edema predominantly inferior and sectoral detachment of the graft 24 h after the intervention. After re-bubbling in consultations and 4 days later, the graft was observed rolled and free in the anterior chamber.She underwent re-DMEK with preservation of the original graft after 24 h, with de-epithelialization to optimize visualization. The graft was stained with trypan blue and the posterior stroma was protected with air. The graft was reimplanted under intraocular maneuvers and with an air bubble.24 h after surgery, the adhered graft was observed, with a great decrease in stromal edema. One month later, the patient had a clear cornea, persistent complete graft adhesion, and visual acuity of 0.9. ConclusionThe discovery of free roll in the anterior chamber after DMEK surgery constitutes the most complex form of graft detachment. Corneal edema as well as the arrangement of the different intraocular structures are conditions to be considered for the surgical resolution of this complication. In many cases, surgical repositioning of the graft is feasible, which means saving costs without the need to use new donor corneal tissues.

How Would Nature See Our Corneal Triumphs? The LXXIX Edward Jackson Lecture

To describe discrepancies between clinical observation and current teachings in corneal endothelial disease, particularly in Fuchs endothelial dystrophy and its potential association with primary open angle glaucoma. Perspective. A perspective is presented on Fuchs dystrophy, a disorder that commonly presents with a compromised endothelium but minimal stromal edema, indicating that the corneal imbibition pressure is relatively "too high." The discrepancy between the relative lack of stromal edema in the absence of an endothelial cell layer cannot be explained by the current theories involving a circulatory pumping mechanism over the endothelial cell layer, but may point to the following: (1) secondary involvement of the corneal endothelium in Fuchs dystrophy; (2) separate hydration systems for maintaining the imbibition pressure (vertical static hydration) and corneal nutrition (horizontal dynamic hydration); (3) the cornea as net contributor of aqueous humor; (4) a close relationship between the corneal imbibition and intraocular pressure, with potentially a shared regulatory system; and (5) a potential steroid-type hormone dependency of this regulatory system. Clinical observation shows that the stromal imbibition pressure is "too high" in Fuchs endothelial dystrophy, indicating that it may not primarily be an endothelial disease, but a type of "corneal glaucoma."

Prevalence of tomographic features associated with subclinical oedema in Fuchs dystrophy across three commercially available corneal tomographers

Aims/Purpose: Specific tomographic alterations suggestive for subclinical oedema have a known impact on FED prognosis. Here, we compare the prevalence of tomographic alterations associated with subclinical oedema in patients affected by Fuchs Endothelial Dystrophy (FED) imaged with corneal tomographers employing three different technologies.Methods: Patients with a clinical diagnosis of FED referred to the cornea service underwent tomography with 3 different devices: the Pentacam Scheimpflung camera (Oculus, Germany), the Casia2 AS‐OCT (Tomey, Japan), and the Precisio 2 blue‐light slit‐scanning tomographer (IVIS, Italy). All patients had confirmed corneal guttae at slit‐lamp examination. Subjects were classified into FED with no oedema, FED with subclinical oedema, and FED with clinical oedema according to a validated classification based on pachymetric and posterior elevation maps appearance on the Scheimpflung camera. The prevalence of these features was compared across the 3 devices, then two experienced ophthalmologists (M.A., M.L.P.) assigned a 0–3 score according to their evidence. A mixed‐effects binomial model estimated Odds Ratios (OR) for the scores of the 3 devices.Results: A total of 30 eyes were included: 7 eyes presented with clinically defined oedema, 18 eyes with no clinical oedema but tomographic features suggestive of subclinical oedema, and 5 eyes with no oedema and no tomographic alterations. The prevalence of Loss of parallel isopachs, Displacement of thinnest point, and Focal posterior depression did not differ between devices. However, identification of Loss of parallel isopachs was most evident on Precisio 2 compared to Pentacam (OR 9.6, p = 0.007), and the Displacement of thinnest point was most evident on Precisio 2 compared to both Pentacam and Casia2 (OR 6.9, p = 0.01 and OR 15.1, p = 0.005). 3 eyes showed alterations only on Precisio 2, one of which was later scheduled for DMEK.Conclusions: Scheimpflung camera, AS‐OCT, and blue‐light slit‐scanning based tomographers were all able to detect tomographic changes in FED. Nevertheless, our results suggest that the blue laser, slit‐scanning tomographer might be able to detect earlier, and delineate better, subclinical changes in FED.

Is it really keratoconus ‐ topographic mimicry

Aims/Purpose: The aim of this case series is to present eyes with topographic keratoconus configuration, but in which objectifiable no keratoconus exists and thus a so‐called pseudo‐keratoconus is present.Methods: Inclusion criteria were a topographic classification of the cornea as keratoconus by Scheimpflug imaging using the topographic keratoconus classification TKC and a typical elevation data profile with irregular astigmatism and slope (= Ansteilung) of the cornea. Clinical image by slit lamp examination, best‐corrected visual acuity and Scheimpflug tomography of the anterior segment of the eye (Pentacam®, OCULUS, Wetzlar, Germany) were analysed.Results: In our case series, 33 eyes of 23 patients were included. The mean age was 51 (±16) years and the ratio of females to males was balanced. The mean Kmax was 51.1 (±7.1) dioptres. The mean corneal thickness at the thinnest point was 517 (±80) μm. The best‐corrected decimal visual acuity was 0.47 (±0.27). The study eyes were divided into 3 groups according to the underlying cause of the topographic changes. One group included corneal diseases with inferior slope in topography (corneal scar n = 9, Map‐Dot‐Fingerprint dystrophy n = 6, Fuchs endothelial dystrophy n = 5, vortex keratopathy n = 2). The second group had a superior corneal slope that could be interpreted as a superior keratoconus configuration (Map‐Dot‐Fingerprint dystrophy n = 5, irregular astigmatism without other corneal pathology n = 2, Salzmann corneal degeneration n = 1, corneal scar n = 1). The third group included eyes with postoperative newly occurring keratoconus configuration after phototherapeutic keratectomy (n = 2).Conclusions: This case series shows that different corneal pathologies can imitate a topographic keratoconus configuration. The identification – not least at the slit lamp – and differentiation of these pathologies from keratoconus are important in daily practice with regard to counselling of the patients and further treatment.

