Dot matrix stabilization with the piggyback lens system.

BACKGROUND

The piggyback system of contact lens correction is used in specialized cases to provide corneal protection with the soft lens and optical correction with a rigid gas-permeable lens. Controlling the position and amount of movement of the RGP lens over the soft lens is a critical factor in fitting the piggyback system.

METHODS

The movement of rigid gas-permeable lenses as part of a piggyback system was investigated under two different conditions. The RGP lens was placed on a smooth-surface soft lens and compared to a RGP lens placed on a dot matrix designed front-surface soft lens.

RESULTS

When placed over a dot matrix front-surface soft lens, the RGP lens moved significantly less than when placed on the front surface of a smooth-surface soft lens.

CONCLUSIONS

This controlled movement can increase patient comfort and reduce RGP slippage and lens dislocation when the piggyback lens system is prescribed.