Three month study of changes in the cornea after computer-determined and conventionally-determined contact lens fitting.

The conventional rigid-lens fitting method uses fluorescein to assess the tear layer beneath a trial lens on the corneal surface. A more advanced technique, which uses a computer program to determine the back surface specifications of a contact lens from a pre-set tear layer thickness, has been studied. No significant difference was found in terms of corneal physiological changes between the conventionally determined contact lenses and computer-determined contact lenses after a three-month wearing period. The results suggest that there is little difference in the two methods of fitting. However, the computer determined method was found to be more efficient in terms of chair time, and also can aid inexperienced rigid lens practitioners to select the appropriate lens back surface curves.