Effect of antiglaucomatous eye drops on corneal endothelium

First choice therapy for reducing the intraocular pressure in context of glaucoma remains the applications of eye drops. Longterm exposure to topical therapy can clearly have an impact on the ocular surface, but as the medications penetrate through the cornea and are present in humour aqueous, also on all other layers of cornea, including corneal endothelium. In general, none of the medications from the standard pharmacological groups influences significantly an otherwise healthy corneal endothelium in an eye with glaucoma or ocular hypertension – be it in terms of central corneal thickness, be it in terms of endothelial cell density and morphology, be it for beta blockers, carbonic anhydrase inhibitors, pilocarpine, alpha2 agonists or prostaglandin analogues. The situation changes in diseased corneas, such as in Fuchs endothelial dystrophy, where topically applied carbonic anhydrase inhibitors can lead to increase in corneal thickness. Benzalkonium chloride has been proven toxic for corneal endothelial cells in vitro. However, in the daily practice and under real life circumstances, it is from the specific point of view on the corneal endothelium still not clear whether using non‐preserved topical glaucoma medications is an absolute imperative. One separate topic here is also a group of Rho‐kinase inhibiting topical medications. Apart from new mechanisms of action for reducing the intraocular pressure, this group of medications has also a direct influence on the corneal structures – from cornea verticillata on the epithelium corneal level, to mobilizing peripheral endothelial corneal cells as a possible therapeutic path for Fuchs endothelial dystrophy. One part of the lecture will address also these issues.

Mediators of Visual Acuity in Descemet Membrane Endothelial Keratoplasty and Ultrathin Descemet Stripping Automated Endothelial Keratoplasty.

The aim of this study was to investigate mediators of visual acuity in ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) compared with Descemet membrane endothelial keratoplasty (DMEK). This was a prespecified secondary analysis of the Descemet Endothelial Thickness Comparison Trial, a prospective, randomized controlled trial comparing UT-DSAEK with DMEK. Subjects with Fuchs endothelial dystrophy or pseudophakic bullous keratopathy presenting to 2 academic centers were enrolled and randomized to either UT-DSAEK (n = 25 eyes) or DMEK (n = 25 eyes). Higher order aberrations (HOAs) and corneal densitometry were measured with Pentacam Scheimpflug imaging at 3, 6, 12, and 24 months. The posterior corneal surface at the 6.0-mm optical zone had significantly less total HOAs ( P <0.001) in the DMEK group compared with UT-DSAEK at 24 months. Anterior and posterior corneal densitometry improved from baseline to 24 months for both UT-DSAEK and DMEK, but there was no significant difference between the 2 groups. Corneal densitometry and posterior HOAs were both associated with best-corrected visual acuity ( P <0.05). DMEK had 1.3 logarithm of the minimum angle of resolution better visual acuity compared with UT-DSAEK at 24 months. Approximately 64% of this effect was mediated through posterior HOAs, whereas none was mediated through anterior HOAs or densitometry. Decreased posterior HOAs mediate better visual acuity and account for improved vision after DMEK compared with UT-DSAEK. Corneal light scatter as measured by densitometry is similar between UT-DSAEK and DMEK, indicating that the increased thickness and stromal-stromal interface in UT-DSAEK do not significantly affect visual acuity.

Translation and validation of the Visual Function and Corneal Health Status (V-FUCHS) questionnaire into Spanish language

PurposeTo translate and validate the V-FUCHS questionnaire into Spanish in a population of patients with Fuchs endothelial dystrophy (DEF). MethodsThe V-FUCHS consists of 15 short, easily understandable questions that assess visual aspects of quality of life in patients with DEF, which can be gathered into a group of seven that assess the "Visual Difficulty" factor and another group of eight that assess the “Glare Factor”. For the translation and cultural adaptation, the standardized norms for this process were followed, among other phases, a translation, a back-translation and an application in patients with DEF. ResultsIn the first phase, consensus was reached on the Spanish translation of the V-FUCHS. Subsequently, 25 patients were included to carry out the pre-test phase with the aim of assessing the applicability and feasibility of the test. The score obtained a minimum value of -0.88 and a maximum value of +2.44, according to the Rasch probabilistic scale. The mean value obtained from the Visual Difficulty factor was 0.61 (±0.71), while the mean for the Glare Factor was 0.41 (±0.51). ConclusionThe validation of the V-FUCHS questionnaire, after its translation and adaptation into Spanish, proved to be a useful tool for assessing the visual quality of patients with DEF. Patients with a more advanced stage of the disease presented a greater severity in the test result. Likewise, the Glare Factor (Glare) correlates better with the pachymetric increase than with the visual acuity of the patient.