Rigid gas-permeable contact lenses in high and low humidity.

BACKGROUND

Contact lenses may alter tear film evaporation. Evaporation varies with respect to air temperature and relative humidity. Hence, tear evaporation may be a significant factor for many occupations, such as military pilots, in the arid environments in which they operate.

METHODS

The study tested rigid gas-permeable (RGP) contact lens wearer comfort and corneal staining in lower and higher relative humidity environments.

RESULTS

A trend was found that in a lower humidity environment, RGP contact lens comfort may decrease for some subjects. Corneal surface integrity was not compromised by the variation in relative humidity level, as determined by fluorescein dye analysis.

CONCLUSION

Within the range of humidity tested, for normal successful RGP patients, drier environments do not substantially reduce lens comfort.