Effects of novel multifocal soft contact lens on peripheral refraction of myopic eyes when looking at distant and near targets

Abstract

Background It is generally accepted the association between hyperopic peripheral defocus and myopia progression. To search for a good optical method to slow the myopia progression for the children who need long-time near work, we compared the effects of novel multifocal soft contact lenses (MFSCLs) with single vision soft contact lenses (SVSCLs) on peripheral refraction when looking at both distant and near targets. Methods The refraction of 25 young myopic subjects’ right eye were measured at horizontal retina eccentricities in 10º steps from 30º temporal to 30º nasal, with no correction (baseline), novel MFSCLs and SVSCLs when looking at distant (5 m) and near (0.4 m) targets. Results Subjects wearing MFSCLs presented significantly more myopic relative peripheral refractive error (RPRE) profile than SVSCLs at all horizontal retina eccentricities when looking at distant targets (all p<0.01). Compared with looking at distant targets, subjects wearing SVSCLs or MFSCLs showed a hyperopic shift of peripheral defocus when looking at near targets, owning to the effects of accommodative lag and hyperopic RPRE change during accommodation (except T20º and T30º wearing SVSCLs and N30º wearing MFSCLs, p=0.822, p=0.950, p=0.390, respectively, all other eccentricities p<0.05). But subjects wearing MFSCLs could still maintain a certain magnitude of myopic peripheral defocus at horizontal retina eccentricities when looking at near targets (T20° and T30°, p=0.023 and p<0.001, respectively). Conclusions The novel MFSCLs imposed strong myopic peripheral defocus when looking at distant targets. They also maintain a certain magnitude of myopic peripheral defocus when looking at near targets, regardless of the hyperopic effect of accommodation lag and hyperopic shift in RPRE during accommodation.