Empirical Fitting With Polycon II Lenses, by Herman Kwong, O.D., and Ralph Gundel, O.D., F.A.A.O.

Title

Empirical Fitting with Polycon II Lenses

Authors

Author:  Herman Kwong, O.D., Ralph Gundel, O.D., FAAO

Purpose/

Methods

Obtaining both good vision and eye health with Rigid Gas Permeable (RGP) lenses has traditionally been accomplished through diagnostic fitting.  Proponents of diagnostic lens fitting philosophy believe the trial fitting process allows the clinician to account for individual corneal differences and increases the likelihood of a successful lens fit, thus providing better patient satisfaction.  However, diagnostic fitting requires the practitioner to spend more time in lens selection that may be accomplished just as easily through empirical fitting.  The appearance of a diagnostic lens on a patient may also present differently due to potential variations in lens power, exact base curve and diameter combination as required by the original lens.  In addition, empirical fitting has the benefit of reducing chair time thus giving the practitioner more time with existing or new patients.  A clinical evaluation was undertaken to determine the success rate of empirical fitting 9.0mm Polycon II lenses based on manufacturing guidelines in achieving optimal vision, comfort and ocular health.

Results

The results of the study support the success of empirical fitting with regard to determining refractive power and correcting for up to 2.00D of corneal astigmatism.  Although the current manufacturer’s fitting protocol calls for an interpalpebral fit with a 9.0mm lens, this fit was not achieved clinically.