Clinical Research Directory

A Single-Center Clinical Study to Evaluate the Efficacy and Safety of Autologous Urine-Derived Epithelial Cells in the Treatment of Corneal Endothelial Cell Dysfunction

Corneal endothelial cell dysfunction is usually a corneal disease caused by damage or loss of corneal endothelial cells. It is characterized by corneal edema, opacity, and subepithelial bullae, leading to pain, blurred vision, or even blindness. Conventional treatments usually involve allogeneic corneal transplantation or corneal endothelial transplantation. Anterior chamber cell transplantation is a breakthrough treatment for corneal endothelial diseases developed in recent years. Autologous urine-derived epithelial cells greatly reduce the risk of immune rejection and the use of anti-rejection drugs, avoiding reliance on and waiting for corneal donors.

Effects of Topical Insulin on Corneal Epithelium Healing After Corneal Crosslinking in Patients With Keratoconus

The cornea plays a fundamental role in vision, being a complex tissue essential for ocular health. In ophthalmological practice, there are situations such as corneal crosslinking, where damage to the corneal epithelium occurs. Crosslinking is a surgical procedure aimed at strengthening collagen bonds in the corneal stroma to prevent the progression of keratoconus, through the application of topical riboflavin followed by ultraviolet (UV-A) radiation. To enhance the effectiveness of riboflavin and UV-A radiation, the corneal epithelium needs to be removed, which can cause postoperative pain and discomfort, as well as increase the risk of complications such as infections, scarring, corneal opacities, perforations, and recurrent epithelial erosions. Several growth factors play a role in epithelial healing, and the discovery of insulin in the tear film and the presence of insulin and Insulin-Like Growth Factor (IGF-1) receptors in the cornea has raised the hypothesis that insulin may modulate the cornea's wound healing response. Since then, topical insulin has been used for various ocular pathologies, including dry eye disease, persistent epithelial defects, and neurotrophic ulcers. Based on this knowledge, studies have been developed, and promising results regarding the use of insulin in corneal healing have been reported, providing a scientific foundation for the realization of this project. The objective of this study is to evaluate the effect of insulin eye drops at a concentration of 50 IU/ml on epithelial healing in non-diabetic patients undergoing epithelial debridement for corneal crosslinking. To this end, a randomized, double-masked clinical trial will be conducted with two groups, one being the control group, in which researchers will compare the epithelial healing rate in mm²/h between the insulin group and the placebo group, as the primary outcome. Patients diagnosed with keratoconus and with an indication for the crosslinking procedure, will be invited to participate. As a result of the study, it is expected to assess and quantify the impact of topical insulin on epithelial defect closure in patients undergoing crosslinking, compared to placebo. Topical insulin may contribute to early epithelial defect closure, control of inflammation, and prevention of complications that could significantly impact visual quality.

The Role of Transscleral Cyclophotocoagulation in Patients Undergoing a Boston Keratoprosthesis

The Boston keratoprosthesis (KPro) is a special plastic device that is used to replace a sick cornea (transparent part of the eye, in front of the iris) in order to restore vision in patients who have failed traditional corneal transplants or have a very poor prognosis of success. Glaucoma is a chronic disease which causes optic nerve damage secondary to high pressure inside the eye and could lead to vision loss in the long term. Glaucoma is highly prevalent in patients who require a KPro and even more after their procedure. In order to decrease the intra-ocular pressure, surgeons can use multiple eyedrops. Unfortunately, following the KPro surgery, eyedrops lose their efficiency because they are less absorbed by the eye. The transscleral cyclophotocoagulation (TS-CPC) is a laser treatment used in advanced refractory glaucoma. This laser helps decrease the intra-ocular pressure and have a better control of the disease. There are different methods of laser transmission, including the continuous transmission (G-Probe) and the micro-pulsation method (Micopulse). Given the high prevalence of glaucoma in patients receiving a KPro, the investigators are studying the effect of giving the TS-CPC treatment prophylactically to patients before their Boston keratoprosthesis. Our hypothesis is that prophylactic TS-CPC will decrease glaucoma progression as well as the risks of developing glaucoma following the Boston keratoprosthesis . METHOD The investigators aim to recruit twenty (20) patients who are scheduled to receive Boston KPro. Participants will be randomized into two groups: 1) Groupe 1 will receive a prophylactic treatment of transscleral cyclophotocoagulation a G-Probe. 2) Groupe 2 will receive a prophylactic treatment of transscleral cyclophotocoagulation with a micropulse transmission (MicroPulse). The patients will receive their laser treatment by a glaucoma specialist 4 to 8 weeks before their KPro surgery. One week following their laser treatment, the participants will be examined by their glaucoma specialist. Following their KPro surgery, patients will have a follow-up at day-1, weeks 1 and 2, months 1 and 3, then every 4 to 6 months for 5 years. Additional non-invasive glaucoma tests will be performed twice during the first 3 months following the surgery and will be repeated every 4-6 months. Visual acuity results, the visual field tests and rates of post-operative complications will be compared between the different groups.