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Updated: Aug 9, 2026
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Development of an In Vitro Ocular Platform to Test Contact Lenses
Published on: April 6, 2016
Osmotic adaptation to rigid contact lenses
Archives D'Ophtalmologie
|January 1, 1977
Summary
Rigid contact lens wear initially causes tear osmotic pressure to decrease. Over the first week, tear osmotic pressure increases, establishing a new, more concentrated baseline for adapted rigid contact lens wearers.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Physiological Optics
Background:
- Rigid contact lenses are used to correct vision.
- Understanding the physiological response to contact lens wear is crucial for patient comfort and eye health.
Purpose of the Study:
- To monitor tear osmotic pressure changes during adaptation to rigid contact lenses.
- To investigate the physiological shifts in tear osmolarity in response to rigid contact lens wear.
Main Methods:
- Utilized a precision thermocouple hygrometer for tear osmolarity measurement.
- Analyzed tear samples as small as 5 microliters from 6 subjects.
- Monitored tear osmotic pressure throughout the adaptation period to rigid contact lenses.
Main Results:
- Subjects initially exhibited hypotonic shifts in tear osmotic pressure upon lens insertion.
- This osmotic imbalance was corrected by the end of the first wearing week.
- A new, relatively hypertonic tear osmotic pressure baseline was commonly established after adaptation.
Conclusions:
- Rigid contact lens wear induces significant, yet temporary, changes in tear osmolarity.
- The ocular surface adapts to rigid contact lenses, leading to a sustained hypertonic tear state.
- These findings provide insights into the physiological adaptation mechanisms of the ocular surface to contact lens wear.
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