Effect of Artificial Tear Formulations on the Metabolic Activity of Human Corneal Epithelial Cells after Exposure to Desiccation.

Artificial lipid-containing tear formulations are developed to reduce tear evaporation by the restoration of a deficient tear lipid layer. Artificial tear formulations that prevent cell desiccation will result in ocular surface protection and the maintenance of cell metabolic activity. During dehydration, cells undergo the process of loss of metabolic activity and subsequently cell death.

Kinetic Deposition of Polar and Non-polar Lipids on Silicone Hydrogel Contact Lenses.

: This study investigated kinetic lipid uptake to four silicone hydrogel (SiHy) lenses over a period of four weeks, using an radiolabel method. : Four contemporary monthly replacement SiHy lenses (lotrafilcon B, senofilcon C, comfilcon A, samfilcon A) were incubated in three different solutions: 1) An artificial tear solution (ATS) containing C-labeled phosphatidylcholine (PC), 2) an ATS containing C-cholesteryl oleate (CO) and 3) an ATS containing four C-radiolabeled lipids (PC, phosphatidylethanolamine, CO, and cholesterol (total lipid)). After 16 hours, lipids were extracted twice from the lenses with chloroform:methanol and the radioactive counts determined the lipid quantities to simulate 1 day of wear.