An Optimized Method to Produce Human-Induced Pluripotent Stem Cell-Derived Limbal Stem Cells Easily Adaptable for Clinical Use.

In adults, the limbal stem cells (LSC) reside in the limbal region of the eye, at the junction of the cornea and the sclera where they renew the outer epithelial layer of the cornea assuring transparency. LSC deficiencies (LSCD) due to disease or injury account for one of the major causes of blindness. Among current treatments for LSCD, cornea transparency can be restored by providing new LSC to the damaged eye and induced pluripotent stem cells (iPSC) holds great promise as a new advanced cell source.

Intereye Asymmetry as a Predictor of Progression in Patients With Untreated Keratoconus: Findings From a Longitudinal Study.

Purpose: The purpose of this study was to evaluate interocular predictors of progression in patients with untreated keratoconus.

Methods: This is a multicenter longitudinal observational study with real-world data collected through the Save Sight Keratoconus Registry. Patients between the period of June 2000 and September 2022 were included in this study.

Herpes Zoster Ophthalmicus: Presentation, Complications, Treatment, and Prevention.

Herpes zoster (HZ) is caused by reactivation of latent infection of varicella zoster virus (VZV) in sensory (cranial, dorsal root) ganglia. Major risk factors for HZ are increasing age and immunosuppression. HZ ophthalmicus (HZO) is a subset of HZ with involvement of the ophthalmic division of the fifth cranial trigeminal nerve.

Systemic treatment and surgical intervention in inflammatory Terrien disease.

This case report presents a unique instance of a 55-year-old male patient exhibiting features of both Terrien marginal degeneration (TMD) and Fuchs' superficial marginal keratitis. Characterized by peripheral corneal thinning vascularization, and a pseudopterygium, the patient experienced recurrent photophobia, redness, and tearing over 15 years. This case challenges the traditional distinction between TMD and Fuchs' superficial marginal keratitis, suggesting a potential common underlying disorder.

Influence of Keratoconus Severity on Detecting True Progression with Scheimpflug Imaging and Anterior Segment Optical Coherence Tomography.

To determine consistent change over time in keratoconus disease, it is necessary to establish progression cut-off values based on intersession variability of the device used to monitor the cornea. The aim of this study was to analyze the accuracy of corneal parameters using Scheimpflug tomography and anterior segment optical coherence tomography in healthy and keratoconic eyes of varying severity to determine the cut-off values that indicate real progression. Three repeated measurements of each cornea of healthy (20 eyes) and keratoconic eyes (mild = 16, moderate = 25 and severe = 20) were recorded using Pentacam and Casia SS-1000 devices, which were repeated 2-3 weeks later.

Detecting True Change in Keratoconus after Intracorneal Ring Segment Implantation.

Confirming the progression of keratoconus is of paramount relevance to providing the appropriate treatment. Real change should be considered consistent over time. It must be greater than the variability of the measurement of the device used to monitor the cornea.

Derivation of Limbal Stem Cells from Human Adult Mesenchymal Stem Cells for the Treatment of Limbal Stem Cell Deficiency.

Approximately 10 million individuals have blindness due to limbal stem cell (LSCs) deficiency, one of the most challenging problems in ophthalmology. To replenish the LSC pool, an autologous extraocular cell source is appropriate, thereby avoiding the risk of immune rejection, the need for immunosuppression and the risk of damaging the contralateral eye. In recent years, adipose-derived mesenchymal stem cells (ADSCs) have been a key element in ocular regenerative medicine.

Five-year corneal cross-linking outcomes: A Save Sight Keratoconus Registry Study.

Background: We aimed to determine the long-term outcomes of epithelium-off cross-linking (CXL) in keratoconus patients.

Methods: An observational registry study from 41 centres across 5 countries was carried out. Primary outcomes included the mean change in visual acuity (VA), Kmax, K2, and thinnest corneal thickness (TCT) at 1-5 years.

Corneal Regeneration Using Adipose-Derived Mesenchymal Stem Cells.

