Transcorneal Electrostimulation for Therapy of Retinitis Pigmentosa
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ClinicalTrials.gov Identifier: NCT01837901 |
Recruitment Status :
Completed
First Posted : April 23, 2013
Results First Posted : March 18, 2021
Last Update Posted : March 18, 2021
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Condition or disease | Intervention/treatment | Phase |
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Retinitis Pigmentosa | Device: Transcorneal electrostimulation | Not Applicable |
The study was performed at the Centre for Ophthalmology, University of Tübingen, Germany. The protocol was approved by the local ethics committee. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008. Informed consent was obtained from all patients for being included in the study. The study was conducted according to the standards of GCP, the European Union Directive for Medical Devices, and the German Medical Product Law.
Patients were seen at 14 visits over a period of 78 weeks: one baseline visit (screening), followed by 12 visits (in week 1-4 weekly, then in weeks 10, 16, 22, 28, 34, 40, 46 and 52; dates varied a maximum of ± 1 week) including application of TcES for 52 weeks and one follow-up visit (in week 78, dates varied a maximum of ± 1 week).
After inclusion patients were randomly assigned to TcES with 0 mA (sham), 150% or 200% of their individual electrical phosphene threshold (EPT) current at 20 Hz.
Patients and technicians who performed kinetic perimetry, as well as full-field electrophysiology (ERG), multifocal ERG (mfERG) and dark adaptation, were blinded to the treatment group for the entire study period. The physicians who performed all other examinations and TcES were not blinded to study treatment because they were responsible for setting the stimulation parameters.
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 88 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Single (Participant) |
Primary Purpose: | Treatment |
Official Title: | Transkorneale Elektrostimulation Zur Therapie Bei Retinitis Pigmentosa - Eine Prospektive, Randomisierte, Einfach Blinde Folgestudie |
Study Start Date : | July 2011 |
Actual Primary Completion Date : | August 2013 |
Actual Study Completion Date : | February 2014 |

Arm | Intervention/treatment |
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Sham Comparator: Sham
OkuStim is used to determine the phosphene threshold, device is turned on but no stimulation is performed.
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Device: Transcorneal electrostimulation
Other Names:
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Experimental: 150%
OkuStim is used to determine the phosphene threshold, and then to administer transcorneal electrostimulation with a stimulation strength corresponding to 150% of the patient's phosphene threshold.
|
Device: Transcorneal electrostimulation
Other Names:
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Experimental: 200%
OkuStim is used to determine the phosphene threshold, and then to administer transcorneal electrostimulation with a stimulation strength corresponding to 200% of the patient's phosphene threshold.
|
Device: Transcorneal electrostimulation
Other Names:
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- Visual Field, III4e [ Time Frame: one year ]Change in the area measured by kinetic visual field measurement
- Visual Field, V4e [ Time Frame: one year ]Change in the area measured by kinetic visual field measurement
- ERG B-wave [ Time Frame: one year ]
- ERG A-wave [ Time Frame: one year ]
- BCVA [ Time Frame: one year ]Best corrected visual acuity
- VFQ-25 [ Time Frame: one year ]Visual Function Questionnaire (VFQ-25)
- Dark Adaptation [ Time Frame: one year ]Adaptation time, changes in pupil diameter, threshold to fullfield blue and red light is measured with a fullfield stimulus threshold test (FST) on the ESPION ERG machine (Diagnosys).

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Ages Eligible for Study: | 18 Years to 80 Years (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Adult subject with RP (rod-cone dystrophy)
- BCVA 0.02 to 0.9
- Reliable visual field measurements
- Reliable ERG measurements
- Skillful enough to use the device at home
- Able to give consent and take part during the whole study
Exclusion Criteria:
- Diabetic retinopathy
- Neovascularisation of any origin
- After arterial or venous occlusion
- After retinal detachment
- Silicone oil tamponade
- Dry or exudative age-related macular degeneration
- Macular edema
- All forms of glaucoma
- Any form of corneal degeneration that reduces visual acuity
- Systemic diseases that are difficult to control or manage, that could endanger the normal study schedule
- Patients in a permanently poor general condition, which could hinder the regular attendance at control examinations in the clinic
- Forms of mental illness related to the bipolar affective and schizoid-affective disorders, and all forms of dementia
- Simultaneous participation in another interventional study or history of interventions whose effect may still persist

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01837901
Germany | |
Department für Augenheilkunde, Eberhard-Karls-Universität | |
Tübingen, Germany, 72076 |
Principal Investigator: | Florian Gekeler, Prof. Dr. | Eberhard-Karls-Universität Tübingen |
Other Publications:
Responsible Party: | Okuvision GmbH |
ClinicalTrials.gov Identifier: | NCT01837901 |
Other Study ID Numbers: |
EST2 |
First Posted: | April 23, 2013 Key Record Dates |
Results First Posted: | March 18, 2021 |
Last Update Posted: | March 18, 2021 |
Last Verified: | February 2021 |
Transcorneal electrostimulation TcES TES |
Retinitis Retinitis Pigmentosa Retinal Diseases Eye Diseases |
Eye Diseases, Hereditary Retinal Dystrophies Retinal Degeneration Genetic Diseases, Inborn |