Higher order aberrations in a normal adult population

Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran
Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran
Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
Center for Health Related Social and Behavioral Sciences Research, Shahroud University of Medical Sciences, Shahroud, Iran
Department of Community Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran



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.


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.


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, Z31, Z5−1, Z51), Total RMS trefoil (Z3−3, Z33, Z5−3, Z53), and spherical aberration (Z40) 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 (Z40) significantly correlated with nuclear cataract only (age-adjusted Coef = 0.37 and p = 0.012).


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.


Zernike coefficients, Higher order aberrations, Population based study, Adult.

How to Cite

Hassan Hashemi, Mehdi Khabazkhoob, Ebrahim Jafarzadehpur, Abbasali Yekta, Mohammad Hassan Emamian, Mohammad Shariati, Akbar Fotouhi,
Higher order aberrations in a normal adult population,
Journal of Current Ophthalmology,
Volume 27, Issues 3–4,
Pages 115-124,
ISSN 2452-2325,
Keywords: Zernike coefficients; Higher order aberrations; Population based study; Adult