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

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

Splenectomy as a Risk Factor for Graft Rejection Following Endothelial Transplantation: Retrospective Study.

BACKGROUND: Anterior chamber-associated immune deviation (ACAID) is an active immunotolerance mechanism, which is induced by placing antigen into the anterior eye chamber as long as a major surgical trauma is avoided. For this reason, ACAID may be a major contributor to the favorable immunologic outcomes in Descemet membrane endothelial keratoplasty (DMEK). Rodent models have demonstrated the importance of a functional spleen for the development of an ACAID. OBJECTIVE: This study aimed to investigate whether splenectomy leads to increased rejection rates after DMEK in humans. METHODS: A retrospective evaluation was conducted on the course following DMEK at the Eye Center, Medical Center, University of Freiburg, for patients with a self-reported history of splenectomy compared to patients without this condition. Potential study patients were contacted by mail. A questionnaire to self-report splenectomy and the time thereof was sent out. The medical records of all consenting patients at the Eye Center were reviewed for graft survival and immune reactions. RESULTS: We asked 1818 patients after DMEK to report their history of splenectomy. A total of 1340 patients responded and were included in the study. Of these 1340 patients, 16 (1.2%) reported a history of splenectomy (ie, 26 DMEKs, with 10 patients being transplanted in both eyes and 6 patients being transplanted in 1 eye; median age at surgery 73.7, range 66.7-76.1 y). The remaining patients (1324 patients, ie, 1941 eyes) served as controls, with 1941 DMEKs (median age at surgery 71.5, range 64.1-77.2 y). Five (19%) out of the 26 eyes from the splenectomy group required a second transplant due to dislocation (n=2.8%), failure (n=2.8%), and rejection (n=1.4%). Kaplan-Meier analysis revealed no relevant difference compared with controls. CONCLUSIONS: Our results suggest that splenectomy has no major effect on the outcome following DMEK. Subsequent, ACAID may not be the main reason for the favorable immunological outcomes in DMEK, or the camero-splenic axis may be subordinate in humans. However, we only included 16 patients who underwent splenectomy, so it might be possible that we missed a minor effect.

Busin Glide-Assisted Pull-Through Insertion of Artificial Corneal Endothelium (EndoArt).

Background: Currently, the push-in technique through the corneal tunnel using a blunt-tip spatula is used to insert an artificial corneal endothelium (EndoArt) into the anterior chamber (AC). The device is useful for patients with bullous keratopathy; however, it may be difficult to manipulate the very thin implant through hazy cornea. Unlike DMEK graft, it cannot be stained and the F-mark is faint. So, visualizing and orienting the implant is a real challenge especially through a hazy cornea and inadequate AC visualization. Therefore, alternative EndoArt implantation techniques are needed in patients with advanced endothelial dysfunction to avoid complications. Purpose: To report an alternative technique for EndoArt implantation using a Busin glide. Technique: The EndoArt was loaded onto the Busin glide with the concave side of the EndoArt facing upward and was then pulled/pushed into the Busin glide opening. After the Descemet's membrane and endothelium were detached and removed in a circular fashion in a patient with advanced corneal endothelial decompensation, the Busin glide was inserted into the corneal incision, and the EndoArt was slowly pulled into the AC using retractor forceps. Finally, the air was injected into the AC. Conclusion: The Busin glide-assisted pull-through technique smoothly and securely inserted the EndoArt into the AC without upside-down attachment. This alternative technique can be useful for patients with a history of repeat intraocular surgeries or trauma with severe corneal edema to avoid potential complications such as epithelial implantation cysts or downgrowth.

Comparison of rebubbling rate between preloaded endothelium-in and preloaded no-touch endothelium-out Descemet membrane endothelial keratoplasty transplantation.

