Retrospective NIS to Evaluate the Patient Benefit of TES

Study Overview
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Brief Summary
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In this retrospective non-interventional study (NIS), the subjective and objective benefit of patients with retinitis pigmentosa (and other dystrophies like Usher, Choroideremia or cone-rod dystrophy), who have been prescribed the therapy of transcorneal electrostimulation (TcES) with the OkuStim System, is assessed.

Detailed Description
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The medical device OkuStim received the CE mark (a symbol of free marketability in the European Economic Area) in 2011 and is commercially available for patients in Europe since 2014. Since then, patients with retinitis pigmentosa and other dystrophies have regularly applied the therapy of transcorneal electrostimulation (TcES) with OkuStim. So far, the benefits of the therapy and the experiences of the patients with regular, multi-year use have not been systematically recorded. In this retrospective non-interventional study (NIS) with patients which have been using TcES since >1 year, data present for visual field, best-corrected visual acuity (BCVA) and central foveal thickness (as assessed via OCT) is collected. In addition, reasons for discontinuation of therapy and patient satisfaction with TcES are assessed via a questionnaire. Side-effects are also recorded, if present in the patient files.

Official Title
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Retrospective Non-Interventional Study to Evaluate the Patient Benefit of Transcorneal Electrostimulation (TES)

Conditions
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Retinitis Pigmentosa

Intervention / Treatment
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* Device: Transcorneal Electrostimulation via OkuStim System


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Use of TcES for >1year Willing and able to consent Exclusion Criteria: Not willing and able to consent
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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: Transcorneal Electrostimulation via OkuStim System|Transcorneal electrostimulation, usually applied once per week for 30 min (home-use).|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual field | Assessment of changes compared to baseline (before TcES was started) | Baseline and then all data present in patient files after begin of therapy. Depending on how long the patient already uses OkuStim, the time frame varies between 1 year and several years after commencement of therapy. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best-corrected visual acuity | Assessment of changes compared to baseline (before TcES was started) | Baseline and then all data present in patient files after begin of therapy. Depending on how long the patient already uses OkuStim, the time frame varies between 1 year and several years after commencement of therapy. | 
| Central foveal thickness | Assessment of changes compared to baseline (before TcES was started) | Baseline and then all data present in patient files after begin of therapy. Depending on how long the patient already uses OkuStim, the time frame varies between 1 year and several years after commencement of therapy. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transcorneal Electrostimulation, TcES, TES, Inherited retinal dystrophy, Retinopathia pigmentosa, Retinitis pigmentosa