Purpose. To compare peripheral lower and higher order aberrations across the horizontal (±40°) and inferior (−20°) visual fields in healthy groups of young and old emmetropes.
Methods. We have measured off-axis aberrations in the groups of 30 younger (24 ± 3 years) and 30 older (58 ± 5 years) emmetropes. The aberrations of OD were measured using the COAS-HD VR Shack-Hartmann aberrometer in 10° steps to ±40° horizontally and −20° inferiorly in the visual field. The aberrations were quantified with Zernike polynomials for a 4 mm pupil diameter. The second-order aberration coefficients were converted to their respective refraction components (M, J45, and J180). Mixed between-within subjects, analysis of variance were used to determine whether there were significant differences in the refraction and aberration components for the between-subjects variable age and the within-subjects variable eccentricity.
Results. Peripheral refraction components were similar in both age groups. Among the higher order coefficients, horizontal coma (C31) and spherical aberration (C40) varied mostly between the groups. Coma increased linearly with eccentricity, at a more rapid rate in the older group than in the younger group. Spherical aberration was more positive in the older group compared with the younger group. Higher order root mean square increased more rapidly with eccentricity in the older group.
Conclusions. Like the axial higher order aberrations, the peripheral higher order aberrations of emmetropes increase with age, particularly coma and spherical aberration.
Vision Enabling Laboratory, Section of Optometry and Vision Science, School of Natural Sciences, Linnaeus University, Kalmar, Sweden (KB, JG), and Biomedical and X-Ray Physics, Royal Institute of Technology (KTH), Stockholm, Sweden (PU).
This research was supported by the Faculty of Natural Sciences and Technology, Linnaeus University, Kalmar, and the foundation Sparbanksstiftelsen Kronan.
Received December 29, 2010; accepted April 21, 2011.
Karthikeyan Baskaran, Vision Enabling Laboratory, Section of Optometry and Vision Science, School of Natural Sciences, Linnaeus University, 391 82 Kalmar, Sweden, e-mail: firstname.lastname@example.org