BACKGROUND: To compare the difference in rebubbling rates between patients undergoing Descemet membrane endothelial keratoplasty (DMEK) with endothelium-in using a standard IOL cartridge and those with endothelium-out DMEK utilizing a no-touch technique with borosilicate glass cartridge transplantation. METHODS: This retrospective study included all eyes that underwent preloaded endothelium-in or endothelium-out DMEK transplantation from June 2019 to December 2023 at the Hanusch Hospital, Vienna, Austria. All DMEKs were harvested, prepared and preloaded at the European Eye Bank of Venice, Italy. DMEK surgeries were done by one experienced surgeon and the procedure was completed by air tamponade of the anterior chamber. RESULTS: Overall, 32 eyes each of 31 endothelium-out patients and of 29 endothelium-in patients were included. 32 preloaded endothelium-in procedures were followed by 32 preloaded endothelium-out procedures. Rebubbling rate for endothelium-in was 15/32 (47%) and for endothelium-out was 7/25 (28%) (p = 0.035, Pearson's chi-squared test). Donor age was the most important variable for rebubbling in a random forest algorithm model (ROC: 0.69). CONCLUSIONS: Rebubbling rate in endothelium-out DMEK was less than two-thirds compared to endothelium-in DMEK favoring no-touch endothelium-out DMEK as the preferred technique of DMEK transplantation.

DMEK Surgery at a Tertiary Hospital in Sweden. Results and Complication Risks.

Purpose: This study reports clinical outcomes up to 6 years after Descemet's membrane endothelial keratoplasty (DMEK) performed at the Department of Ophthalmology, Örebro University Hospital, Örebro, Sweden. Methods: The study has a cross-sectional and case series design. Inclusion criteria were all DMEK-operated eyes during 2013-2018 until repeat keratoplasty. Results: Altogether 162 eyes from 120 patients were enrolled. Among eyes without preoperative comorbidities, examined 1-6 years after DMEK, 85.8% achieved visual acuity of 0.1 logMAR or better. The median endothelial cell density (ECD) loss was 27% in a cohort of eyes examined 1-2 years post-DMEK, 31% at 2-3 years, 42% at 3-4 years, and > 60% at 4-6 years post-DMEK. ECD at the examination timepoint was correlated with donor ECD (as expected) and time since surgery. Conclusion: The results from DMEK surgeries in Örebro, Sweden, are promising. Further studies with even longer follow-up are needed to evaluate graft sustainability.

Descemet's membrane endothelial keratoplasty rejection after SARS-COV2 infection or vaccination: 2-year retrospective study.

PURPOSE: To assess the incidence of Descemet's membrane endothelial keratoplasty (DMEK) rejection potentially associated with coronavirus disease 2019 (COVID-19) infection or vaccination, and its association with known rejection risk factors during the first two years of the pandemic. METHODS: This retrospective study included patients with DMEK rejection between January 2020 and December 2021. Diagnostic criteria were based on symptoms, visual acuity, and other clinical assessments. Risk factors for graft rejection were considered, and a telephone survey was conducted to identify possible preceding COVID-19 infection or vaccination. RESULTS: Of 58 patients, 44 were included. Six patients (14%) reported COVID-19 infection, with one immediate endothelial graft rejection (EGR) post-infection. After vaccine availability, 13 of 36 patients had EGR at an average of 2.7 months post-vaccination. Five (38%) had immediate EGR following vaccination, four of which had concomitant risk factors for rejection. CONCLUSION: Although the risk of endothelial graft rejection (EGR) associated with COVID-19 infection or vaccination appears to be extremely low, there may be a causative relationship, especially in patients with pre-existing risk factors for EGR. A temporary increase in anti-rejection treatment following COVID-19 infection or vaccination is recommended, especially in patients with pre-existing risk factors, along with closer monitoring during the subsequent 4 to 8 weeks.

