The progress and future of corneal endothelial transplantation.

Endothelial transplantation has recently been accepted worldwide, in the long history of corneal transplantation. The introduction of endothelial keratoplasty (Descemet stripping automated endothelial keratoplasty and Descemet membrane endothelial keratoplasty) has enabled us to expand the surgical indications owing to the low incidence of rejection and quick recovery of visual function. New technologies have been developed to ensure stable postoperative outcomes with a shorter learning curve, such as transplantation using cultured human endothelial cells and induced pluripotent stem cells (iPS) or new devices such as artificial endothelium. This review discusses the history and characteristics of corneal transplantation alongside new treatment options that may offer hope for patients with endothelial disease in the future.

A Case of Transparent Cornea Maintained after Removal of Dislocated Graft from Descemet's Stripping Automated Endothelial Keratoplasty.

Introduction: Corneal graft detachment is a major postoperative complication of Descemet's stripping automated endothelial keratoplasty (DSAEK). When a corneal graft becomes detached, corneal endothelial function generally fails, and repeat corneal transplantation is required. Herein, we report a rare case in which a transparent cornea was maintained after the removal of a dislocated DSAEK graft. Case Presentation: A 79-year-old woman with a residual lens cortex who had undergone cataract surgery was referred to our hospital. The cortex was removed, and bullous keratopathy progressed. Six months after the initial surgery, DSAEK was performed under topical anesthesia without any complications. Although the corneal graft had attached fairly well, it detached from the host cornea 3 weeks later. Two months after DSAEK, an air tamponade was used to treat the anterior chamber with single interrupted suturing; however, the graft detached again, except for the suture site. Because the detached cornea became cloudy in the anterior chamber, it was surgically removed 8 months after DSAEK. Accordingly, the host cornea transparency improved to a best-corrected visual acuity of 0.8 with a rigid gas permeable lens and a central corneal thickness of 580 µm. The corneal endothelial cell density was 995 cells/mm2. Conclusion: Removal of the corneal graft from the dislocated cloudy graft improved the visual acuity of this patient after DSAEK. The condition of the cornea should be carefully monitored after corneal endothelial transplantation, even after the graft has been dislocated.

Evaluating a Sustained-Release Dexamethasone Insert as Adjunctive Therapy for Inflammation and Pain Post-Corneal Transplantation.

Purpose: To assess the efficiency and safety of an intracanalicular dexamethasone insert (Dextenza, Ocular Therapeutix, Inc) supplemented with a reduced-frequency topical drop regimen in mitigating pain and inflammation post-penetrating keratoplasty (PKP), Descemet stripping endothelial keratoplasty (DSEK), and Descemet membrane endothelial keratoplasty (DMEK), compared to standard topical corticosteroid therapy. Patients and Methods: Eyes were categorized within the DSEK, DMEK, or PKP groups based on ocular characteristics and surgical indications. Randomized in a 1:1 ratio, the intervention group received Dextenza alongside a lowered drop frequency, while the control group followed a conventional drop protocol with no Dextenza. Primary outcomes included average pain scores and absence of anterior chamber cell and flare. Secondary outcomes included delayed re-epithelialization, corneal rejection episodes, instances of intraocular pressure (IOP) elevation >10mmHg above baseline, cystoid macular edema (CME) occurrence, and the necessity for steroid rescue. Results: The study included 30 eyes (10 PKP, 10 DSEK, 10 DMEK). Mean pain scores (0-100 scale; (0-39 = mild pain, 40-69 = moderate pain, 70-100 = severe pain) in the Dextenza group were 3.6 (PKP), 12 (DSEK), 8 (DMEK), compared to 1.2 (PKP), 0 (DSEK), and 4 (DMEK) in controls. PKP control (n=5): 1 delayed re-epithelialization, 1 IOP elevation, 2 CME. DSEK control (n=5): 1 corneal rejection, 1 IOP elevation, 1 CME. DMEK control (n=5): 1 IOP elevation, 1 CME. DMEK Dextenza (n=5): 1 delayed re-epithelialization, 1 CME. No cases required steroid rescue, and no cell or flare was observed one-week post-surgery. There were no statistically significant differences in pain, delayed re-epithelialization, IOP elevation, corneal rejection, or CME between the Dextenza and control groups regardless of the type of corneal transplantation performed. Conclusion: Dextenza, when combined with a lower-frequency drop regimen, demonstrates a safety profile comparable to that of a traditional higher-frequency drop protocol in terms of pain management and the adverse events explored in this study, potentially enhancing postoperative drop adherence.

