Keratoplasty Research Articles

Evaluation of the clinical efficacy of modified LSC transplantation plus BCL implantation in the treatment of pterygium

ObjectiveTo explore the clinical efficacy of modified limbal stem cell transplantation(Modified LSC transplantation) and bandage contact lens(BCL) implantation in pterygium surgery.MethodsA total of 479 patients with primary pterygium who were admitted to our hospital from March 2019 to March 2023 were randomly divided into three groups: the normal group (Group A: 89 patients), the control group (Group B: 195 patients), and the modified group (Group C: 195 patients). Each group received different intervention measures. Group A did not undergo surgical treatment and were required to follow up as outpatients. Group B received LSC transplantation combined with interrupted suturing plus BCL, whereas Group C received modified LSC transplantation combined with BCL. The degree of corneal irritation symptoms, wound healing and graft status under slit lamp, incidence and recurrence rate of complications, tear film rupture time, tear secretion test, intraocular pressure, ocular surface inflammation response(IL-1β, PGE2, TNF-α, VEGF), and visual quality were compared and analyzed at various time points after surgery.ResultsCompared with those in the Group B, patients in the Group C experienced faster normalization of corneal epithelium recovery, fewer corneal irritation symptoms, and better wound healing. The break-up time (BUT) of the tear film at 1 week to 1 year postoperatively was significantly greater in the Group C than Group B, with values approaching those of Group A by 3 months (P < 0.05). The Schirmer test results revealed a similar trend to that of the BUT. Further analysis of intraocular pressure (IOP) at different time points revealed no significant differences among the three groups at postoperative Day 1. However, due to the use of corticosteroid eye drops postoperatively, IOP was greater in both the Group B(17.24 ± 2.12 mmHg) and Group C (17.02 ± 2.37 mmHg) than Group A (13.92 ± 1.57 mmHg) at 1 week. By 1 month, Group C had a lower IOP (15.77 ± 1.63 mmHg) than Group B(17.78 ± 2.41 mmHg). There were no significant differences in IOP among the three groups from 3 months to 1 year (P > 0.05). The ELISA results indicated that the expression levels of the ocular surface inflammatory factors IL-1β, TNF-α, PEG2, and VEGF in the Group C were lower than those in Group B from 1 week to 1 year post surgery. Under both natural light and low-light conditions (spatial frequency/6 cd), Group C had better best-corrected visual acuity and contrast sensitivity than Group B at 1 week to 1 year postoperatively. Additionally, Group C had lower corneal higher-order aberrations (including astigmatism, spherical aberrations, and total higher-order aberrations) and superior vision-related quality of life scores at 1 year postoperatively than Group B, with statistically significant differences (P < 0.05).ConclusionModified LSC transplantation combined with BCL implantation provided superior treatment outcomes for patients with pterygium, which was worthy of further clinical promotion.

Keratoprosthesis of Brazil (KoBra): Preliminary Results of the First 2 Human Cases

Purpose: We evaluated the clinical performance of a novel keratoprosthesis (KPro) named KoBra (Keratoprosthesis of Brazil) in patients with corneal blindness. Methods: Two-piece KPro was three-dimensionally (3D) printed using titanium alloy powder (Ti-6Al-4V) and polymethyl methacrylate (PMMA). The KPros were implanted unilaterally in 2 patients who had corneal disease that was not amenable to standard corneal transplantation. An autologous full-thickness corneal graft was used as the KPro carrier. Patients were examined for at least 16 months to evaluate retention and postoperative complications. Biomicroscopy and anterior segment optical coherence tomography (AS-OCT) were performed throughout the experiment to evaluate the relationship between the KPro and the carrier graft. Results: No intraoperative complications occurred during the surgeries, and the immediate postoperative period was uneventful. The implanted KoBra integrated well into all operated eyes, and clear optics without prothesis extrusion were maintained. The mean duration of the postoperative follow-up was 17 months (range 16–18 months). AS-OCT demonstrated the correct relationship of the device and carrier at the final follow-up in all cases. Conclusions: The first short-term clinical analysis demonstrated good outcomes associated with this new technology in 2 patients who were not amenable to standard corneal transplantation. Longer follow-up and additional implantations are necessary to better assess the safety and efficacy of this device.

