Ocular surface epithelium and tear film

The Ocular surface epithelium and tear film is a dynamic and highly integrated system consisting of the tissue layers at the front of the eye—primarily the corneal and conjunctival epithelium—overlain by the tear film, a structured multilayered fluid. The tear film itself has three layers: a superficial lipid layer that retards evaporation, an intermediate aqueous layer with proteins and electrolytes providing nourishment and immune protection, and an inner mucin layer that anchors the tear film to the epithelium and acts as a physical barrier. This unit is essential for visual clarity, mechanical and immune defense against environmental insults, and functional homeostasis of the eye. Disruption of its integrity—whether by reduced secretion, altered composition, or epithelial injury—underlies various diseases including dry eye, infection, and inflammation.

Other names

Ocular surfaceOcular surface tissuesTear filmTear layerOcular surface and tear film

Replace or supplement deficient tear components; Enhance lubrication and/or epithelial healing; Reduce surface inflammation (anti-inflammatory action); Increase mucin or lipid secretion; Protect against microbial infection (antibiotic action)