Comparison of changes in corneal thickness under low Dk and high Dk rigid contact lenses

In a randomised study, the relation between corneal thickness changes and Dk value of rigid gas permeable contact lenses was investigated in 10 volunteers. Each volunteer was fitted with lenses of different Dk values in each eye. A low Dk lens (Dk15) was fitted on one eye of each subject and a high Dk lens (Dk125) on the contralateral eye. After 2 months the reverse was done. After another 2 months, the lenses were again exchanged for the first pair. After each change corneal thickness was measured. A non-significant trend in corneal thickness was found in 13 of the 20 eyes. We conclude that for daily wear use the lower Dk materials meet corneal requirement.