Clinical and surgical outcomes of tectonic corneal patch grafts : insights from a tertiary referral hospital

PurposeThis study aimed to report the clinical characteristics, surgical indications, outcomes and long-term complications of full-thickness or lamellar corneal patch grafts for various indications.Material-methodThis retrospective study included 48 eyes of 47 patients who underwent full-thickness or lamellar corneal patch keratoplasty for treatment of corneal perforation, melting and descemetocele. Patient demographics, preoperative features, best-corrected visual acuity before and after surgery, mean follow-up time, corneal graft type, long-term complications, need for additional surgery, and anatomical success were analyzed.ResultsOf the 48 eyes, 21 had corneal perforation, 21 had severe corneal melting, and six had descemetocele. Sjögren’s syndrome (eight eyes, 16.7%), trauma (eight eyes, 16.7%), and limbal stem cell deficiency (eight eyes, 16.7%) were the most common indications for corneal patch grafting. The most common complications after surgery were graft melting (11 eyes, 22.9%) and glaucoma (5 eyes, 10.4%). One eye developed phthisis bulbi. Penetrating keratoplasty was performed in 8 of the 11 eyes with recurrent graft melting. All descemetocele cases were central and corneal melts were more frequently located paracentrally (p = 0.0001). Anatomical success was achieved in 39 eyes (81.2%).ConclusionCorneal patch grafting is a safe and effective method for maintaining ocular integrity in corneal melting and perforation that can not be closed using conventional methods. With a success rate of over 80%, corneal patch grafts can delay a larger full-thickness graft, especially in eyes with acute inflammation, until systemic therapy is effective.

Cost-Effectiveness of Corneal Collagen Crosslinking for Progressive Keratoconus: A Brazilian Unified Health System Perspective

Keratoconus is a burden to health systems and patients worldwide. Corneal collagen crosslinking (CXL) treatment has been shown abroad to be cost-effective for treating progressive keratoconus. However, no cost-effectiveness studies have been performed in Brazil. The aim of this study was to assess the cost-effectiveness of corneal collagen crosslinking (CXL) compared with the conventional treatment for progressive keratoconus from the Brazilian Unified Health System (SUS) payer’s perspective. A lifetime microsimulation model was utilized to compare the lifetime costs and quality-adjusted life years for patients undergoing corneal collagen CXL or conventional treatment. Two groups of 5000 18-year-old patients were simulated, with one group receiving corneal CXL at the outset and the control group remaining untreated. The TreeAge Pro Healthcare 2024 software was used for modeling and analysis. Corneal collagen CXL demonstrated superior cost-effectiveness compared to the conventional treatment, with an incremental cost-effectiveness ratio of 58.26 USD/quality-adjusted life years (QALY) gained (95% CI: 58.17–58.36) and a positive incremental net monetary benefit of USD 11,613.82 (95% CI: 11,605.66–11,621.99). CXL significantly reduced the number of required corneal transplants, with a mean of 968.8 (95% CI: 959–978.58) fewer transplants per 10,000 eyes treated. The variable with the most significant impact on the incremental net monetary benefit was the duration of the CXL effect. This study concluded that corneal CXL is a highly cost-effective intervention for progressive keratoconus within the Brazilian SUS. These findings advocate for broader accessibility to this vision-saving treatment within the SUS.