Mechanism and treatment of secondary glaucoma after corneal transplantation: a review.

Corneal transplantation is a common treatment for corneal diseases. Secondary glaucoma after corneal transplantation is the second leading cause of failure of keratoplasty. This article reviews the mechanism and treatment of secondary glaucoma after corneal transplantation.

Subfoveal choroidal thickness increases after excimer laser-assisted penetrating keratoplasty but not after excimer laser-assisted deep anterior lamellar keratoplasty.

To evaluate the impact of excimer laser-assisted deep anterior lamellar keratoplasty (Exc-DALK) and excimer laser-assisted penetrating keratoplasty (Exc-PKP) on subfoveal choroidal thickness (SFCT) in eyes with advanced keratoconus. A retrospective comparative clinical study, which compares the outcomes of 24 eyes treated with Exc-DALK (G1) against matched group of 43 eyes treated with Exc-PKP (G2) at both 2 months (T1) and 2 years (T2) postoperatively. Main outcomes included best-corrected visual acuity (BCVA), central macular thickness (CMT), and SFCT. Preoperatively, there were no significant differences between both groups regarding BCVA, CMT or SFCT (p > 0.05). There were no significant differences between both groups regarding BCVA at both follow-ups (p > 0.05). There were no significant differences between both groups regarding CMT at both follow-ups (p > 0.05). SFCT was higher in G2 than G1 at both follow-ups (p < 0.01). Compared to preoperative SFCT, there were no significant changes in SFCT in G1 at both follow-ups (p > 0.05). In G2, SFCT increased significantly at T1 (p < 0.01) and did not differ significantly at T2 (p = 0.17). SFCT increased significantly after Exc-PKP but not after Exc-DALK, which might indicate that Exc-DALK affects the choroid less and thus could represent a less traumatic approach to ocular tissue than Exc-PKP.

Ochrobactrum anthropi infection following corneal transplantation -a case report and review of literature.

BACKGROUND: Ochrobactrum anthropi is widely distributed and primarily infects patients with compromised immune functions . Historically, O. anthropi has been considered to possess low toxicity and pathogenicity; however, recent studies suggest that it may in fact cause severe purulent infections. In this case study, we examine a case of O. anthropi infection following corneal transplantation, exploring the occurrence and outcomes of such post-operative infections. CASE PRESENTATION: A retrospective analysis of cases involved examinations, genetic testing for diagnosis, and subsequent treatment. In patients undergoing partial penetrating keratoplasty with a fungal corneal ulcer perforation, anterior chamber exudation and purulence were observed post-surgery. Despite antifungal treatment, genetic testing of the anterior chamber fluid and purulent material confirmed O. anthropi infection. The use of antimicrobial treatment specifically targeting O. anthropi was found to be effective in treating the infection. CONCLUSION: Inflammatory reactions following corneal transplantation should be should be monitored for the presence of other infections. Genetic testing has significant implications for clinical diagnosis and treatment.

Impact of an educational video in improving awareness of eye donation among non-medical health care workers in a tertiary health centre.

PURPOSE: To evaluate the impact of an educational video in improving awareness of eye donation among non-medical healthcare workers at a tertiary health centre. METHODS: A socio-behavioural study on knowledge and attitude towards eye donation was conducted among 373 non-medical healthcare workers through a printed semi-structured questionnaire before and after viewing a bilingual educational video. The responses were evaluated and scored. RESULTS: Pre-intervention, only 5.4% of the participants had adequate knowledge, which improved significantly to 71.6% after watching the video (P < .001). Respondents with elementary school education showed the greatest change in knowledge. Pre-intervention, 72.4% were willing to donate their eyes, which significantly increased to 89.5% after watching the video. Pre-intervention, 66.22% showed a "highly favourable" attitude, which improved to 97.86% after watching the video. CONCLUSION: The 25 min video about eye donation and eye banking significantly changed the participants' knowledge, willingness, and attitude. Hence, media-based (video) awareness platforms may be valuable for improving the general public's knowledge and attitude towards eye donation. This may help in enhancing the eye donation rate in the long term.

