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Determining Stress Distribution in a Longitudinal Keratoconus Cohort.
Magali M S Vandevenne1,2, Cynthia J Roberts3,4, Mathew Francis5
1University Eye Clinic Maastricht, Maastricht University Medical Center+, Maastricht, the Netherlands.
Cornea
|December 11, 2025
Summary
Keratoconus progression can be predicted by analyzing corneal stress patterns. The difference in corneal stress (CCSdiff) at baseline helps forecast changes in corneal curvature over time.
Area of Science:
- Ophthalmology
- Biomechanical Engineering
- Corneal Imaging Analysis
Background:
- Keratoconus is a progressive corneal ectasia characterized by thinning and steepening.
- Accurate prediction of keratoconus progression is crucial for timely intervention and management.
- Current methods for predicting progression have limitations in capturing early biomechanical changes.
Purpose of the Study:
- To evaluate if stress distribution patterns in keratoconus eyes can predict future biomechanical progression.
- To utilize longitudinal data to assess the predictive capability of corneal stress parameters.
Main Methods:
- Calculated corneal contribution to stress (CCS) using a modified Hoop stress formula (CCS = r/2t).
- Analyzed CCS from Pentacam curvature and thickness maps, focusing on the difference between minimum and maximum CCS zones (CCSdiff).
- Employed a linear mixed model to assess the predictive ability of CCSdiff on longitudinal changes in corneal curvature (Cspot).
Main Results:
- Included 114 keratoconus eyes and 31 healthy control eyes.
- Baseline CCSdiff in keratoconus eyes was significantly correlated with maximum zonal tangential curvature (Cspot) (r = 0.83, P < 0.001).
- Baseline CCSdiff was a significant predictor of Cspot progression over time (P < 0.001).
Conclusions:
- The difference in corneal stress distribution (CCSdiff) is dynamic and changes over time.
- Baseline CCSdiff values effectively predict future biomechanical progression in keratoconus patients.
- This stress-based metric offers a novel approach for monitoring keratoconus progression.
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