Higher order aberrations in a normal adult population

Purpose: to determine the distribution of zernike coefficients and higher order aberrations in a normal population and its relationship with age,gender,biometric components,and spherical equivalent. methods: during the first phase of the shahroud cohort study,6311 people of the 40-64-year-old population of shahroud city were selected through random cluster sampling. a subsample of participants was examined with zywave aberrometer (the bausch & lomb,rochester,ny) to measure aberrations. measurements of aberrations were done before cycloplegic refraction,and values generated from a minimum pupil diameter of 5 mm were reported in this analysis. results: after applying exclusion criteria,904 eyes of 577 people were analyzed in this study and mean age in this study was 49.5 ± 5.7 years and 62.9% were female. mean root-mean-square (rms) of the third-,fourth-,and fifth-order aberrations was 0.194 μm (95%ci: 0.183 to 0.204),0.115 μm (95%ci: 0.109 to 0.121),and 0.041 μm (95%ci: 0.039 to 0.043),respectively. total rms coma (z3 -1,z3 1,z5 -1,z5 1),total rms trefoil (z3 -3,z3 3,z5 -3,z5 3),and spherical aberration (z4 0) in the studied population was 0.137 μm (95% ci:0.129-0.145),0.132 μm (95% ci: 0.123-0.140),and -0.161 μm (95%ci:-0.174 to -0.147),respectively. mean higher-order zernike rms in this study was 0.306 (95% ci: 0.295-0.318) micrometer,and in the multiple model,it significantly correlated with older age and short axial length. the highest amounts of higher-order rms were observed in hyperopes,and the smallest in emmetropes. increased nuclear opacity was associated with a significant increase in ho rms (p < 0.001). analysis of zernike coefficients demonstrated that spherical aberration (z4 0) significantly correlated with nuclear cataract only (age-adjusted coef = 0.37 and p = 0.012). conclusion: this report is the first to describe the distribution of higher-order aberrations in an iranian population. higher-order aberrations in this study were on average higher that those reported in previous studies. © 2015 iranian society of ophthalmology.