RESUMO
PURPOSE: The goal of this study was to assess the efficacy and safety of inferior implantation of the Xen Gel 45® Stent in a cohort of refractory glaucoma patients who had undergone multiple failed procedures and lacked healthy superior conjunctiva. PATIENTS AND METHODS: We retrospectively included individuals with refractory glaucoma who underwent implantation of a Xen 45® in the inferior quadrants of the conjunctiva. At the 12-month mark, two success criteria were assessed: "Complete" success, defined as an intraocular pressure (IOP)≤21mmHg with a≥20% reduction in IOP without additional IOP-lowering medications, the absence of a requirement for additional filtering surgery, and the absence of chronic hypotony; and "Qualified" success, which consisted of patients meeting the same criteria but requiring glaucoma medications postoperatively. Safety was also monitored throughout the 12-month follow-up. RESULTS: A total of 35 patients who underwent inferior Xen implantation were assessed. After 12months, 20 patients (57.1%) achieved qualified success, with twelve patients (34.3%) attaining complete success. Excluding five patients who underwent additional filtering surgery during follow-up, the mean IOP decreased significantly from 30.73±9.7mmHg to 16.49±7.9mmHg, representing a mean decrease of 14.24±12.13mmHg (46.5%; P<0.0001). The mean number of medications at 12months decreased from 3.43±1.6 to 1.53±1.52 (-55.4%; P<0.0001). The mean number of needlings was 1.29±1.2. Implant exposure was observed in two patients during the first postoperative month. CONCLUSIONS: Inferior placement of Xen appears to be a viable treatment option for patients with refractory glaucoma and a history of multiple failed glaucoma procedures. It demonstrates both significant efficacy and acceptable safety.
RESUMO
The corneal epithelium is one of the first tissue barriers of the eye against the environment. In recent years, many studies provided better knowledge of its healing, its behavior and its essential role in the optical system of the eye. At the crossroads of basic science and clinical medicine, the study of the mechanical stresses applied to the cornea makes it possible to learn the behavior of epithelial cells and better understand ocular surface disease. We describe herein the current knowledge about the adhesion systems of the corneal epithelium and their resistance to mechanical stress. We will also describe the involvement of these mechanisms in corneal healing and their role in epithelial dynamics. Adhesion molecules of the epithelial cells, especially hemidesmosomes, allow the tissue cohesion required to maintain the integrity of the corneal epithelium against the shearing forces of the eyelids as well as external forces. Their regeneration after a corneal injury is mandatory for the restoration of a healthy epithelium. Mechanotransduction plays a significant role in regulating epithelial cell behavior, and the study of the epithelium's response to mechanical forces helps to better understand the evolution of epithelial profiles after refractive surgery. A better understanding of corneal epithelial biomechanics could also help improve future therapies, particularly in the field of tissue engineering.
