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Corneal spherical aberration in Saudi population.
Tarfah M Al-Sayyari1, Samah M Fawzy2, Ahmed A Al-Saleh3
1Optometrist, Riyadh, Saudi Arabia.
Summary
Corneal spherical aberration (CSA) increases with age in the Saudi population, with higher-order aberrations comprising a significant portion of total corneal aberrations. This finding highlights age-related changes in ocular optics.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Corneal aberrations, particularly higher-order aberrations (HOA), can impact visual quality.
- Understanding age-related changes in corneal optics is crucial for ophthalmic practice and refractive surgery outcomes.
Purpose of the Study:
- To determine the mean corneal spherical aberration (CSA) in the Saudi population.
- To investigate the relationship between age and CSA in this demographic.
Main Methods:
- A cross-sectional study involving 185 Saudi subjects (300 eyes) aged 15-85 years.
- Corneal spherical aberration (Z4 (0)) was measured using a Pentacam HR device at a 6-mm optical zone.
- Subjects were categorized into three age groups for comparative analysis.
Main Results:
- The mean fourth-order CSA (Z4 (0)) was 0.252 ± 0.1154 μm.
- A significant positive correlation was observed between CSA and age (r = 0.3429, P < 0.0001).
- Older age groups (50-85 years) exhibited higher CSA compared to younger groups, with a significant increase in CSA-RMS (P < 0.0001).
- Pupil diameter showed a negative correlation with increasing age (P = 0.0012).
Conclusions:
- Corneal spherical aberration varies within the Saudi population and significantly increases with age.
- Fourth-order spherical aberration is a major component of higher-order aberrations in the cornea.
- These age-related changes in corneal optics are comparable to findings in other populations.
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