Machine learning methods to identify risk factors for corneal graft rejection in keratoconus

Machine learning can be used to identify risk factors associated with graft rejection after corneal transplantation for keratoconus. The study included all keratoconus eyes that underwent primary corneal transplantation from 1994 to 2021. Data relating to the recipient, donor, surgery, and postoperative course that might be associated with the occurrence of a graft rejection reaction were compiled. This study used five supervised learning algorithms including artificial neural network, support vector machine, gradient boosting, extra trees classifier, and random survival forests to select the most predictive factors for graft rejection. A total of 1214 consecutive eyes of 985 keratoconus patients were included in the study, and the technique of keratoplasty included penetrating keratoplasty in 574 eyes (47.3%) and deep anterior lamellar keratoplasty in 640 eyes (52.7%). The overall prevalence of first graft rejection was 28.1%. All five models had similar ability in identifying predictive factors for corneal graft rejection. Technique of keratoplasty was associated with an increased risk of graft rejection in all models. Other identified risk factors included patient age, keratoplasty in the fellow eye, donor age, graft endothelial cell density, duration of corticosteroid application, time from keratoplasty to complete suture removal, and suture-associated complications. It is advisable that in the absence of any contraindication, post-transplant keratoconus eyes receive a low dose topical corticosteroid until all sutures are removed.

Comparison of Intraocular Pressure Measurements Using Three Different Methods (Goldmann Applanation Tonometry (GAT), Corvis ST, and iCare) Following Penetrating Keratoplasty

Background/Objectives: Intraocular pressure (IOP) readings using three different methods (Goldmann applanation tonometry (GAT), Corvis ST, and iCare) were compared in patients who underwent penetrating keratoplasty (PK). Methods: An observational cross-sectional study with prospective recruitment of patients was conducted. IOP measurements were acquired using GAT, iCare, and Corvis (including both uncorrected IOP (CVS-IOP) and biomechanical IOP (bIOP)), and the agreement among methods was analyzed using Bland–Altman plots. Secondary outcomes included the influence of CCT, the number of sutures, the size of the corneal donor button, and the use of antiglaucoma topical medications on the IOP readings using the three methods. Results: Twenty-five eyes from 25 patients were included. The Bland–Altman analysis showed the narrowest limits of agreement (LoA) between GAT and bIOP (7.5 mmHg). The difference between iCare and GAT IOP showed a bias of 1.26 ± 3.8 mmHg, with increased variability in cases with more remaining sutures (p = 0.0079). A higher CCT was moderately associated with lower bIOP readings (p = 0.0067), but no significant impact of CCT on the difference in the IOP measurements between GAT and other tonometers was found. Additionally, there were no significant differences in tonometer readings based on the use of antiglaucoma medications or the corneal donor button size. Conclusions: Good agreement was found between iCare, CVS-IOP, bIOP, and GAT-IOP readings with the comparison between GAT-IOP and bIOP resulting in the narrowest 95% LoA. The difference between the GAT-IOP and iCare readings tended to be influenced by the number of sutures at the graft–host interface. Higher CCT values were associated with lower bIOP readings; however, the differences in tonometer readings compared to GAT-IOP were not found to be influenced by CCT.

Natural Extracellular Matrix Scaffold-Based Hydrogel Corneal Patch with Temperature and Light-Responsiveness for Penetrating Keratoplasty and Sutureless Stromal Defect Repair.

Corneal transplantation remains the gold standard for treating corneal blindness; however, it is hampered globally by donor shortages and the complexity of suture-dependent procedures. Tissue-engineered corneas have demonstrated potential as corneal equivalents. Nevertheless, the development of adhesive corneal patches and full-thickness corneal substitutes remains challenging. In this study, a multifunctional hydrogel corneal patch (MHCP) is constructed by integrating a dual-crosslinked hybrid hydrogel with temperature and light responsiveness with a natural extracellular matrix scaffold. When applied to the ocular surface, MHCP spontaneously releases adhesives at body temperature and forms a stable adhesion with the recipient cornea through photocuring. In addition to its inherent mechanical, optical, and ultrastructural characteristics, which are similar to those of the natural stroma, MHCP demonstrates excellent suture resistance, anti-swelling, and anti-degradation properties after curing. MHCP promotes the proliferation and migration of corneal epithelial cells in vitro and maintains the phenotype of corneal stromal cells. In vivo, MHCP maintains graft hydration and restores corneal structural integrity and transparency during penetrating keratoplasty of various sizes and sutureless lamellar keratoplasty. Collectively, given the advantages of native stroma-like characteristics, operation-facilitating multiple functions, and convenient preparation, MHCP is a promising corneal substitute for clinical applications.