A Detailed Analysis of Individuals Having Graft Failure After Corneal Transplantation.

PURPOSE: To describe demographic and clinical characteristics of patients with graft failure after keratoplasty, determine the cause of graft failure and outcomes. METHODS: The charts of patients between 2008-2013 in the Cornea Service at Wills Eye Hospital with a history of a corneal transplant before the end of 2012 were retrospectively reviewed. Included were patients who had graft failure after corneal transplantation and had at least one year of follow-up after transplantation. Penetrating keratoplasty (PK) and Descemet's stripping endothelial keratoplasty (DSEK) patients were analyzed separately. RESULTS: A total of 186 eyes of 170 patients with graft failure after a PK (156) or DSEK (30) procedures were identified. The baseline characteristics included 100 female and 70 male patients with an age between 0 and 90 years (median 63 years). At the time of surgery, 38% had three or more systemic diseases and 68% were using three or more systemic medicines. Mean follow up time for PK was nearly four times of DSEK. Only 2 DSEK eyes (7%) underwent a 3rd DSEK graft, while 47 (30%) PK eyes underwent a 3rd PK and 15 (10%) PK eyes underwent more than three PK procedures. CONCLUSIONS: Most DSEK failures occurred in 1st year, while graft failure in PKs is scattered over years. Failure in DSEK is mostly due to graft or surgical risk factors but in PK mostly due to factors in the host. DSEK does not appear to be as affected by the patients' demographic and clinical characteristics as much as PK.

Unveiling the landscape of post-keratoplasty keratitis: a comprehensive epidemiological analysis in a tertiary center.

PURPOSE: The present study aimed to epidemiologically evaluate patients with infectious keratitis following corneal transplantation. METHODS: This retrospective study analyzed medical records of patients who underwent keratoplasty from March 2014 to March 2022 at a tertiary center. A total of seventy-five patients were evaluated. The data were classified based on culture results, the type of microorganisms involved, treatment requirements, and the type of primary keratoplasty performed. RESULTS: Seventy-five patients were evaluated in this study, with a mean age of 45.9 years (22-95 years). The mean duration between the first surgery and the incidence of infectious keratitis was 1.43 years, and most cases occurred in the first year (56.2%). Bacterial and fungal keratitis in 2.17%, 1.39%, and 1.26% of cases undergoing penetrating keratoplasty (PK), endothelial keratoplasty (EK), and anterior lamellar keratoplasty (ALK) occurred, respectively. Streptococcus viridans (9.3%) and Staphylococcus aureus (6.6%) had the highest prevalence. Across various smear and culture results (gram-positive, gram-negative, fungal, and negative culture), no significant differences were found in endophthalmitis rates (P = 0.797) and the necessity for tectonic grafts (P = 0.790). Similarly, the choice of surgical method (PK, ALK, EK) showed no significant impact on the need for tectonic grafts (P = 0.45) or the rate of endophthalmitis (P = 0.55). CONCLUSIONS: The incidence of keratitis after a corneal graft was 1.7%, with Streptococcus viridans and Staphylococcus aureus the most common microorganisms. The rate of endophthalmitis associated with post-keratoplasty keratitis was 0.053%. There was no correlation between the necessity for a tectonic graft or the incidence of endophthalmitis and the type of microorganisms involved.

Open-source, 3D printable IOL holder for detailed, smartphone-based anterior segment photography.

