Corneal epithelial permeability and daily contact lens wear as determined by fluorophotometry

The condition of the corneal epithelium of 57 non-, 18 soft-, 29 gas-permeable- and 26 hard contact lens-wearing eyes was investigated by fluorophotometric determination of the corneal epithelial permeability. The mean permeability values for non-, soft-, gas-permeable- and hard contact lens-wearing eyes were 0.040 nm/s +/- 0.017 SD, 0.024 nm/s +/- 0.009 SD, 0.028 nm/s +/- 0.017 SD and 0.044 nm/s +/- 0.020 SD, respectively. The mean permeability values for soft and gas-permeable contact lens-wearing eyes were significantly lower than that for non contact lens-wearing eyes (-40%, p less than 0.001 and -30%, p less than 0.005); no significant difference was found between the mean values for hard and non contact lens-wearing eyes (p = 0.38).