Human embryonic stem cell-derived immunity-and-matrix-regulatory cells on collagen scaffold effectively treat rat corneal alkali burn

Corneal alkali burns (CAB) are a severe form of ocular injury that often leads to significant vision loss, with limited effective treatment options available beyond corneal transplantation. Immunity and matrix-regulatory cells (IMRCs) have emerged as a promising alternative due to their ability to modulate immune responses and support tissue repair. This study investigates the efficacy of IMRCs on collagen scaffolds (IMRCs-col) for treating CAB in a rat model. We developed a novel treatment combining IMRCs with a collagen scaffold to align with the ocular surface structure. In vitro analyses showed that IMRCs-col significantly upregulated the expression of immune regulatory molecules, including IL-1RA and SCF. Additionally, IMRCs-col effectively inhibited the production of pro-inflammatory cytokines (IL-8 and Gro-a/CXCL1) while promoting pro-regenerative cytokines (bFGF, HGF, and PDGF). In an animal model of CAB, IMRCs-col transplantation demonstrated substantial efficacy in restoring corneal opacity and reducing neovascularization. Histological examination revealed reduced inflammation and improved corneal tissue regeneration compared to untreated CAB. Enhanced activation of pathways associated with anti-inflammatory responses and tissue repair was observed at days 3, 7, and 21 post-treatment.

Intrastromal graft of anterior lens capsule. A substitute for Bowman layer graft transplantation for keratoconus.

The shortage of donor corneas limits Bowman layer transplantation for keratoconus. In this study, we evaluate the clinical outcome of porcine anterior lens capsule (xenograft) transplantation in the corneal stroma of a rabbit model as substitute for Bowman layer graft that is used in stromal transplantation for advanced keratoconus. Transplantation of porcine anterior lens capsule in the corneal stroma was performed in four New Zealand white rabbits through the creation of a stromal pocket. Corneal transparency, central corneal thickness, and topographic characteristics of corneas were evaluated at different time points: pre- (0) and post- (7, 14, 21, and 28) operative days. Additionally, at the end of the study histopathological findings were evaluated. In comparison to pre-operative day, transplantation of an anterior lens capsule preserved corneal transparency, central corneal thickness, and topographic characteristics remained constant throughout the study period. Histopathological analysis revealed the presence of the anterior lens capsule as a fully integrated lamellar graft without adverse effects in host stroma. The anterior lens capsule may be useful as a graft for intrastromal corneal trasplantation. Similarly to Bowman layer, anterior lens capsule has mechanical characteristics that facilitate corneal transplantation. In post-transplanted corneas the preservation of transparency, as well as the effect on corneal thickness, and topographic characteristics support the possibility of using anterior lens capsule as a substitute for Bowman layer graft.

Keratoplasty to restore vision in trachomatous corneal opacity: A literature review

Background Trachoma is the leading infectious cause of blindness. Patients with trachomatous corneal opacity (TCO) are traditionally considered high-risk cases for graft failure. However, anecdotal evidence suggests that corneal transplantation may restore vision in such individuals. We wanted to review the available evidence for keratoplasty outcomes in TCO. Methods A literature search of PubMed, MEDLINE, and Web of Science was performed using the search terms “trachoma* AND (keratoplasty OR cornea* transplant*)”. The search was restricted to studies published between 1 January 1992 and 12 October 2022. All types of prospective and retrospective study designs reporting outcomes of keratoplasty in trachoma were included. The primary outcome assessed was rate of graft survival in patients with TCO who received keratoplasty. Secondary outcomes were postoperative best corrected visual acuity (BCVA) and graft rejection rates. Results Seven studies met our inclusion criteria. None were prospective trials; 215/302 grafts (71%) were clear at final follow-up. There was significant variability between studies in the reporting of patient characteristics, follow-up, complications, and outcomes. In data on penetrating keratoplasty (PKP), graft survival at final follow-up was observed in 161/195 eyes (83%). Studies assessing lamellar keratoplasty (LKP) reported graft survival in 18/20 eyes (90%). Rejection episodes were reported in 31/167 (19%) eyes managed with PKP and 0 of 20 eyes managed with LKP. Of 163 eyes, preoperative BCVA was ≤counting fingers in 76% and ≤6/60 in 91%. A postoperative BCVA of &gt;6/60 was achieved in 63% of eyes. Conclusions There is a paucity of evidence supporting keratoplasty in TCO. However, it may hold visual rehabilitation promise for people whose needs have to date been largely ignored. More structured reporting of outcomes from centres which perform keratoplasty in TCO and a well-designed prospective study would be valuable additions to the literature.

