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Updated: Jun 1, 2026
08:28
Development of an In Vitro Ocular Platform to Test Contact Lenses
Published on: April 6, 2016
Parameter and environmental influences on rigid contact lens wettability
J W Huff1, D J Egan, M J Katich
1School of Optometry, University of Missouri-St. Louis.
American Journal of Optometry and Physiological Optics
|September 1, 1988
Summary
Contact angle measurements for rigid contact lenses are largely unaffected by lens parameters like surface radius and environmental factors such as humidity. This study found lens wettability is consistent across various conditions, simplifying in vitro testing.
Area of Science:
- Ophthalmology
- Materials Science
- Biomedical Engineering
Background:
- Contact angle measurements are crucial for assessing the wettability of contact lens materials.
- Understanding factors influencing these measurements is essential for accurate in vitro evaluation of lens performance and patient comfort.
Purpose of the Study:
- To investigate the impact of specific lens parameters and environmental conditions on contact angle measurements of rigid contact lenses.
- To determine the reliability of goniometric measurements under varying in vitro conditions.
Main Methods:
- Sessile drop contact angle measurements of saline on four rigid contact lens materials (PMMA, silicone/acrylate) using a Ramé-Hart goniometer.
- Systematic variation of front surface radius, drop size, time post-placement, humidity, and hydration state.
Main Results:
- Contact angles were largely uninfluenced by front surface radii within tested ranges for most materials.
- Drop size, humidity (31-76%), and hydration state did not significantly affect contact angles.
- Time after drop placement (1-6 min) and surface scratches also showed no significant impact on wettability.
Conclusions:
- Goniometric measurements of contact lens wettability are robust and minimally affected by common lens parameters and environmental variations.
- The findings support the reliability of in vitro contact angle testing for rigid contact lenses, simplifying material assessment.
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