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Lower Tear Meniscus Height Measurements Using Keratography and Swept-Source Optical Coherence Tomography and Effect
Andrew Kc Lam1, Shirley Ky Tai1, Jacky Kt Chan1
1Laboratory of Experimental Optometry, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China.
Current Eye Research
|June 12, 2019
Summary
Keratography and swept-source OCT offer similar tear meniscus height (TMH) measurements. Fluorescein instillation can overestimate TMH, but its application location and subjective sensation do not impact results.
Area of Science:
- Ophthalmology
- Biomedical Optics
- Corneal Imaging
Background:
- Accurate measurement of inferior tear meniscus height (TMH) is crucial for diagnosing dry eye disease.
- Comparing different imaging modalities and their measurement conditions is essential for clinical standardization.
Purpose of the Study:
- To compare inferior tear meniscus height (TMH) measurements between keratography and swept-source optical coherence tomography (OCT).
- To investigate the effect of fluorescein instillation location and subjective sensation on TMH measurements.
Main Methods:
- Forty-one healthy adult eyes underwent TMH measurement using keratography and swept-source OCT.
- Measurements were taken at baseline and after fluorescein strip application to either bulbar or palpebral conjunctiva.
- Two-way ANOVA analyzed differences between devices and conditions; subjective sensation was recorded on a 4-point scale.
Main Results:
- No significant difference was found in TMH measurements between keratography and swept-source OCT (p = .451).
- Fluorescein instillation significantly increased TMH (p < .001), from 0.25 mm to 0.28 mm.
- Subjective ocular sensation was similar for both fluorescein application sites and not significantly associated with TMH.
Conclusions:
- Keratography and swept-source OCT provide comparable TMH measurements.
- Fluorescein sodium application via a moistened strip can lead to an overestimation of TMH by approximately 0.03 mm.
- The location of fluorescein strip application (bulbar vs. palpebral conjunctiva) does not significantly affect subjective sensation or TMH measurements.
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