Comparison of clinical outcomes, complications and patient satisfaction following deep anterior lamellar keratoplasty and penetrating keratoplasty

BackgroundKeratoplasty is a surgical procedure in which a damaged or diseased cornea is replaced with healthy donor tissue, thereby restoring vision. Recent advancements have led to the replacement of penetrating keratoplasty (PKP) with the more selective deep anterior lamellar keratoplasty (DALK) procedure, especially for treating keratoconus. Although DALK typically has a shorter recovery time, less pain and a lower risk of rejection, PKP is still being performed for more severe corneal diseases. A comparative study of clinical profiles, treatment outcomes and patient-reported satisfaction will provide valuable insights into the cost-effectiveness, impact on quality of life and ability of each procedure to treat different pathologies of the cornea. Here, we aimed to compare the clinical and subjective outcomes of DALK with those of the PKP at a single center in the Kingdom of Saudi Arabia.MethodsThis retrospective cohort study included eyes that underwent either PKP or DALK from January 2017 to January 2021. The demographic features, indications, best corrected visual acuity (BCVA) and complications of the patients were recorded for both groups, analyzed and compared. A subgroup of eyes with keratoconus was analyzed separately and compared to the larger group. A 6-item survey was conducted via telephone to assess patient satisfaction and expectation, and the results were compared between the two procedures. The chi-square test or Fisher’s exact test for categorical variables or the t test or Kruskal‒Wallis test for continuous variables were used as appropriate for all comparisons, and the level of significance was set at α = 0.05.ResultsA total of 97 patients were included. PKP and DALK were performed on 63 and 39 eyes, respectively. Patients who underwent DALK were younger (mean ± standard deviation 31 ± 10.82 years versus 43 ± 26.89 years for patients who underwent PKP). The most frequent indication for PKP was keratoconus (35.5%); however, in 97.4% of the eyes undergoing DALK, the indication was keratoconus. In both groups, visual acuity and refractive error improved, but the postoperative corrected distance visual acuity in the DALK group (0.3 log MAR) was noticeably greater than that in the PKP group (0.6 log MAR). Compared with PKP, DALK may carry a lower risk of early graft edema and rejection. Overall, the reported postoperative patient satisfaction was similar for both procedures.ConclusionThe findings highlight the effectiveness of PKP and DALK in improving visual acuity and emphasize the importance of considering patient-reported outcomes in evaluating success. DALK has been demonstrated to be beneficial for protecting the corneal endothelium and lowering the risk of complications and graft rejection.

Harnessing Tumor Cell-Derived Exosomes for Immune Rejection Management in Corneal Transplantation.

Transplantation remains the definitive treatment for end-stage organ failures, but its efficacy is frequently compromised by immune rejection. This study introduces a novel strategy by utilizing tumor-derived exosomes from B16-F10 melanoma cells (B16-Exo), diverging from the conventional use of immune cell-derived exosomes, to alleviate post-transplantation immune rejection. Utilizing murine corneal transplantation as a model, it is demonstrated that B16-Exo significantly reduces immune rejection, evidenced by decreased corneal opacity, neovascularization, and immune dysregulation, while enhancing postoperative survival. Proteomic analyses reveal differential expression of pivotal proteins in B16-Exo, notably the JAK2 protein within the JAK-STAT signaling pathway, which has been mechanistically demonstrated to amplify the activity of myeloid-derived suppressor cells (MDSCs) and inhibit T cell proliferation. These findings demonstrate the significant immunomodulatory effect of B16-Exo in transplant immunology, supporting the continued exploration of tumor-derived exosomes as a platform to uncover novel immunosuppressive mechanisms in transplantation.

