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Higher order aberrations in normal eyes measured with three different aberrometers
Ahmet Z Burakgazi1, Bernard Tinio, Alejandro Bababyan
1Department of Ophthalmology, Mount Sinai School of Medicine, New York, NY 10029, USA. drburakgazi@yahoo.com
Journal of Refractive Surgery (Thorofare, N.J. : 1995)
|November 28, 2006
Summary
Three aberrometers showed repeatable higher order aberration measurements, but significant differences existed between optical path difference (OPD) scanning and Hartmann-Shack methods, indicating all are reliable yet distinct.
Area of Science:
- Ophthalmology
- Optometry
- Optical Engineering
Background:
- Accurate measurement of higher order aberrations is crucial for understanding visual quality.
- Different aberrometry techniques may yield varying results.
- Evaluating the repeatability and comparability of aberrometers is essential for clinical application.
Purpose of the Study:
- To assess the repeatability of higher order aberration (HOA) measurements using three distinct aberrometers.
- To compare HOA measurements between optical path difference (OPD) scanning and Hartmann-Shack aberrometry methods.
- To determine the reliability and comparability of NIDEK OPD-Scan, Bausch & Lomb Zywave, and VISX CustomVue wavefront analyzers.
Main Methods:
- Wavefront aberration data were collected from 19 subjects using NIDEK OPD-Scan, Bausch & Lomb Zywave, and VISX CustomVue.
- Repeatability was assessed by calculating differences between consecutive measurements and their mean.
- Statistical analysis included mean difference, standard deviation, and 95% confidence intervals (repeatability coefficient).
Main Results:
- All three aberrometers demonstrated low repeatability errors, indicating reliable repeated measurements.
- Statistically significant differences were observed between optical path difference (OPD) scanning and Hartmann-Shack aberrometry methods.
- Significant differences in several higher order aberration parameters were found when comparing the three instruments.
Conclusions:
- The evaluated aberrometers provide repeatable measurements of higher order aberrations.
- Despite good repeatability, statistically significant differences exist in HOA measurements between the devices and techniques.
- No single instrument demonstrated superiority; all three were deemed reliable for repeated measurements.
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