Re-Descemet Membrane Endothelial Keratoplasty (DMEK) con preservación del injerto original tras free roll en cámara anterior: a propósito de un caso / Re-descemet membrane endothelial keratoplasty (DMEK) with preservation of the original graft after free-roll in the anterior chamber: a case report

Introducción: Las queratoplastias lamelares han supuesto un gran impacto en el manejo del edema corneal por disfunción endotelial. Las técnicas de trasplante mínimamente invasivo como la Descemet Membrane Endothelial Keratoplasty (DMEK) han permitido reducir la morbilidad que suponía la realización de una queratoplastia penetrante en este tipo de pacientes. Aun así, se trata de técnicas complejas que no están exentas de complicaciones, y que requieren una larga línea de aprendizaje quirúrgico y una aún más exigente experiencia en el manejo postoperatorio.Caso clínicoUna mujer de 89 años afecta de distrofia endotelial de Fuchs e intervenida de cirugía combinada de catarata y DMEK, presentó a las 24h de la intervención un edema estromal de predominio inferior y un despegamiento sectorial del injerto. Tras un re-bubbling en consultas y 4 días más tarde, se observó el injerto enrollado y libre en cámara anterior.Se intervino de re-DMEK con preservación del injerto original tras 24h, con desepitelización para optimizar la visualización. Se tiñó el injerto con azul tripán y se protegió el estroma posterior con aire. Se reimplantó el injerto bajo maniobras intraoculares y con burbuja de aire.A las 24h de la cirugía se observó el injerto adherido, con una gran disminución del edema estromal. Un mes después, la paciente presentaba una córnea transparente, una persistente adhesión completa del injerto y una agudeza visual de 0,9.ConclusiónEl hallazgo del free roll en cámara anterior tras cirugía de DMEK constituye la forma más compleja de despegamiento del injerto. El edema corneal, así como la disposición de las diferentes estructuras intraoculares son condicionantes a tener en cuenta para la resolución quirúrgica de esta complicación. En muchos casos el reposicionamiento quirúrgico del injerto es factible, hecho que implica ahorrar costes sin necesidad de utilizar nuevos tejidos corneales donantes. (AU)

Introduction: Lamellar 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 24h 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 24h, 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.Twenty four hours 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. (AU)

Phakic anterior chamber intraocular lens removal with simultaneous posterior chamber phakic intraocular lens implantation and Descemet membrane endothelial keratoplasty.

The purpose of this study was to describe a case and clinical course of simultaneous anterior chamber phakic intraocular lens (AC-pIOL) removal, implantation of a posterior chamber phakic intraocular implantable collamer lens (ICL), and Descemet membrane endothelial keratoplasty (DMEK). This was a case report of a 44-year-old male with a unilateral decompensated cornea from a displaced Duet-Kelman lens on his left eye that underwent pIOL extraction and implantation of a posterior chamber phakic intraocular ICL and simultaneous DMEK. After 6 months, the cornea of the left eye had regained clarity, the Descemet membrane was graft stable, and the ICL implanted was centered with good vault. Postoperative anisometropia was avoided. There was no development of cataracts or other complications. The simultaneous pIOL extraction, ICL implantation, and DMEK in our case showed good results with full restoration of anterior segment anatomy and return of transparency of the cornea. The current case shows the feasibility of the simultaneous approach instead of sequential as an alternative for patients with endothelial disease associated with AC pIOLs, restoring vision and anatomy and also avoiding postoperative anisometropia.

Effects of graft detachment on the central corneal thickness after uncomplicated Descemet membrane endothelial keratoplasty.

