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Published on: September 16, 2025
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Objective analysis of contact lens fit
Lurdes Belda-Salmerón1, Tom Drew2, Lee Hall3
1Optics Department, Faculty of Physics, University of Valencia, Spain.
Summary
Objective contact lens fit analysis provides accurate and repeatable assessments, proving valuable for research and clinical practice. This method enhances the understanding and optimization of soft contact lens fitting for better patient outcomes.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Optometry
Background:
- Accurate contact lens fitting is crucial for ocular health and visual acuity.
- Subjective assessment of contact lens fit can be influenced by observer variability.
- Objective methods offer potential for more precise and reproducible measurements.
Purpose of the Study:
- To evaluate the validity and repeatability of objective contact lens fit analysis compared to subjective methods.
- To determine the accuracy of objective measurements for key lens fit parameters.
Main Methods:
- Thirty-five subjects wore two soft contact lens designs.
- Four fit variables (centration, horizontal lag, blink movement, recovery speed) were assessed by four observers and via objective image analysis.
- Measurements were repeated after one week to assess repeatability.
Main Results:
- Objective and subjective assessments showed significant variations in centration, blink movement, lag, and recovery speed (p<0.001).
- Horizontal centration was similar between methods (p>0.05).
- Objective analysis demonstrated good repeatability for vertical centration and movement-on-blink, though subjective assessment showed better repeatability for blink movement and horizontal lag within their respective ranges.
Conclusions:
- Objective image analysis provides an accurate, reliable, and repeatable method for assessing soft contact lens fit.
- This objective approach is a valuable tool for contact lens research and optimizing clinical fitting practices.
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