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Updated: Jun 25, 2026
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Development of an In Vitro Ocular Platform to Test Contact Lenses
Published on: April 6, 2016
Tear ferning in contact lens wearers
Katharine S E Evans1, Rachel V North, Christine Purslow
1Contact Lens and Anterior Eye Research (CLAER) Unit, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff, UK.
Summary
Tear ferning (TF) shows differences between contact lens (CL) and non-contact lens (NCL) wearers, even in asymptomatic individuals. However, TF has limited ability to predict ocular comfort in either group.
Area of Science:
- Ophthalmology
- Optometry
- Tear Film Research
Background:
- Tear ferning (TF) is a diagnostic test for dry eye.
- Its utility in contact lens (CL) wearers and correlation with ocular comfort require further investigation.
Purpose of the Study:
- To examine the relationship between tear ferning (TF), ocular comfort, and tear film stability.
- To compare these parameters between contact lens (CL) and non-contact lens (NCL) wearers.
Main Methods:
- Assessed non-invasive tear break-up time (NIBUT) and fluorescein tear break-up time (FBUT).
- Administered the Ocular Comfort Index (OCI) questionnaire.
- Collected and analyzed tear samples for TF patterns using Rolando's grading scale.
Main Results:
- CL wearers exhibited significantly higher TF grades and ocular discomfort (OCI scores) than NCL wearers.
- No significant differences in tear film stability were found between the groups.
- TF patterns differed significantly between CL and NCL wearers, irrespective of symptoms.
Conclusions:
- Higher TF grades in CL wearers suggest altered tear film composition (salt/macromolecule ratio).
- Similar TF patterns in symptomatic CL and NCL wearers may indicate shared etiology (hyperosmolarity).
- TF demonstrates limited sensitivity and specificity for predicting ocular surface comfort in both CL and NCL wearers.
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