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Associations between refractive error components and higher-order aberrations in simple myopia and compound myopic
Sahar Mohaghegh1, Shahram Bamdad2, Haleh Kangari1
1Department of Optometry, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Frontiers in Ophthalmology
|April 4, 2025
Summary
Higher-order aberrations (HOAs) correlate with myopia and astigmatism. Wavefront error increases with myopia and astigmatism, with specific aberrations linked to astigmatism direction in adult myopic eyes.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Refractive errors, including myopia and astigmatism, are common visual conditions.
- Higher-order aberrations (HOAs) contribute to visual quality beyond basic refractive error correction.
- Understanding the relationship between refractive components and HOAs is crucial for advanced vision correction strategies.
Purpose of the Study:
- To investigate the associations between refractive error components (myopia and astigmatism) and higher-order aberrations (HOAs) in adult myopic subjects.
- To analyze Zernike components of HOAs and their correlation with refractive error parameters.
- To compare HOA profiles between simple myopia and compound myopic astigmatism subgroups.
Main Methods:
- Cross-sectional study of 1370 adult myopic right eyes (aged 18-40).
- Measurement of subjective cycloplegic refractions and distance aberrometry using a Shack-Hartmann device.
- Analysis of Zernike components (coma, trefoil, spherical aberration) and total root-mean-square (RMS) wave-front error for a 6 mm pupil, with correlation analysis and subgroup comparisons.
Main Results:
- Total RMS wave-front error showed a significant correlation with spherical equivalent myopia (r = -0.1, P<0.05) and J45 astigmatism (r = 0.1, P<0.001).
- Specific HOAs, including vertical coma (Z3-1), oblique trefoil (Z33), and vertical trefoil (Z3-3), demonstrated correlations with refractive components.
- Total RMS wave-front error was significantly larger in the compound myopic astigmatism subgroup compared to the simple myopia subgroup (|0.37| ± 0.18 µm vs |0.34| ± 0.16 µm, P <0.001).
Conclusions:
- Total RMS wave-front error increases with the severity of myopia and astigmatism.
- While increasing myopia power did not show a systematic correlation with individual HOA components, a weak correlation was observed between astigmatism direction and third-order aberrations.
- These findings highlight the complex interplay between refractive error components and HOAs, influencing overall wavefront error in myopic eyes.
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