A novel sandwich technique of minimally invasive surgery for corneal perforation

This study aimed to describe a novel sandwich technique of minimally invasive surgical implantation by using corneal stromal lenticules for corneal perforation. This prospective observational study included nine patients aged 23–79 years (mean, 54 ± 9) from Tianjin Eye Hospital. Corneal stromal lenticules with a central thickness of 120 μm were obtained from small incision lenticule extraction(SMILE). With the corneal perforation as the central point, an iris-repositor was used to manually create a mid-stromal pocket; the stromal lenticular button was gently inserted into the intrastromal pocket and flattened. The graft was sandwiched between the anterior and posterior corneal stromal pockets; the incision was closed using two sutures. The primary health outcome measured in this study was the logMAR best spectacle-visual acuity at 6 months postoperatively. Corneal perforation closure and anterior chamber formation occurred immediately after surgery. No epithelial implantation, infection, or allogeneic rejection was observed during the follow-up. No patients required a penetrating keratoplasty. Anterior segment optical coherence tomography revealed a mean thickness of the grafted tissue of 122 ± 21 μm, with a clear interface in all cases. Comparing the baseline and postoperative 6-month values, the mean logMAR best spectacle-corrected visual acuity was improved from 0.18 ± 0.12 to 0.52 ± 0.31 (P < 0.001). There was significant reduction in the mean manifest spherical equivalent, refractive cylinder, and mean keratometry readings. The novel minimally invasive surgical method for corneal implantation. It was an effective alternative treatment that could restore corneal integrity and improve vision in patients with corneal perforations. This method appears safe, easy, cost- and time-effective, and reliable.

Dupilumab-Associated Bilateral Conjunctival Papillomas and Corneal Perforation.

We report a unique case of significant human papillomavirus-associated conjunctival papillomas and severe corneal ulceration leading to corneal perforation in a patient treated with dupilumab for atopic dermatitis. This study is a case report and literature review of severe corneal side effects related to dupilumab. A 27-year-old man with severe atopic dermatitis and no ocular history was administered dupilumab 300 mg via subcutaneous injections every 2 weeks with an excellent response. Following the onset of treatment, the patient developed conjunctivitis, conjunctival papillomas, and dry eyes, which were initially treated with lubricating eye drops. Fourteen months after commencing dupilumab, he had a rapid onset of painful visual loss in the OD accompanied by severe bilateral conjunctival injection and was found to have a central corneal ulcer and diffuse papillomas on the palpebral and bulbar conjunctiva. Despite management with intravenous methylprednisolone and topical dexamethasone, the patient's corneal ulcer progressed to a corneal melt, resulting in perforation 2 months after diagnosis, which necessitated a corneal graft. We present the third reported case of dupilumab-associated corneal perforation and the first case to our knowledge of dupilumab-associated conjunctival papillomas. As dupilumab usage increases, awareness of these potential complications among prescribers is essential.

Five years of emergency keratoplasty at a tertiary eye hospital.

The aim of this study is to present the results of patients who underwent emergency keratoplasty for tectonic or therapeutic reasons. Medical records of 33 patients who underwent tectonic or therapeutic keratoplasty at Ege University Department of Ophthalmology between January 2019 and January 2024 were retrospectively evaluated. Demographic characteristics, ocular and systemic findings, indications of keratoplasty, size of grafts, need for re-keratoplasty, preoperative treatment modalities, need for additional surgical interventions, and prognosis of the patients were investigated. During this period, 450 penetrating keratoplasty (PK) surgeries were performed and 34 (7.55%) were emergency PK (34 eyes of 33 patients). The mean age of the patients was 65.30 ± 15.40 (40-91). Female to male ratio was 18/15. 17 (50.00%) emergency PKs were performed for tectonic and 17 (50.00%) were performed for therapeutic purposes. Mean follow up time was 24.85 ± 26.62 (2-120) months. A total of 20 (58.82%) eyes required additional surgery, 9 (26.47%) of which required re-keratoplasty with different indications during follow-up. Graft rejection or failure developed in 17 (50.00%) of the eyes in an average of 12.05 (1-45) months. Evisceration was needed in 2 (5.88%) eyes. Despite limited access to donor cornea and high complication rate, emergency keratoplasty is one of the most important options that retain ocular integrity in the treatment of corneal infections and non-traumatic corneal perforations unresponsive to conventional treatment.