Smartphones are increasingly relevant resources in medical practice as they are ubiquitous and reasonably cheap. Among the advantages of using smartphones in medical practise, there is the possibility of obtaining reproducible photographic documentation of various conditions. This is particularly true in the ophthalmic field, where anterior segment color photography plays a significant role in the diagnosis and the management of ocular surface diseases. Here we propose an original design for an open-source smartphone accessory for taking and sharing high-definition photographs of the anterior segment. It can be easily reproduced via 3D printing, and it only needs to be integrated with an intraocular lens (IOL), widely available to the majority of ophthalmologists. Compared to other solutions described previously, it allows a precise and reproducible placement of the IOL on the smartphone camera, avoiding manual positioning that could result tricky and time-consuming. The IOL holder is cheap, scalable, portable and it can be quickly assembled and disassembled, without permanently modifying the smartphone camera.

Efficacy and safety of combined UV-light corneal crosslinking and fine-needle diathermy to regress pathological murine corneal (lymph)angiogenesis in vivo.

PURPOSE: To compare safety and efficacy of isolated and combined UV-light corneal crosslinking (CXL) and fine-needle diathermy (FND) to regress pathological corneal vessels in vivo. METHODS: Mice with inflamed and pathologically vascularized corneas received CXL or FND as monotherapy or a combination of both treatments. Corneal pathological blood and lymphatic vessels, immune cells and the morphology of anterior segment structures were evaluated. RESULTS: All three approaches were able to regress blood and lymphatic vessels in mice. A comparative analysis of the three methods revealed that the FND monotherapy and the CXL + FND combination were significantly more effective than the CXL monotherapy, one and 2 weeks after therapy and especially in regressing lymphatic vessels. Furthermore, the combination therapy induced significantly less immune cell recruitment compared to the monotherapies. All three methods were safe to use in regards of corneal integrity. CONCLUSIONS: A combination of FND and CXL led to regression of pathological corneal lymphatic and blood vessels and reduced the infiltration of immune cells into inflamed murine corneas. This approach offers a new effective, safe and clinically usable strategy to treat eyes with mature pathological blood vessels and even more so for lymphatic vessels, for example prior to high-risk corneal transplantation.

Suppression of Neovascularization by Topical and Subconjunctival Bevacizumab After High-Risk Corneal Transplantation.

Purpose: To assess the effectiveness of topical and subconjunctival bevacizumab in suppressing vascularization in graft and host bed after high-risk corneal transplantation. Design: Secondary analysis of prospective, randomized, double-blind, placebo-controlled multicentric clinical trial. Participants: The study includes patients aged > 18 years who underwent high-risk penetrating keratoplasty, which was defined as corneal vascularization in ≥ 1 quadrants of the corneal graft and host bed, excluding the limbus. Methods: Patients were randomized to treatment and control groups. The patients in the treatment group received subconjunctival injection of bevacizumab (2.5 mg/0.1 ml) on the day of the procedure, followed by topical bevacizumab (10 mg/ml) 4 times per day for 4 weeks. The patients in control group received injection of vehicle (0.9% sodium chloride) on the day of procedure, followed by topical vehicle (carboxymethylcellulose sodium 1%) 4 times a day for 4 weeks. Main Outcome Measures: Vessel and invasion area of vessels in the corneal graft and host beds. Results: This study included 56 eyes of 56 patients who underwent high-risk corneal transplantation, with equal numbers in the bevacizumab and vehicle (control) treatment groups. The mean age of patients who received bevacizumab was 61.2 ± 15.9 years, and the mean age of those treated with vehicle was 60.0 ± 16.1 years. The vessel area at baseline was comparable in the bevacizumab (16.72% ± 3.19%) and control groups (15.48% ± 3.12%; P = 0.72). Similarly, the invasion areas were also similar in the treatment (35.60% ± 2.47%) and control (34.23% ± 2.64%; P = 0.9) groups at baseline. The reduction in vessel area was significantly higher in the bevacizumab-treated group (83.7%) over a period of 52 weeks compared with the control group (61.5%; P < 0.0001). In the bevacizumab-treated group, invasion area was reduced by 75.8% as compared with 46.5% in the control group. The vessel area was similar at 52 weeks postprocedure in cases of first (3.54% ± 1.21%) and repeat (3.80% ± 0.40%) corneal transplantation in patients who received bevacizumab treatment. In the vehicle-treated patients, the vessel area was significantly higher in repeat (9.76% ± 0.32%) compared with first (8.06% ± 1.02%; P < 0.0001) penetrating keratoplasty. In the bevacizumab treatment group, invasion areas at week 52 were comparable in first (11.70% ± 3.38%) and repeat (11.64% ± 1.74%) procedures, whereas invasion area was significantly higher in repeat (27.87% ± 2.57%) as compared with first (24.11% ± 2.17%) penetrating keratoplasty in vehicle-treated patients. Conclusions: In patients undergoing vascularized high-risk corneal transplantation, bevacizumab is efficacious in reducing vascularization of corneal graft and host bed, thereby reducing the risk of corneal graft rejection in vascularized host beds. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Risk of Corneal Transplant Rejection Following COVID-19 Vaccination: A Systematic Review and Meta-analysis.