Adipose-derived stem cells are a subtype of mesenchymal stem cell that offers the important advantage of being easily obtained (in an autologous manner) from low invasive procedures, rendering a high number of multipotent stem cells with the potential to differentiate into several cellular lineages, to show immunomodulatory properties, and to promote tissue regeneration by a paracrine action through the secretion of extracellular vesicles containing trophic factors. This secretome is currently being investigated as a potential source for a cell-free based regenerative therapy for human tissues, which would significantly reduce the involved costs, risks and law regulations, allowing for a broader application in real clinical practice. In the current article, we will review the existing preclinical and human clinical evidence regarding the use of such adipose-derived mesenchymal stem cells for the regeneration of the three main layers of the human cornea: the epithelium (derived from the surface ectoderm), the stroma (derived from the neural crest mesenchyme), and the endothelium (derived from the neural crest cells).

Quality of life impact of eye diseases: a Save Sight Registries study.

Background: The objectives of this study were to evaluate the quality-of-life (QoL) impact of eye diseases (keratoconus; neovascular age-related macular degeneration, AMD; retinal vein occlusion, RVO; and diabetic macular edema, DME) using the Impact of Vision Impairment (IVI) questionnaire, and to determine the relationship between the IVI scores and visual acuity.

Methods: This cross-sectional, multicentre, real-world study utilised the prospective, web-based Save Sight Registries. The IVI was completed by 1557 patients: 307 with keratoconus, 1049 with AMD, 148 with RVO and 53 with DME.

Improvement of an Effective Protocol for Directed Differentiation of Human Adipose Tissue-Derived Adult Mesenchymal Stem Cells to Corneal Endothelial Cells.

Corneal disease affects 12.5 million individuals worldwide, with 2 million new cases each year. The standard treatment consists of a corneal transplantation from a human donor; however, the worldwide demand significantly exceeds the available supply.

A Risk Prediction Model for Endothelial Keratoplasty After Uncomplicated Cataract Surgery in Fuchs Endothelial Corneal Dystrophy.

Purpose: To develop a risk prediction model for endothelial keratoplasty (EK) after uncomplicated cataract surgery in Fuchs endothelial corneal dystrophy (FECD) using Scheimpflug imaging.

Design: Prospective, observational cohort study.

Methods: The study was conducted at the Ramón y Cajal University Hospital (Madrid, Spain) on 127 eyes from 93 consecutive patients with vision loss, FECD, and cataracts.

Priming human adipose-derived mesenchymal stem cells for corneal surface regeneration.

Limbal stem cells (LSC) maintain the transparency of the corneal epithelium. Chemical burns lead the loss of LSC inducing an up-regulation of pro-inflammatory and pro-angiogenic factors, triggering corneal neovascularization and blindness. Adipose tissue-derived mesenchymal stem cells (AT-MSC) have shown promise in animal models to treat LSC deficiency (LSCD), but there are not studies showing their efficacy when primed with different media before transplantation.

Predictors of progression in untreated keratoconus: a Save Sight Keratoconus Registry study.

Aims: We set out to identify risk factors for progression in untreated keratoconus patients from 34 centres across Australia, New Zealand, Spain and Italy.

Methods: Patients were divided into 'progressors' and 'stable' patients for each clinical parameter: visual acuity (VA), steepest keratometry (maximum keratometry (Max-K)) and thinnest corneal thickness (TCT). Primary outcomes were the proportion of eyes with sustained progression in VA, Max-K or TCT within 3 years.

Corneal Stroma Regeneration: New Approach for the Treatment of Cornea Disease.

Corneal grafting is one of the most common forms of human tissue transplantation. The corneal stroma is responsible for many characteristics of the cornea. For these reasons, an important volume of research has been made to replicate the corneal stroma in the laboratory to find an alternative to classical corneal transplantation techniques.

Corneal stroma regeneration: Preclinical studies.

Corneal grafting is one of the most common and successful forms of human tissue transplantation in the world, but the need for corneal grafting is growing and availability of human corneal donor tissue to fulfill this increasing demand is not assured worldwide. The stroma is responsible for many features of the cornea, including its strength, refractive power and transparency, so enormous efforts have been put into replicating the corneal stroma in the laboratory to find an alternative to classical corneal transplantation. Unfortunately this has not been yet accomplished due to the extreme difficulty in mimicking the highly complex ultrastructure of the corneal stroma, and none of the obtained substitutes that have been assayed has been able to replicate this complexity yet.

Epidemiology of pseudomembranous conjunctivitis in a tertiary hospital: A 2-year retrospective study.

Purpose: To describe the incidence, duration, and complication rate of patients with a clinical diagnosis of pseudomembranous viral conjunctivitis.

