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Optimal modeling of corneal surfaces with Zernike polynomials
D R Iskander1, M J Collins, B Davis
1Centre for Eye Research, Queensland University of Technology, Victoria Park Rd, Kelvin Grove Q4059, Australia. d.iskander@qut.edu.au
IEEE Transactions on Bio-Medical Engineering
|March 10, 2001
Summary
The bootstrap method offers a superior approach for selecting Zernike polynomial orders in corneal modeling. This technique objectively determines the optimal number of Zernike terms for accurate corneal elevation data analysis.
Area of Science:
- Ophthalmology
- Optical Engineering
- Biomedical Optics
Background:
- Zernike polynomials are crucial for analyzing optical wavefronts and modeling corneal surfaces.
- Accurate corneal modeling requires appropriate selection of Zernike polynomial expansion order based on measured data.
Purpose of the Study:
- To compare classical model order selection techniques with a bootstrap approach for fitting Zernike polynomials to corneal data.
- To demonstrate the superiority of the bootstrap method for objective selection of the optimal number of Zernike terms.
Main Methods:
- Simulations were conducted to compare the performance of classical model order selection techniques.
- A bootstrap-based approach was developed and validated for fitting Zernike polynomials to corneal elevation data.
- The method was applied to both normal and distorted corneas to assess its efficacy.
Main Results:
- The bootstrap method significantly outperformed classical techniques in simulations for Zernike polynomial order selection.
- The bootstrap technique proved to be the most appropriate method for fitting Zernike polynomials to corneal elevation data.
- Optimal model order selection was found to be dependent on the corneal diameter.
Conclusions:
- The bootstrap method provides an objective and effective way to select the optimal number of Zernike terms for corneal surface analysis.
- This approach enhances the accuracy of corneal modeling, particularly for eyes with significant distortions.
- The findings support the use of the bootstrap technique in clinical and research settings for precise ophthalmic optical analysis.
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