Clinical Outcomes of Infectious Keratitis Associated with Contact Lens Wear Following Penetrating Keratoplasty: A Case Series.

To report on the clinical characteristics, and outcomes of patients who developed infectious keratitis associated with contact lens (CL) wear following penetrating keratoplasty (PK). A retrospective chart review was performed to identify all patients who underwent PK between November 2012 and January 2023 at a single tertiary referral practice, and subsequently developed CL related infectious keratitis. 74 patients using CL following PK were identified. Charts were reviewed to obtain data about demographics, ocular history, CL usage, microbial culture reports, visual acuity, treatment, and clinical outcomes. CL-associated infectious keratitis occurred in 9 patients, more frequently in males (66%), and patients had a mean age of 54.5 ± 11.8years old. The identified causative organisms included: Stenotrophomonas maltophilia (N = 3), Candida parapsilosis (N = 2), Moraxella nonliquefaciens (N = 1), Pseudomonas aeruginosa (N = 1), Staphylococcus epidermidis (N = 1), Streptococcus mitis (N = 1), Candida albicans (N = 1), and Acanthamoeba (N = 1). Contact lenses were used following PK for an average of 9.1 ± 10.8months before development of keratitis. Patients were followed for 31.8 ± 30.2months after infection. The mean best corrected visual acuity without CL prior to infection was 20/150 and decreased to 20/260 post-infection. Complications following the contact-lens-associated infectious keratitis included: central corneal haze (N = 8), chronic corneal epithelial defects (N = 3), perforation (N = 3), endophthalmitis (N = 1), and enucleation (N = 1). Three grafts required repeat PK. CL-associated infectious keratitis following PK have high rates of complication. Patients should be monitored closely for signs of infection.

Deep learning based highly accurate transplanted bioengineered corneal equivalent thickness measurement using optical coherence tomography

Corneal transplantation is the primary treatment for irreversible corneal diseases, but due to limited donor availability, bioengineered corneal equivalents are being developed as a solution, with biocompatibility, structural integrity, and physical function considered key factors. Since conventional evaluation methods may not fully capture the complex properties of the cornea, there is a need for advanced imaging and assessment techniques. In this study, we proposed a deep learning-based automatic segmentation method for transplanted bioengineered corneal equivalents using optical coherence tomography to achieve a highly accurate evaluation of graft integrity and biocompatibility. Our method provides quantitative individual thickness values, detailed maps, and volume measurements of the bioengineered corneal equivalents, and has been validated through 14 days of monitoring. Based on the results, it is expected to have high clinical utility as a quantitative assessment method for human keratoplasties, including automatic opacity area segmentation and implanted graft part extraction, beyond animal studies.

Sociodemographic Predictors of Keratoconus (Severity, Treatment, and Progression) in a Tertiary Center in New York City.

