👁️ Mechanism and Application of Corneal Cross-Linking (CXL) Devices
Corneal Cross-Linking (CXL) Devices are ophthalmologic instruments used to perform a minimally invasive procedure designed to increase the mechanical strength and stiffness of the cornea, the transparent front part of the eye. This procedure is a vital treatment to halt the progression of corneal ectatic disorders, most notably keratoconus, where the cornea progressively thins and bulges outward.
Mechanism of Action: CXL is a photo-polymerization process mediated by the combined action of a photosensitizing agent (usually Riboflavin, or Vitamin B2) and Ultraviolet A (UVA) light (typically 370 nm).
Riboflavin Instillation: Riboflavin drops are applied topically to the corneal surface. Riboflavin acts as a photosensitizer and a UV filter, protecting the deeper, sensitive structures of the eye (like the endothelium and lens).
UVA Irradiation: The CXL device delivers a controlled beam of UVA light. The UVA light activates the riboflavin, which then produces Reactive Oxygen Species (ROS), primarily singlet oxygen.
Cross-Link Formation: These ROS initiate the formation of…