Contrast Sensitivity with Center-distance Multifocal Soft Contact Lenses.

Abstract

The contrast sensitivity (CS) function provides a more detailed assessment of vision than visual acuity. It was found that center-distance multifocal contact lens designs that are increasingly being prescribed for myopia control reduce distance photopic and mesopic CS in nonpresbyopic patients across a range of spatial frequencies. This study aimed to determine the effect of center-distance multifocal soft contact lenses (MFCLs) on CS under photopic and mesopic conditions in nonpresbyopic patients. Twenty-five myopic, nonpresbyopic adults were fitted binocularly with three lenses: Biofinity single vision contact lens (SVCL), Biofinity Multifocal D +2.50 add, and NaturalVue Multifocal in random order. Contrast sensitivity was measured at distance (4 m) under photopic and mesopic conditions and at near under photopic conditions. Log CS by spatial frequency and area under the log contrast sensitivity function (AULCSF) were analyzed between lenses. Distance photopic CS at each spatial frequency was higher with the SVCL than the MFCLs (P < .001), but there was no difference between the MFCLs (P = .71). Distance mesopic CS from 1.5 to 12 cycles per degree (cpd) was higher with the SVCL than the MFCLs (all P < .02); however, at 18 cpd, there was no difference in CS between NaturalVue and the SVCL (P = .76), possibly because of spurious resolution. Photopic AULCSF for the SVCL was roughly 10% greater than both MFCLs. Contrast sensitivity at near was generally similar between lenses, only slightly lower with the NaturalVue at 11 and 15.5 cpd, but AULCSF at near was not different between lenses (P > .05). Multifocal contact lenses reduce distance contrast sensitivity under both photopic and mesopic conditions. There is no clinically significant difference in near CS among all three lenses. These data show that MFCLs have effects on vision that are not captured by standard high-contrast visual acuity testing.