Objective: The aim of this study was to evaluate ocular aberration changes through different simultaneous vision multifocal contact lenses (CLs).
Methods: Eighteen young-adult subjects with a mean age of 29.8±2.11 years took part. Changes in accommodative response, spherical aberration (
), horizontal coma (
), vertical coma (
), 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).
Results: 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).
Conclusions: 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.
Optometry Research Group (GIO) (J.R.-A., D.M.-C., T.F.-B., R.M.-M.), Optics Department, University of Valencia, Valencia, Spain; Optics and Optometry Department (J.R.-A.), Universidad Europea de Madrid, Madrid, Spain; Faculty of Life Sciences (H.R.), University of Manchester, Manchester, United Kingdom.
Address correspondence and reprint requests to Javier Ruiz-Alcocer, Ph.D., Optometry Research Group, Optics Department, University of Valencia, Spain; e-mail: firstname.lastname@example.org
Supported in part by a Ministerio de Ciencia e Innovación Research Grants (#SAF2008-01114# and SAF 2009-13342) and José Castillejo scholarship to Robert Montés-Micó.
The authors have no proprietary interest in any of the materials mentioned in this article.
Accepted June 18, 2012