Validation of a Newly Developed Liquid Jet Aesthesiometer

Study Overview
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Brief Summary
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A new liquid jet aesthesiometer prototype was developed with the aim to measure ocular surface sensitivity by employing a liquid jet. This study aims to validate this new prototype by means of correlating its measurement with a previously validated air jet aesthesiometer, the non-contact aesthesiometer (NCCA; by Murphy et al. 1996) and by exploring the repeatability of ocular surface sensitivity measurement.

Detailed Description
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Currently, no aesthesiometer is available that delivers reliable and repeatable measurement of ocular surface sensitivity in a routine clinical setup. The only commercially available Cochet- Bonnet aesthesiometer uses a tactile-mechanical stimulus (the tip of a nylon thread), which can cause a microerosion when applied to the corneal surface. Additional disadvantages represent poor stimulus reproducibility, a limited stimulus bandwidth and the influence of humidity and age on the bending capibility of the nylon thread. For research purposes prototypes of non-contact air aesthesiometers (eg by Murphy et al. and Belmonte et al) are being used. This study aims to correlate ocular surface sensitivity measurements of a newly developed prototype, the liquid jet aesthesiometer, with the non-contact air jet aesthesiometer by Murphy et al. 1996 and to explore its repeatability of measurement. In this repeated measures design 60 subjects participate in corneal sensitivity measurements during two appointments with each described aesthesiometer.

Official Title
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Validation of a Newly Developed Liquid Jet Aesthesiometer

Conditions
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Ocular Surface Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ocular surface index score < 13.0 Exclusion Criteria: systemic disease such as diabetes, diseases, injuries and operations in the anterior segment of the eye systemic medication and / or eyedrops / ointments that may have an influence of the tearfilm. contact lens wear less than 48 hours before commencement of study measurements.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| corneal sensitivity measurement<br>Air jet aesthesiometry and liquid jet aesthesiometry: All patients will receive the same intervention of corneal sensitivity measurement with air jet aesthesiometry and liquid jet aesthesiometry. Thresholds represent the intensity of air / liquid jet that can just be perceived by the patients. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation with air jet aesthesiometry | correlation between corneal sensitivity measurements between liquid jet and air jet aesthesiometry | two measurements / repeated measures within one month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| repeatability of corneal sensitivity measurement with new prototype | repeatability of corneal sensitivity measurement with liquid jet aesthesiometry | two measurements / repeated measures within one month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ocular surface sensitivity