PURPOSE: To determine if early central corneal thickness (CCT) and best-corrected visual acuity (BCVA) changes indicate graft detachment after uncomplicated Descemet membrane endothelial keratoplasty (DMEK). METHODS: In this analysis of our prospectively collected ADDA registry data ( https://drks.de/search/de/trial/DRKS00027180 ), 45 pseudophakic eyes underwent DMEK surgery at the Department of Ophthalmology, RWTH Aachen University. Anterior segment optical coherence tomography (AS-OCT), the presence of stromal ripples on the posterior corneal surface, and BCVA measurements were assessed prior to, 1 day, 1 week, 1 month, and 6 months after surgery. RESULTS: Eyes were categorized into three groups: no graft detachment (group 1) (20/45; 44.4%), < 1/3 graft detachment (group 2) (14/45; 31.1%), ≥ 1/3 graft detachment followed by rebubbling (group 3) (11/45; 24.4%). Eyes in group 3 had a greater CCT prior to (746.8 ± 95.8 µm vs. 665.0 ± 74.4 µm, P = 0.041), and 1 week (666.8 ± 119.5 µm vs. 556.5 ± 56.8 µm, P = 0.001) after DMEK compared to group 1. By 1 month, CCT in all groups aligned. Comparing prior to and 1 week after DMEK, none of the eyes in group 1 had an increase in CCT, while the CCT increased in 25.0% of eyes in group 2 and 22.2% in group 3. In group 1, 90.0% had a CCT of < 600 µm 1 week after DMEK, compared to only 50.0% in group 2 and 36.4% in group 3. In group 1, 90.0% (18/20) had an improved BCVA 1 week after DMEK, while in groups 2 and 3, 86.7% (12/14) and 18.2% (2/11) improved, respectively. One patient in group 3 showed posterior stromal ripples 1 day and 1 week after DMEK. CONCLUSION: If 1 week after uncomplicated DMEK CCT is < 600 µm and has decreased from before surgery, BCVA has improved, and there are no posterior stromal ripples, a graft detachment ≥ 1/3 and the need for rebubbling are very unlikely. In all other cases, meticulous slit-lamp and OCT inspection of the peripheral graft for detachments should be advised.

Fabrication of bioengineered corneal endothelial grafts using an allogeneic cornea-derived matrix.

Corneal endothelial keratoplasty has been the primary treatment method of endothelial decompensation, but it is often limited in clinical practice due to global shortage of donor cornea. Here, we explored using an ultra-thin allogeneic cornea-derived matrix (uACM) films as a substrate for constructing bioengineered corneal endothelial grafts. We evaluated the films' optical, mechanical, and structural properties, and measured the composition of the extracellular matrix. The uACM was an ultrathin and curved cornea-shaped film with favorable optical and mechanical properties. The fabrication process efficiently preserved corneal extracellular matrix composition and significantly decreased cellular components. Moreover, human corneal endothelial cells and rabbit corneal endothelial cells (RCECs) can adhere and grow on the uACM films with a positive expression of the corneal endothelial functional markers Na+/K+-ATPase and ZO-1. The successful transplantation of uACM with RCECs grafts into the rabbit model of endothelial dysfunction via Descemet membrane endothelial keratoplasty resulted in prompt restoration of corneal transparency and thickness. During the four-week follow-up period, the uACM with RCECs implanted eyes exhibited comparable corneal transparency, central corneal thickness, and endothelial cell count to that of the healthy rabbit. Histologic examination revealed that the grafts were successfully attached and integrated onto the posterior surface of the corneal stroma. The uACM achieved biomimetic reconstruction in terms of both composition and structure, and can be used to construct the bioengineered corneal endothelial grafts. These results indicate that constructing bioengineered corneal endothelial grafts from discarded human corneal tissues may pave the way for generating high-quality corneal endothelial grafts for transplantation.

Pediatric corneal transplantation: techniques, challenges, and outcomes.

Pediatric corneal transplant is a highly demanding and technically challenging procedure for the cornea surgeon in today's era. These cases pose unique challenges in clinical and surgical management. The indications of pediatric corneal transplant can be therapeutic, tectonic, optical, and cosmetic. Pediatric patients undergoing corneal transplants are at a high risk of graft infection, failure, rejection, dehiscence, and amblyopia due to young age, robust immune system, increased incidence of trauma, and compliance issues. The other factors contributing to graft failure can be allograft rejection, secondary glaucoma, corneal vascularization, multiple surgeries, vitreous prolapse, and lack of treatment compliance. A successful corneal transplant in children depends on meticulous preoperative evaluation, uneventful surgery, the expertise of a corneal surgeon, and regular and timely postoperative follow-up. Therapeutic and optical penetrating keratoplasty are the most commonly performed transplants in children. However, with the advancements in surgical technique and management protocol, the current focus has shifted toward lamellar keratoplasty. Lamellar keratoplasty offers early visual recovery and potentially fewer complications. Visual rehabilitation through corneal transplant in otherwise blind eyes can be a boon for the children. Recently, keratoprostheses have been promising in children with multiple graft failures. The current review gives insights into epidemiology, etiology, indications, clinical characteristics, investigations, management options, recent advances, and the future of pediatric corneal transplants. As surgical techniques continue to grow and comprehension of pediatric corneal transplants is improving, we can safeguard these eyes with the best possible anatomical and functional outcomes.

