Contrast sensitivity after refractive lens exchange with a multifocal diffractive aspheric intraocular lens

Abstract

To evaluate distance and near contrast sensitivity (CS) under photopic and mesopic conditions before and after refractive lens exchange (RLE) and implantation of the aspheric AcrySofReSTOR (SN6AD3 model) intraocular lens (IOL). Seventy-four eyes of 37 patients after RLE underwent bilateral implantation with the aspheric AcrySof ReSTOR IOL. The patient sample was divided into myopic and hyperopic groups. Monocular uncorrected visual acuity at distance and near (UCVA and UCNVA, respectively) and monocular best corrected visual acuity at distance and near (BCVA and BCNVA, respectively) were measured before and 6 months postoperatively. Monocular CS function was measured at three different luminance levels (85, 5 and 2.5 cd/m²) before and after RLE. Post-implantation results at 6 months were compared with those found before surgery. Our results revealed that patients in both groups obtained good UCVA and BCVA after RLE at distance and near vision in relation to pre-surgery values. No statistically significant differences were found between the values of CS pre and post-RLE at distance and near, at any lighting condition and spatial frequency (p>0.002). Refractive lens exchange with aspheric AcrySof ReSTOR IOL in myopic and hyperopic population provided good visual function and yield good distance and near CS under photopic and mesopic conditions.