Methods: A retrospective observational study is performed compiling the data of patients diagnosed as pseudomembranous conjunctivitis at the hospital's emergency department from June 2016 to May 2018. Demographic variables, duration of symptoms, and follow-up until resolution of the pseudomembranes and associated complications are collected.

Corneal graft failure: an update.

Corneal graft surgery is one of the most successful forms of human solid-tissue transplantation, and nowadays, there is a worldwide expansion of the surgical volume of corneal grafts. This surgery is continuously evolving, with new surgical techniques and postoperative treatments that have considerably increased the chance of survival for the grafts. Despite the high rate of success, corneal transplantation is still complicated by a relevant risk of graft failure.

Characteristics, Behaviors, and Awareness of Contact Lens Wearers Purchasing Lenses Over the Internet.

Objectives: To describe the characteristics and hygiene habits of contact lens (CL) wearers who acquire CLs over the Internet, as well as their awareness of modifiable risk factors (RFs).

Methods: A web-based survey was conducted among clients of an online CL sales platform during 6 months. Demographic data, CL hygiene-related awareness, and compliance were collected and analyzed.

Artificial neural network to guide intracorneal ring segments implantation for keratoconus treatment: a pilot study.

Background: To analyze the clinical results of an artificial neural network (ANN) that has been processed in order to improve the predictability of intracorneal ring segments (ICRS) implantation in keratoconus.

Methods: This retrospective, comparative, nonrandomized, pilot, clinical study included a cohort of 20 keratoconic eyes implanted with intracorneal ring segments KeraRing (Mediphacos, Belo Horizonte, Brazil) using the ANN (ANN group) and 20 keratoconic eyes implanted with KeraRing using the manufacturer's nomograms (nomogram group). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA) (visual acuity is expressed in decimal value and in LogMAR value in brackets), manifest refraction, corneal topography, tomography, aberrometry, pachymetry and volume analysis (Sirius System.

Treatment of corneal endothelial damage in a rabbit model with a bioengineered graft using human decellularized corneal lamina and cultured human corneal endothelium.

Objective: We aimed to investigate the functionality of human decellularized stromal laminas seeded with cultured human corneal endothelial cells as a tissue engineered endothelial graft (TEEK) construct to perform endothelial keratoplasty in an animal model of corneal endothelial damage.

Methods: Engineered corneal endothelial grafts were constructed by seeding cultured human corneal endothelial cell (hCEC) suspensions onto decellularized human corneal stromal laminas with various coatings. The functionality and survival of these grafts with cultured hCECs was examined in a rabbit model of corneal endothelial damage after central descemetorhexis.

Preoperative Risk Assessment for Progression to Descemet Membrane Endothelial Keratoplasty Following Cataract Surgery in Fuchs Endothelial Corneal Dystrophy.

Purpose: To identify preoperative corneal tomographic features that predict progression to endothelial keratoplasty (EK) following cataract surgery in Fuchs endothelial corneal dystrophy (FECD) and establish a regression model to identify high-risk patients.

Design: Prospective, observational cohort study.

Methods: Setting: Hospital Universitario Ramón y Cajal, Madrid, Spain.

Keratometric, Pachymetric, and Surface Elevation Characterization of Corneas With Fuchs Endothelial Corneal Dystrophy Treated With DMEK.

Purpose: To characterize pachymetric, keratometric, and surface elevation parameters in pseudophakic eyes with Fuchs dystrophy that underwent Descemet membrane endothelial keratoplasty (DMEK) and to compare these characteristics with those in normal pseudophakic eyes.

Methods: Postoperative corneal tomography with a median follow-up of 20 months was evaluated using the Pentacam tomographer on 46 DMEK eyes. Results were compared with data from an age-matched cohort of 46 normal eyes.

Repeatability and Intersession Reproducibility of Pentacam Corneal Thickness Maps in Fuchs Dystrophy and Endothelial Keratoplasty.

Purpose: To assess intrasession repeatability and intersession reproducibility of Pentacam corneal thickness maps in patients with Fuchs endothelial corneal dystrophy (FECD) before and after endothelial transplantation.

Methods: In this observational diagnostic evaluation, 20 healthy subjects along with 81 consecutive patients were examined. Patients were classified into 4 groups: FECD without corneal edema, FECD with corneal edema, Descemet stripping automated endothelial keratoplasty, and Descemet membrane endothelial keratoplasty.