Higher order aberrations in a normal adult population

Area of Science:

• Ophthalmology
• Optometry
• Vision Science

Background:

• Higher-order aberrations (HOA) significantly impact visual quality.
• Understanding HOA distribution is crucial for diagnosing and managing visual impairments.
• Previous studies on HOA distribution have primarily focused on Western populations.

Purpose of the Study:

• To investigate the prevalence and distribution of Zernike coefficients and higher-order aberrations in a normal Iranian population.
• To examine the relationship between HOA and demographic factors (age, gender), biometric components, and refractive error (spherical equivalent).

Main Methods:

• A subsample of 904 eyes from 577 participants (aged 40-64) in the Shahroud cohort study were analyzed.
• Aberrations were measured using a Zywave aberrometer before cycloplegic refraction with a minimum pupil diameter of 5 mm.
• Statistical analysis explored correlations between HOA and age, gender, axial length, refractive error, and nuclear opacity.

Main Results:

• Mean higher-order Zernike RMS was 0.306 μm, higher than previously reported.
• HOA significantly correlated with older age and shorter axial length.
• Increased nuclear opacity was strongly associated with higher HOA (p < 0.001), and spherical aberration correlated with nuclear cataract (p = 0.012).

Conclusions:

• This is the first study to report HOA distribution in an Iranian population.
• The findings suggest that HOA in this population are generally higher than in other reported groups.
• Age, axial length, and nuclear opacity are significant factors influencing HOA.