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Keratoconus: A Probe Into the Refractive Symmetry.

Sankhajyoti Saha1, Moubani Dutta1, Soumendra Nath Bandyopadhyay1

  • 1Department of Health Science, NSHM Knowledge Campus, Kolkata, West Bengal, India.

Journal of Ophthalmology
|October 24, 2025
PubMed
Summary

Mirror symmetry is a significant predictor of keratoconus severity, correlating positively with corneal diopter and negatively with thickness and asphericity. This finding offers insights into keratoconus progression and management.

Keywords:
asphericity coefficientcorneal dioptercorneal thicknesskeratoconusmirror symmetry

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Area of Science:

  • Ophthalmology
  • Biomedical Engineering
  • Corneal Research

Background:

  • Keratoconus is a progressive corneal ectasia causing vision impairment.
  • It involves thinning and outward protrusion of the cornea into a cone shape.
  • Understanding keratoconus progression is crucial for effective management.

Purpose of the Study:

  • To evaluate the reliability of mirror symmetry in assessing keratoconus severity.
  • To determine the impact of mirror octants on keratoconus progression.
  • To quantify the relationship between enantiomorphism and keratoconus dimensions.

Main Methods:

  • Bilateral keratoconus and astigmatism patients were included.
  • Mirror symmetry was quantified using refractive cylindrical notations.
  • Pentacam imaging assessed corneal thickness, thinning, and asphericity.
  • Statistical analysis included Multiple R, ANOVA, and scatter plots using SPSS 29.0.

Main Results:

  • Mirror symmetry was a statistically significant predictor (p < 0.05) in the regression model.
  • Average corneal diopter showed a positive correlation with mirror symmetry.
  • Corneal thickness and asphericity exhibited a negative correlation with mirror symmetry.

Conclusions:

  • Mirror symmetry's predictive power is influenced by corneal contour analysis.
  • The current model explains 35.6% of variability, suggesting room for improvement.
  • Incorporating nonlinear predictors could enhance the model's accuracy for keratoconus assessment.