Base curve influence on the fitting and comfort of the senofilcon a contact lens

Resum

Purpose. To determine the influence of the base curve on the movement, on the corneal surface mechanical alterations and on the subjective comfort of Senofilcon A contact lens for corneas having central curve radius flatter than 7.80mm. Methods. In this prospective, double-masked, contralateral, randomized study, 40 eyes of 20 participants, with keratometric readings above 7.80mm, were randomly fitted with Senofilcon A contact lenses: one having an 8.80mm base curve in one eye and another one having 8.40mm base curve in the other eye. Lens movement, corneal surface mechanical alterations and comfort were assessed in both eyes 15 days after contact lens fitting. Results. At 15 days of contact lens fitting, no statistically significant differences were found regarding lens movement between the lens with the 8.40mm base curve and the lens with the 8.80mm base curve. There were not statistically significant differences between groups neither in peripheral nor in central staining, and absence of clinical significance was found. There was a statistically significant difference on comfort rate between the lenses. The mean comfort score for the 8.80mm base curve was 3.5±0.92, whereas for the 8.40mm base curve it was 4.39±0.5 (P<0.001). Conclusions. In corneas with keratometry flatter than, 7.80mm, 8.80 and 8.40mm base curves, show acceptable fitting characteristics. Nevertheless, 8.40mm base curve is more comfortable than 8.80mm base curve. These results suggest that silicone hydrogel soft contact lenses may require steeper base curve selection criteria than the conventional hydrogel soft lenses in order to improve the comfort.