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Updated: Aug 15, 2026
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Inducement and Evaluation of a Murine Model of Experimental Myopia
Published on: January 22, 2019
Control of the myopic shift in modified Badal optometer
1Karol Marcinkowski University of Medical Sciences, Department of Optometry, Poznań, Poland.
Summary
The Badal optometer often overestimates myopia. Controlling retinal image size during refractive error measurement significantly improves accuracy, aligning perceived endpoints with actual refractive error when image size diminishes with target approach.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Badal optometers are standard tools for refractive error measurement.
- These devices can inaccurately measure myopia, overestimating its severity.
Purpose of the Study:
- To investigate the impact of retinal image size on Badal optometer measurements.
- To determine how controlling image size affects refractive error endpoint perception.
Main Methods:
- Modified a Badal optometer with a camera zoom lens to control retinal image size.
- Assessed subjective endpoints of refractive error measurement under varying image sizes.
Main Results:
- Retinal image size is a critical factor influencing the subjective endpoint.
- Diminishing retinal image size as the target approaches improved measurement accuracy.
Conclusions:
- Adjusting retinal image size is key to enhancing Badal optometer precision.
- The findings suggest a method to improve the accuracy of myopia assessment.
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