INTRODUCTION: The COVID-19 pandemic has initiated an unparalleled global vaccination campaign, raising concerns about the vaccine's effects on various health conditions, including the risk of corneal transplant rejection. This systematic review aimed to identify the relationship between COVID-19 vaccination and rejection of corneal transplant, filling a significant gap in the existing medical literature. METHODS: A literature search was performed across multiple databases up to February 12, 2024, to identify studies evaluating the risk of corneal transplant rejection post-COVID-19 vaccination. Eligible studies were original research that reported outcomes of corneal graft rejection following vaccination. Nested Knowledge web software facilitated screening and data extraction. The Newcastle-Ottawa Scale was employed for quality assessment. A meta-analysis was conducted to calculate the aggregated relative risk (RR) utilizing R software version 4.3. RESULTS: Six studies were included in the qualitative synthesis, with four meeting the criteria for meta-analysis. These studies varied in geographic location, surgical techniques, and types of vaccines used. The pooled RR for corneal transplant rejection following COVID-19 vaccination was 0.816 (95% CI 0.178-1.453), indicating no significant risk of rejection. No statistical heterogeneity was observed among the studies (I2 = 0%). CONCLUSIONS: This review and meta-analysis found no significant evidence that COVID-19 vaccination increases the risk of corneal graft rejection. However, the current evidence is insufficient to conclusively determine the vaccine's safety for corneal transplant recipients. These findings underscore the need for additional research to confirm these preliminary results and investigate the long-term effects of COVID-19 vaccination on corneal transplants, aiming to provide evidence-based guidance to healthcare providers and patients.

Cyclic guanosine monophosphate-adenosine monophosphate synthetase/stimulator of interferon genes signaling aggravated corneal allograft rejection through neutrophil extracellular traps.

The activation of innate immunity following transplantation has been identified as a crucial factor in allograft inflammation and rejection. However, the role of cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)/stimulator of interferon genes (STING) signaling-mediated innate immunity in the pathogenesis of allograft rejection remains unclear. Utilizing a well-established murine model of corneal transplantation, we demonstrated increased expression of cGAS and STING in rejected-corneal allografts compared with syngeneic (Syn) and normal (Nor) corneas, along with significant activation of the cGAS/STING pathway, as evidenced by the enhanced phosphorylation of TANK-binding kinase 1and interferon regulatory factor 3. Pharmacological and genetic inhibition of cGAS/STING signaling markedly delayed corneal transplantation rejection, resulting in prolonged survival time and reduced inflammatory infiltration. Furthermore, we observed an increase in the formation of neutrophil extracellular traps (NETs) in rejected allografts, and the inhibition of NET formation through targeting peptidylarginine deiminase 4 and DNase I treatment significantly alleviated immune rejection and reduced cGAS/STING signaling activity. Conversely, subconjunctival injection of NETs accelerated corneal transplantation rejection and enhanced the activation of the cGAS/STING pathway. Collectively, these findings demonstrate that NETs contribute to the exacerbation of allograft rejection via cGAS/STING signaling, highlighting the targeting of the NETs/cGAS/STING signaling pathway as a potential strategy for prolonging allograft survival.

Myeloid-derived suppressor cells promote allograft survival by suppressing regulatory T cell dysfunction in high-risk corneal transplantation.

