Defining the Operating Parameters for a Rebound-esthesiometer

Study Overview
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Brief Summary
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The purpose of this study is to define the operating parameters for a new method to measure corneal sensitivity.

Detailed Description
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Corneal sensitivity is the most important protective mechanism of the eye. Thus, measuring it at any given time gives important indicators of corneal physiology, especially in the diagnostics of corneal and systemic diseases (e.g. diabetes, herpes simplex and keratitis) and recovery from ocular surgery. Current commercial measurement methods are outdated, non-quantitative and uncomfortable to use, hence left unused. This results in suboptimal, even poor, diagnosis and treatment for patients. In this study the operating parameters for a state-of-the-art esthesiometer are defined. The operating principle is based on existing rebound technology which is already approved for IOP measurement.

Official Title
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Rebound Esthesiometer Phase 2 Protocol

Conditions
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Corneal Sensation Reduced, Corneal Dystrophy, Corneal Degeneration, Corneal Transplant Failure, Herpetic Keratitis

Intervention / Treatment
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* Device: Esthesiometer measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age >= 18 Informed consent signed Exclusion Criteria: Signs of infectious or inflammatory disease of anterior eye at the time of presentation. During last two weeks, any of the following events or conditions occurred or was present: inflammatory or infectious ocular condition, surgical or other intervention or therapy, other abnormal ocular event. Unable to give informed consent. Directly or indirectly indicated vunerability.

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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Test subjects<br>Test subjects according to the inclusion / exclusion criterias. | Device: Esthesiometer measurement<br>* Measuring the corneal sensitivity using rebound technology.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rebound esthesiometer operating threshold | Define the corneal touch sensitivity threshold using the rebound esthesiometer by varying the measurement probe impact at the moment of touch of corneal surface. The impact is varied by changing the speed (m/s) of the measurement probe and the subjective sensation of the test subject is recorded. The mass (mg) of the measurement probe is known and the impact energy is calculated. | 2020-2021 | 
| Rebound esthesiometer operating parameters | Measure the correlation of corneal touch sensitivity between rebound esthesiometer and the reference instrument Cochet-Bonnet monofilament esthesiometer. With the rebound esthesiometer the impact is varied by changing the speed (m/s) of the measurement probe. The probe mass (mg) and speed (m/s) equals to the touch impact impulse which causes the touch sensation. The subjective sensation of the test subject is recorded. | 2020-2021 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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esthesiometry, corneal sensitivity