Assessing The Utility of the Sunsoft Additions Multifocal Fitting Guide, by Sara L. Butterworth, O.D.

Title

Assessing The Utility Of The Sunsoft Additions Multifocal Fitting Guide

Author

Sara L. Butterworth, O.D.

Purpose

The Sunsoft Additions Multifocal hydrogel lens utilizes a center-near design in combination with three add powers (A: +1.25 and less, B: +1.50 to +2.00, and C: +2.25 and above) to allow the patient clear vision at both distance and near.  A retrospective study was performed to investigate whether the Additions fitting guide predicted the final distance power and add for patients fitted with the lenses.

Methods

Fifty-five eyes (28 patients) were evaluated in this study.  Each patient was fitted in the Additions lens based on the refractive recommendations from the manufacturer.  The lens powers at distance and near were modified based on patient feedback.  The vertex corrected spherical component of each patient’s spectacle prescription was compared to the final distance power prescribed in the contact lens.  The add power recommended by the fitting guide was compared to the final add prescribed in the contact lens.

Results

The final contact lens distance power was within +/-0.50 D of the vertexed spectacle sphere power in 92.7 percent of the eyes evaluated.  Additionally, the predicted contact lens add correlated at the 0.01 significance level with the final add prescribed.  Of the 14 eyes for which a C add was predicted, 42.9 percent were ultimately fitted with a B add.

Conclusion

Based on these results, the distance spectacle Rx was an excellent indicator of the distance power necessary in the contact lens.  A few patients, however, required over-plussing the distance Rx in the non-dominant eye to meet their needs.  The suggested add in the fitting guide was a reliable predictor of the strength of add required (A, B, or C).  The fitting guide recommendations that account for factors including working distance and occupation are supported by those patients initially fitted with the C add, but subsequently changed to a B add.