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Comparison of keratometric values and corneal eccentricity
Pavel Benes1, Svatopluk Synek, Sylvie Petrová
1Faculty of Medicine, Department of Non-medical Branch, Brno, Czech Republic. optika.rubin@seznam.cz
Collegium Antropologicum
|July 11, 2013
Summary
This study compared corneal eccentricity in myopia, hyperopia, and emmetropia, finding similar values across refractive errors. These keratometric and topographic measurements are crucial for selecting appropriate contact lenses for vision correction.
Area of Science:
- Ophthalmology
- Optometry
- Corneal Topography
Background:
- Refractive errors like myopia and hyperopia affect millions globally.
- Accurate measurement of corneal parameters is essential for vision correction.
- Corneal eccentricity influences optical outcomes and contact lens fitting.
Purpose of the Study:
- To compare keratometric values and corneal eccentricity across different refractive error groups.
- To investigate the topographic differences in the cornea related to refractive error.
- To highlight the importance of these measurements for contact lens selection.
Main Methods:
- A cohort of 300 subjects (600 eyes) was divided into myopia, hyperopia, and emmetropia groups.
- Autorefractokeratometry with a Placido disc was used to measure corneal topography.
- Steepest and flattest meridians were recorded to calculate corneal eccentricity.
Main Results:
- Corneal eccentricity values were similar across all groups: 0.37 for myopia, 0.37 for hyperopia, and 0.36 for emmetropia.
- Keratometric measurements showed variations in steepest and flattest meridians between groups.
- Topographical analysis provided insights into corneal shape differences.
Conclusions:
- Corneal eccentricity shows minimal variation across common refractive errors.
- Keratometry and corneal topography are fundamental for assessing the anterior corneal surface.
- Precise corneal measurements are vital for successful contact lens fitting and refractive error management.
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