Findings from Acute Retinal Stimulation in Blind Patients

  • Peter Walter
  • Gernot Roessler


In acute retinal stimulation experiments retinal stimulators are inserted into the eye, activated, and responses from patients to electrical stimulation are recorded. These tests were done to obtain evidence that the principle of electrical stimulation of the retina works in terms of elicitation of phosphenes or visual perception, respectively. These tests were also done to narrow the parameter range for electrode size and stimulation energy before efforts were undertaken to fabricate a device for chronic stimulation. Results from such tests were also helpful to describe possible perception patterns of patients and also to estimate possible visual acuities after implantation. Usually these tests were done in local anaesthesia so that the patient can respond verbally or by means of an interface to the stimulation. In different experiments rheobase and chronaxie data were reported showing a large variation depending on the device and on individual factors such as the disease state or the proximity between the electrode and the retina. Possible spatial and temporal resolution data were calculated from such experiments demonstrating that the concept of retinal stimulation in blind RP subjects can really help to restore some useful visual function in such patients.


Retinitis Pigmentosa Electrode Array Visual Response Retinal Surface Normal Retina 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Dawson Trick, Litzkow


Intensity e.g. current for stimulation


Light probe




Computer system


Power source


Royal College of Surgeons


Response interface


Retinitis pigmentosa


Stimulus isolation unit






Video documentation


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Department of OphthalmologyRWTH Aachen UniversityAachenGermany

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