Changes in Accommodation and Ocular Aberration With Simultaneous Vision Multifocal Contact Lenses

Abstract

The aim of this study was to evaluate ocular aberration changes through different simultaneous vision multifocal contact lenses (CLs). Eighteen young-adult subjects with a mean age of 29.8±2.11 years took part. Changes in accommodative response, spherical aberration (C(4)(0)), horizontal coma (C(3)(1)), vertical coma (C(3)(-1)), and root mean square (RMS) of higher-order aberrations (HOAs, third to sixth orders) were evaluated. Measurements were obtained with a distance-single vision CL and 2 aspheric multifocal CLs of simultaneous focus center-near design (PureVision Low Add and PureVision High Add) for 2 accommodative stimuli (-2.50 and -4.00 D). All measurements were performed monocularly with a Hartmann-Shack aberrometer (IRX-3; Imagine Eyes, Orsay, France). No statistically significant differences were found in accommodative responses to -2.50- and -4.00-D stimuli between the single vision CL and the 2 multifocal CLs. Spherical aberration was found to decrease and become more negative with accommodation for both stimuli with all three CLs. Horizontal coma decreased significantly with accommodation (-2.5- and -4.00-D stimuli) for the distance-single vision CLs (P=0.002 and P=0.003). No differences were found in vertical coma Zernike coefficients. The RMS of HOAs was found to decrease only with the single vision CLs for both stimuli (P<0.01). Data obtained in this study suggest that in young subjects, the multifocal CLs studied do not induce large changes in accommodative response compared with the distance-single vision CLs. Spherical aberration reduced significantly with accommodation.