Abstract
Purpose: :
During contact lenses wear, tear film containing proteins, lipids, and possibly microorganisms cover the surface of contact lenses. The tear film deposits, especially during extended or continuous wear, result in lens dryness and discomfort that often leads users to seek other methods of vision correction. Multipurpose solutions have been developed to clean and remove these deposits and disinfect contact lenses between wearing cycles. We formulated a multi–purpose eye drop (MPD) based on MoistureLoc® technology, a mixture of a cationic cellulosic polysaccharide (Polyquaternium 10) and a polymer surfactant (Poloxamer 407) with deposit management and capabilities, to enhance comfort during extended lens wear of silicone hydrogel lenses.
Methods: :
The newly formulated MPD was evaluated based on in vitro methods for its capacity to manage (by preventing, cleaning and/or reducing) lipid and protein deposits on the surface of silicone hydrogel and hydrogel contact lenses. Lipid uptake and lipid solubilization assays were performed with GC and spectrophotometery. Protein management assays (stabilization, cleaning and prevention) were performed based on a modification of previously described Micrococcus Luteus assay (Senchyna et al. Curr Eye Res 2004; 28:25–36) and quantitative image analysis. Phosphate buffered Saline (PBS) was used as a control solution
Results: :
Based on our models, in vitro protein and lipid deposition on silicone hydrogel and hydrogel lenses were both significantly reduced (p <0.05) compared to the control group, when lenses were tested with the newly formulated MPD.
Conclusions: :
The newly formulated MPD, significantly reduced the degree of tear film (protein and lipid) deposition on the surface of silicone hydrogel and hydrogel contact lenses. Managing the tear film deposition on contact lenses has been suggested as a strategy for increasing comfort and healthier lens wear.
Keywords: contact lens • cornea: tears/tear film/dry eye