Correlation of Different Signs for Assessment of Dry Eye Syndrome

Study Overview
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Brief Summary
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Dry eye syndrome (DES) is a highly prevalent ocular condition inducing an inflammatory response of the ocular surface. Common symptoms include ocular discomfort, visual impairment and instability of the tear film with potential damage to the ocular surface. The rationale of the present study is to compare signs as assessed with new methods such as measurement of tear film thickness, tear film osmolarity and scattering of the tear film with well established methods for assessment of the severity of DES (Break up time, staining of the cornea with fluorescein). Additionally, impression cytology and determination of tear cytokines/chemokines will be performed to obtain information about inflammatory processes on the ocular surface.

Official Title
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Correlation of Different Signs for Assessment of Dry Eye Syndrome

Conditions
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Dry Eye Syndrome

Intervention / Treatment
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* Other: Ocular scattering of the tear film
* Other: Optical Coherence Tomography (OCT)
* Other: Measurement of tear film osmolarity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women aged over 18 years History of dry eye syndrome for at least 3 months At least 2 symptoms of dry eye syndrome (foreign body sensation, burning, photophobia, blurred vision, pain, itching) and/or tear break up time < 10 seconds Normal ophthalmic findings except dry eye syndrome Exclusion Criteria: Participation in a clinical trial in the 3 weeks preceding the study Symptoms of a clinically relevant illness in the 3 weeks before the first study day Presence or history of a severe medical condition that will interfere with the study aim as judged by the clinical investigator Wearing of contact lenses Intake of dietary supplements in the 3 months preceding the study Glaucoma Treatment with corticosteroids in the 4 weeks preceding the study Topical treatment with any ophthalmic drug in the 4 weeks preceding the study except topical lubricants Ocular infection or clinically significant inflammation Ocular surgery in the 3 months preceding the study Sjögren's syndrome Stevens-Johnson syndrome Pregnancy, planned pregnancy or lactating

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: 50 patients with dry eye syndrome<br> | Other: Ocular scattering of the tear film<br> <br> * Other names: OQAS, Visometrics, Spain;Other: Optical Coherence Tomography (OCT)<br>* Tear film thickness as measured with OCT<br>Other: Measurement of tear film osmolarity<br> <br> * Other names: TearLab®, OcuSens Inc, San Diego, USA;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Break up time | break up time of the tear film measured in seconds | once on the study day | 
| Tear film thickness as measured with optical coherence tomography (OCT) | tear film thickness measured in micrometers | once on the study day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Acuity | Total number of letters read using ETDRS Charts | once on the study day | 
| Tear film osmolarity | Tear film osmolarity measured in mosmol/l | once on the study day | 
| OSI (Objective Scattering Index) | The objective scattering index will be measured using the OQAS system (Visiometrics, Spain) | once on the study day | 
| Staining of the cornea with fluorescein | The cornea will be divided into 5 regions (central, inferior, nasal, temporal, inferior) and each region will be graded from 0-4 in 0.5 steps as described in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) study. | once on the study day | 
| Impression cytology | After topical anesthesia of the eye, filter material is placed on the conjunctiva to obtain cytological samples, which will be prepared and evaluated. | once on the study day | 
| Tear cytokines/chemokines | Samples of 40 µl tears will be taken with a glass capillary and stored in vials. The concentrations of several cytokines and chemokines will be evaluated. | once on the study day | 
| Subjective symptoms of dry eye syndrome | a questionaire will be used | once on the study day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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break up time, tear film thickness, tear film osmolarity, objective scattering index, impression cytology, tear cytokines/chemokines, visual acuity, fluorescein staining