To identify sociodemographic factors as predictors of keratoconus severity, progression, disease outcomes, and appropriate management in a tertiary care ophthalmology institute in the New York City metropolitan area. This is a retrospective chart review. Patients with keratoconus presenting at a tertiary eye institute in an urban setting seen between 2015 and 2022 were included. Sociodemographic data including age, sex, race, ethnicity, income derived from zip code, insurance coverage, and preferred language were recorded. These sociodemographic factors were analyzed as possible predictors of keratoconus severity at presentation (Amsler-Krumeich grades III and IV): patients presenting with acute hydrops, patients receiving corneal cross-linking or corneal transplant, patients showing 1 or more diopters of increase of Kmax during their follow-up, and patients having longer time between the provider's recommendation of corneal cross-linking and the time of the procedure. The retrospective review included 634 patients with a clinical diagnosis of keratoconus. Factors associated with severe keratoconus at presentation in the multivariate analysis were non-White (P < 0.001), lowest income (Q1) (P = 0.018), Q2 income (P = 0.012), and having Medicaid/Medicare coverage (P = 0.021). Medicaid/Medicare coverage was the only factor associated with acute hydrops (P < 0.001), and younger age was the only factor associated with disease progression (P < 0.001). Younger patients and patients with commercial insurance coverage were more likely to receive corneal collagen cross-linking (P < 0.001 and P < 0.001, respectively), whereas patients with Medicaid/Medicare coverage, lowest income, and non-White race were more likely to receive corneal transplantation (P = 0.012, P = 0.062, and P = 0.028, respectively). Medicaid/Medicare was the only factor associated with delay in receiving corneal collagen cross-linking (P = 0.013). Our study demonstrates that there are sociodemographic predictors of keratoconus disease severity, progression, and the type and the time of treatment the patients received. This confirms eye health disparities among patients with keratoconus.

A Novel Artificial Endothelial Replacement Membrane for the Treatment of Chronic Corneal Edema.

The purpose of this study was to report the safety and efficacy results of an artificial lamellar implant for the treatment of chronic corneal edema. The EndoArt (EyeYon Medical, Ness Ziona, Israel), an artificial endothelial replacement membrane designed to treat corneal edema, was implanted in 24 eyes of 24 patients with low-to-normal visual potential. We present the safety and efficacy results from a prospective, open-label, single-arm, multicenter study conducted over a 12-month period. Twenty-four patients were enrolled, with no device-related serious adverse events reported. Seventeen patients completed 12-month follow-up, showing a reduction in average central corneal thickness from 759 ± 116 μm to 613 ± 135 μm. Best-corrected distance visual acuity improved from 1.88 ± 0.79 logarithmic minimum angle of resolution (logMAR) to 1.34 ± 0.57 logMAR. Sixty percent gained at least 3 early treatment diabetic retinopathy study (ETDRS) lines. The EndoArt was removed in 5 cases due to incomplete attachment and replaced by corneal transplants; 1 patient was lost to follow-up, and 1 had a procedure failure. No device-related long-term complications, infections, or inflammations were reported. The implants remained transparent throughout the study. The first-in-human results of EndoArt implantation demonstrated the device's potential to treat patients suffering from corneal edema with a favorable safety profile and effective edema reduction in most subjects, with no device-related serious adverse event. The EndoArt may offer a viable solution in regions facing a shortage of donor corneas, as well as for patients who have poor prognosis with human tissue.

The Triple Procedure in Patients with Congenital Aniridia.

Background: Aniridia is a rare panocular, bilateral, and congenital disease characterized by complete or partial iris hypoplasia and foveal hypoplasia, leading to decreased visual acuity and nystagmus. AAK, also referred to as aniridic keratopathy, manifests as corneal surface damage, epithelial thinning or loss, inflammation with immune cell infiltration, vascularization, and chronic progressive opacification. Methods: Twenty-one eyes in eighteen patients with aniridia underwent the triple procedure for visual rehabilitation. Subjects with stromal scarring with mild limbal deficiency were qualified for surgery. The majority of them developed stage II (15), and a few of them had third-degree (6) aniridic keratopathy. Results: The mean patient age was 38.4 ± 8.8. Visual acuity after one year of observation ranged from 0.4 in two eyes to 0.2 in nine eyes to below 0.1 in ten eyes. In the second year, VA remained at the same level in 13 patients (72.2%). In the third year, four patients (22.2%) experienced recurrence of AAK. Conclusions: A majority of the ARK cases (72.2%) had a graft providing useful vision for the patient 2 years after corneal transplantation, but the visual gain was modest at best. Longer follow-up time is required to evaluate functional graft outcomes.