Epithelial ingrowth in descemet membrane endothelial keratoplasty associated with vitreous loss.

BACKGROUND: Epithelial 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 PRESENTATION: An 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. CONCLUSIONS: We 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.

Novel technique to improves graft unfolding in vitrectomized eyes during Descemet membrane endothelial keratoplasty.

INTRODUCTION: Descemet membrane endothelial keratoplasty (DMEK) is commonly used to treat endothelial pathologies in bicameral pseudophakic eyes with a normal depth of the anterior chamber. However, performing this procedure on eyes that have undergone vitrectomy carries a higher risk of complications. Therefore, this report presents a novel technique for improving the unfolding of a DMEK graft in a vitrectomized eye. PRESENTATION OF CASE: A 49-year-old man with a history of complicated cataract surgery one year prior was referred to our clinic with pseudophakic bullous keratopathy in his left eye. The surgery involved a posterior capsular rupture, anterior vitrectomy, and implantation of a sulcus three-piece intraocular lens. DMEK and anterior vitrectomy were performed. However, the conventional tap technique was unsuccessful in unfolding the DMEK graft, owing to intraoperative hypotony and an inability to flatten the anterior chamber. DISCUSSION: To minimize excessive manipulation of the donor tissue, a 27-gauge cannula attached to a 3-cc syringe was used. A cannula was introduced through paracentesis near the edge of an unfolded DMEK graft. We then created a suction force by pulling back the plunger while slowly moving the needle backward during the graft unfolding. The postoperative course was uneventful, with a clear and fully attached DMEK graft. CONCLUSIONS: This technique reduces the complexity of DMEK graft unfolding in vitrectomized eyes, enabling easier and more controlled unfolding. However, further research with larger patient populations is required to determine the clinical relevance of this method.

Hitting the refractive target in corneal endothelial transplantation triple procedures: A systematic review.

In phakic patients Descemet stripping automated endothelial keratoplasty (DSAEK) or Descemet membrane endothelial keratoplasty (DMEK) are frequently combined with phacoemulsification and intraocular lens (IOL) implantation (triple procedure). This surgery might cause a refractive shift difficult to predict. Early DMEK and DSAEK results have shown a tendency toward a hyperopic shift. Myopic postoperative refraction is typically intended to correct this postoperative refractive defect and to bring all eyes as close to emmetropia as possible. We sought to understand the mechanism underlying the hyperopization and to identify predictive factors for poorer refractive outcomes, the most suitable target refraction and IOL calculation methods in patients undergoing combined cataract extraction and lamellar endothelial corneal transplantation (DSAEK or DMEK) for endothelial dysfunctions. Of the 407 articles analyzed, only 18 were included in the analysis. A myopic target between -0.50 D and -0.75 was the most common (up to -1.50 for DSAEK triple procedures), even though no optimum target was found. Hyperopic surprises appeared more frequently in corneas that were flatter in the center than in the periphery (oblate posterior profile). Among the numerous IOL calculation formulas, there was no apparent preference.

Predictive factors for re-bubbling after DMEK: focus on the posterior corneal surface.