Highly inflamed and neovascularized corneal graft beds are known as high-risk (HR) environments for transplant survival. One of the primary factors leading to this rejection is reduction in the suppressive function of regulatory T cells (Treg). Our results show that myeloid-derived suppressor cells (MDSC) counteract interleukin-6-mediated Treg dysfunction by expressing interleukin-10. Additionally, MDSC maintain forkhead box P3 stability and their ability to suppress IFN-γ+ Th1 cells. Administering MDSC to HR corneal transplant recipients demonstrates prolonged graft survival via promotion of Treg while concurrently suppressing IFN-γ+ Th1 cells. Moreover, MDSC-mediated donor-specific immune tolerance leads to long-term corneal graft survival as evidenced by the higher survival rate or delayed survival of a second-party C57BL/7 (B6) graft compared to those of third-party C3H grafts observed in contralateral low-risk or HR corneal transplantation of BALB/c recipient mice, respectively. Our study provides compelling preliminary evidence demonstrating the effectiveness of MDSC in preventing Treg dysfunction, significantly improving graft survival in HR corneal transplantation, and showing promising potential for immune tolerance induction.

UV light-mediated corneal crosslinking as (lymph)angioregressive pretreatment to promote graft survival after subsequent high-risk corneal transplantation (CrossCornealVision): protocol for a multicenter, randomized controlled trial.

BACKGROUND: Good vision highly depends on the transparency of the cornea, which is the "windscreen" of the eye. In fact, corneal blindness due to transparency loss is the second most common cause of blindness worldwide, and corneal transplantation is the main cure. Importantly, the cornea is normally avascular but can secondarily be invaded by pathological (blood and lymphatic) vessels due to severe inflammation, and the survival prognosis of a corneal graft mainly depends on the preoperative vascular condition of the recipient's cornea. Whereas transplants placed into avascular recipient beds enjoy long-term survival rates of > 90%, survival rates significantly decrease in pathologically pre-vascularized, so-called high-risk recipients, which account for around 10% of all performed transplants in Germany and > 75% in lower and middle-income countries worldwide. METHODS: This parallel-grouped, open-randomized, multicenter, prospective controlled exploratory investigator-initiated trial (IIT) intends to improve graft survival by preconditioning pathologically vascularized recipient corneas by (lymph)angioregressive treatment before high-risk corneal transplantation. For this purpose, corneal crosslinking (CXL) will be used, which has been shown to potently regress corneal blood and lymphatic vessels. Prior to transplantation, patients will be randomized into 2 groups: (1) CXL (intervention) or (2) no pretreatment (control). CXL will be repeated once if insufficient reduction of corneal neovascularization should be observed. All patients (both groups) will then undergo corneal transplantation. In the intervention group, remaining blood vessels will be additionally regressed using fine needle diathermy (on the day of transplantation). Afterwards, the incidence of graft rejection episodes will be evaluated for 24 months (primary endpoint). Overall graft survival, as well as regression of corneal vessels and/or recurrence, among other factors, will be analyzed (secondary endpoints). DISCUSSION: Based on preclinical and early pilot clinical evidence, we want to test the novel concept of temporary (lymph)angioregressive pretreatment of high-risk eyes by CXL to promote subsequent corneal graft survival. So far, there is no evidence-based approach to reliably improve graft survival in the high-risk corneal transplantation setting available in clinical routine. If successful, this approach will be the first to promote graft survival in high-risk transplants. It will significantly improve vision and quality of life in patients suffering from corneal blindness. TRIAL REGISTRATION: ClinicalTrials.gov NCT05870566. Registered on 22 May 2023.

[Outcomes of hemi-Descemet membrane endothelial keratoplasty and phacoemulsification for the treatment of primary Fuchs' endothelial corneal dystrophy combined with cataract]. / Rezul'taty transplantatsii destsemetovoi membrany s endoteliem i fakoemul'sifikatsii pri pervichnoi endotelial'noi distrofii rogovitsy Fuksa, sochetannoi s kataraktoi.

