title: Water flow conductivity and pore diameter in extended-wear gel lens materials.
abstract: The water flow conductivity of 3 high-water-content (70 to 85%) gel materials proposed for extended-wear contact lenses was measured. Pore diameter was calculated from these flow conductivities. High-water-content gels were found to have pore diameters in the range of 20 to 30 A compared with about 8 A for the lower-water-content HEMA gel. The larger pore diameter of extended-wear lenses will permit entry of drugs, hormones, and enzymes and thereby may pose new problems for wearers.
mesh_terms: D003263:Contact Lenses, Hydrophilic / Q000009:adverse effects / Q000592:standards*; D005782:Gels / Q000592:standards*; D006801:Humans; D010539:Permeability; D014867:Water
chemical_list: D005782:Gels; D014867:Water