Metabolites of Tear Fluid

Study Overview
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Brief Summary
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The pilot trial evaluates the use of modified Schirmer strips and is designed to evaluate inter-individual range of metabolites in tear film.

Detailed Description
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The variability of tear film metabolites should be investigated in a sample of ophthalmologists in preparation for a pilot study in patients eye diseases. The easy accessibility of the tear fluid and the lack of invasiveness of the study make it promising and sensible to determine the concentration of various tear film metabolites. Because attention has so far focused primarily on the quantitative and qualitative analysis of tear film proteins, many metabolites have so far only been shown to be contained in tears. However, before the suitability of the measured values as a predictive parameter of the ocular surface for pathologies can be examined and assessed, it is necessary to determine the scattering variables in a sample of healthy volunteers. Thus, reference areas are to be defined for later investigations in order to enable reliable case number planning thereafter. Repeated determinations at different times and on different days make it possible in particular to detect a time-dependent relationship in view of the dynamic variability of the tear film. The functional significance of certain metabolites can not yet be assessed in the establishment phase. However, the data may provide important information for the interpretation of a later, planned feasibility study with diseased patients or the influence of applied eye drops.

Official Title
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Metabolites of Tear Fluid - Evaluation in a Clinical Pilot Study

Conditions
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Healthy Subjects

Intervention / Treatment
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* Diagnostic Test: Tear Sampling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy subjects at age > 18 years Exclusion Criteria: in the case of subjects with a mental disability or legal guardianship, due to possible conflicts for the caregivers, a data evaluation and recording should in principle be dispensed with. subjects who have had any eye drops within the last 4 weeks, e.g. lubricants were used subjects undergoing clinical examination for symptoms of wetting disorder or morphological changes related to eye disease

Ages Eligible for Study
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Minimum Age: 18 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

| Intervention/Treatment |
| --- |
|Diagnostic Test: Tear Sampling|comprehensive eye exam, Schirmer test, break-up time, tear sampling|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| concentration of analytes (lipids, proteins/amino acids) | level of analytes (ng/ml) | 3 days per patient | 
| number of detecatable analytes | number of analytes (lipds, proteins/amino acids) | 3 days per patient | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Tear, Metabolite