PURPOSE: This study evaluates the long-term results of surgical treatment of patients with Fuchs' endothelial corneal dystrophy and cataract. MATERIAL AND METHODS: The study included 24 patients (24 eyes) with primary Fuchs' endothelial corneal dystrophy and cataract, who underwent cataract phacoemulsification with IOL implantation and of Descemet's membrane endothelial keratoplasty with a semicircular graft (hemi-DMEK). The effect of treatment was assessed by best corrected visual acuity (BCVA), central corneal thickness (CCT) and endothelial cell density (ECD). RESULTS: In total, surgical treatment involved 14 donor corneas that were divided in half during the preparation and isolation of the Descemet's membrane (DM). By month 12 after the surgery an increase in visual functions and graft transparency were observed in 23 patients (23 eyes) out of 24. Repeated keratoplasty was required in one case due to fibrosis of the posterior layers of recipient's corneal stroma. At 12 months postoperatively, the study group showed an increase in BCVA from 0.16±0.1 to 0.75±20, a decrease in CCT from 650.9±4.5 µm to 519.6±43.9, and a decreased in ECD from 2850.5±84.7 cells/mm2 up to 1285.5±277.2 cells/mm2. Thus, the loss of endothelial cells at one year after surgery amounted to 54.9%. CONCLUSIONS: The developed method for transplantation of a semicircular DM fragment provides a tissue-saving approach to endothelial keratoplasty, and considering the high percentage of transparent engraftment of grafts and complete visual rehabilitation, it can be recommended in the treatment of patients with cataract and Fuchs' endothelial corneal dystrophy.

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.

Towards Precision Ophthalmology: The Role of 3D Printing and Bioprinting in Oculoplastic Surgery, Retinal, Corneal, and Glaucoma Treatment.

In the forefront of ophthalmic innovation, biomimetic 3D printing and bioprinting technologies are redefining patient-specific therapeutic strategies. This critical review systematically evaluates their application spectrum, spanning oculoplastic reconstruction, retinal tissue engineering, corneal transplantation, and targeted glaucoma treatments. It highlights the intricacies of these technologies, including the fundamental principles, advanced materials, and bioinks that facilitate the replication of ocular tissue architecture. The synthesis of primary studies from 2014 to 2023 provides a rigorous analysis of their evolution and current clinical implications. This review is unique in its holistic approach, juxtaposing the scientific underpinnings with clinical realities, thereby delineating the advantages over conventional modalities, and identifying translational barriers. It elucidates persistent knowledge deficits and outlines future research directions. It ultimately accentuates the imperative for multidisciplinary collaboration to enhance the clinical integration of these biotechnologies, culminating in a paradigm shift towards individualized ophthalmic care.

Rho-kinase inhibitor alleviates CD4+T cell mediated corneal graft rejection by modulating its STAT3 and STAT5 activation.

Penetrating keratoplasty remains the most common treatment to restore vision for corneal diseases. Immune rejection after corneal transplantation is one of the major causes of graft failure. In recent years, Rho-associated protein kinase (ROCK) inhibitors have been found to be associated with the activation of the STATs pathway and are widely studied in autoimmune diseases. Therefore, it may be possible that the ROCK inhibitors also participate in the local and systemic immune regulation in corneal transplantation through activation of the STATs pathway and affect the CD4+ T cell differentiation. This study aimed to explore the role of ROCK-STATs pathway in the occurrence of immune rejection in corneal transplantation by applying Y27632, a ROCK inhibitor, to the recipient mice and peripheral CD4+ T cells. We found that Y27632 significantly up-regulated the phosphorylation level of STAT5 in both spleen and lymph nodes, down-regulated the phosphorylation level of STAT3 in the CD4+ T cells in the spleen. It also increased the proportion of CD4+CD25+Foxp3+Helios+ Tregs while decreased CD4+IL17A+ -Th17 cells. Moreover, Y27632 also reduced the proportion of dendritic cells in both spleen and lymph nodes, as well as the expression level of CD86 on their surfaces in the spleen, while the proportion of macrophages was not affected. The expression levels of ROCK1, ROCK2, CD11c and IL-17A mRNA were also found to be low in the graft tissue while the expression of Helios was upregulated. Rho-kinase inhibitor can modulate the balance of Tregs/Th17 by regulating the phosphorylation levels of both STAT3 and STAT5, thereby inhibiting the occurrence of immune rejection in allogeneic corneal transplantation.