PURPOSE: To understand whether the preoperative morphology of the posterior corneal surface influences the rate of re-bubbling after Descemet membrane endothelial keratoplasty (DMEK). METHODS: After retrospectively analyzing the medical records of patients undergoing DMEK, in this multicentric cross-sectional study, we performed a binomial logistic regression analysis to assess significant predictors of re-bubbling and re-transplantation after surgery. Analyzed parameters included the preoperative diagnosis, anterior and posterior surface K1/K2, central corneal thickness, posterior Q value, and other posterior corneal surface parameters evaluated on the elevation maps produced by anterior segment optical coherence tomography. Results were stratified based on the surgeons' experience. RESULTS: We included 202 eyes of 202 patients with a mean age of 69.5 ± 12.4 years; 154 eyes were operated by a high-volume surgeon and 48 by one with less experience; 48 eyes (23.8%) underwent ≥ 1 re-bubbling and 14(6.9%) ≥ 1 re-transplantation. The presence of positive/less-negative posterior corneal irregularities and irregularities with greater absolute height had a significantly higher risk of re-bubbling in both the expert and less expert group (OR = 2.85 and 1.42, OR = 3.22 and 3.01, respectively, p < 0.05), whereas more negative posterior K1 and K2 were significant risk factors only in the former group (OR = 0.67 and 0.55, respectively, p < 0.05). Endothelial decompensation other than Fuchs and pseudophakic bullous keratopathy, more negative posterior Q values and smaller distances between center, and the highest/lowest posterior corneal surface irregularity correlated with an increased risk of graft failure (OR 1.23, 1.21, and 1.29, respectively, p < 0.05). CONCLUSION: Posterior corneal surface morphology significantly influences the risk of re-bubbling after DMEK.

Risk factors for early graft detachment requiring rebubbling in Descemet membrane endothelial keratoplasty with imported pre-cut donor tissues.

Graft detachment is a common and significant complication in Descemet membrane endothelial keratoplasty (DMEK). We investigated the risk factors of graft detachment requiring rebubbling after DMEK using imported pre-cut donor tissues. The medical records of 48 patients who underwent DMEK for Fuchs' endothelial dystrophy (FED) or bullous keratopathy (BK) at Seoul National University Hospital were retrospectively reviewed. Donor, recipient, and surgical factors were evaluated using univariate and multivariate logistic regression models. Graft detachment requiring rebubbling occurred in 17 (32.7%) eyes. The detachment group exhibited older recipient age (p = 0.006), higher prevalence of diabetes (p = 0.001), and a higher proportion of FED (65%, p = 0.003). Notably, the detachment group demonstrated a significantly lower postoperative 2-h intraocular pressure (IOP) (p = 0.002) and a greater proportion of eyes with IOP <20 mmHg (p < 0.001). Older recipient age (OR 1.08, 95% CI 1.02-1.17), diabetes (OR 23.8, 95% CI 2.61-217), FED surgical indication (OR 6.19, 95% CI 1.74-22.0), lower postoperative 2-h IOP (OR 1.21, 95% CI 1.06-1.38), and postoperative 2-h IOP <20 mmHg (OR 14.0, 95% CI 1.64-119) were associated with increased odds of graft detachment. According to multivariate logistic regression, lower postoperative 2-h IOP (OR 1.23, 95% CI 1.02-1.47) and postoperative 2-h IOP <20 mmHg (OR 25.1, 95% CI 1.05-602) increased the risk of graft detachment. Lower postoperative 2-h IOP, particularly below 20 mmHg, may increase the risk of graft detachment, and diabetes in recipients may pose a higher risk of graft detachment after DMEK.

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

INTRODUCTION: Lamellar 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 CASE: An 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. CONCLUSION: The 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.

Descemet Membrane Endothelial Keratoplasty after failed penetrating keratoplasty- case series and review of the literature.

BACKGROUND: This study aims to evaluate visual outcome, central corneal thickness, and re-bubbling rate in a cohort with undersized sequential Descemet Membrane Endothelial Keratoplasty (DMEK) due to endothelial graft decompensation following primary penetrating keratoplasty (PK). METHODS: All patients who received a sequential DMEK (n = 16) or triple DMEK (n = 2) after failed primary PK between November 2020 and June 2022 were retrospectively evaluated. Analyzed parameters were corrected distance visual acuity (CDVA), central corneal thickness (CCT), re-bubbling rate and graft survival. RESULTS: 18 eyes of 18 patients were included. All patients underwent a DMEK with undersized graft after failed PK(s). Mean time between the last PK and DMEK was 102 ± 82 weeks. Mean follow-up time was 8.9 ± 4.6 months. CDVA increased significantly from 1.12 ± 0.60 logMAR preoperatively to 0.64 ± 0.49 logMAR 6 weeks postoperatively (p = 0.013). Mean CCT decreased significantly from 807 ± 224 µm before to 573 ± 151 µm 6 weeks after DMEK (p = 0.003). Re-bubbling was necessary in eight eyes (44.4%) after a median time of 7 days. The 12-month Kaplan Meier survival was 66.7%. CONCLUSION: In case of endothelial graft decompensation without stromal scars after primary PK, a DMEK can be performed for selected patients who had satisfying CDVA before the endothelial decompensation. Prior to DMEK indication, an AS-OCT should routinely be performed to circularly search for posterior steps at the PK graft margin, as well as shortly after DMEK to exclude a detachment of the endothelial graft. All patients should be informed about a higher re-bubbling rate in comparison to primary DMEK.

Comparison of efficacy of three gases for anterior chamber tamponade in Descemet's membrane endothelial keratoplasty.

PURPOSE: To compare the efficacy of three different gases for intraocular tamponade: 100% air, 10% perfluoropropane (C3F8), and 10% sulfur hexafluoride (SF6), in Descemet's membrane endothelial keratoplasty (DMEK). MATERIALS AND METHODS: The medical records of 138 patients who underwent DMEK were reviewed retrospectively, with the primary outcome being the rebubbling rate in the first week following surgery. Other clinical outcomes, such as best-corrected visual acuity (BCVA), central corneal thickness (CCT), incidence of rebubbling after the first week, endothelial cell density (ECD), graft detachment, graft failure, pupillary block, and intraocular pressure (IOP) changes were also analyzed. RESULTS: Of the 138 patients, 57 were in group 1 (treated with air), 44 in group 2 (treated with 10% C3F8), and 37 in group 3 (treated with 10% SF6). Group 3 showed significantly lower rates of graft detachment and rebubbling compared to groups 1 and 2 (P<0.001). However, there was no significant difference in postoperative BCVA among the groups. At one year, the mean endothelial cell loss was 32% in group 1, 30% in group 2, and 33% in group 3 (P=0.715). One patient in group 1 experienced pupillary block and increased IOP, while there were no such occurrences in the other groups. There was no difference between the groups in terms of graft failure. CONCLUSION: The use of 10% SF6 in DMEK surgery may be a good option due to its efficacy in preventing graft detachment, low rebubbling rate, and potential for minimizing complications.

Cost-effectiveness of the ADVISE trial: An intraoperative OCT protocol in DMEK surgery.

The intraoperative optical coherence tomography (iOCT) is recently introduced in Descemet membrane endothelial keratoplasty (DMEK) surgery, which aims to increase clinical performance and surgery safety. However, the acquisition of this modality is a substantial investment. The objective of this paper is to report on the cost-effectiveness of an iOCT-protocol in DMEK surgery with the Advanced Visualization in Corneal Surgery Evaluation (ADVISE) trial. This cost-effectiveness analysis uses data 6 months postoperatively from the multicentre prospective randomized clinical ADVISE trial. Sixty-five patients were randomized to usual care (n = 33) or the iOCT-protocol (n = 32). Quality-Adjusted Life Years (EQ-5D-5L), Vision-related Quality of Life (NEI-VFQ-25) and self-administered resources questionnaires were administered. Main outcome is the incremental cost-effectiveness ratio (ICER) and sensitivity analyses. The iOCT protocol reports no statistical difference in ICER. For the usual care group compared with the iOCT protocol, respectively, the mean societal costs are €5027 compared with €4920 (Δ€107). The sensitivity analyses report the highest variability on time variables. This economic evaluation learned that there is no added value in quality of life or cost-effectiveness in using the iOCT protocol in DMEK surgery. The variability of cost variables depends on the characteristics of an eye clinic. The added value of iOCT could gain incrementally by increasing surgical efficiency, and aiding in surgical decision-making.