Safety evaluation of “retina implant alpha IMS”—a prospective clinical trial

  • Veronique B. D. Kitiratschky
  • Katarina StinglEmail author
  • Barbara Wilhelm
  • Tobias Peters
  • Dorothea Besch
  • Helmut Sachs
  • Florian Gekeler
  • Karl Ulrich Bartz-Schmidt
  • Eberhart Zrenner
Basic Science



To restore vision in patients with retinitis pigmentosa, several types of electronic devices have been developed to stimulate neurons at different levels along the visual pathway. Subretinal stimulation of the retina with the Retina Implant Alpha IMS (Retina Implant AG, Reutlingen, Germany) has been demonstrated to provide useful vision in daily life. Here we evaluated the safety of this device.


An interventional, prospective, multi-center, single-arm study was conducted in patients with retinitis pigmentosa with the Retina Implant Alpha IMS. The results from the first nine patients of a single center regarding safety of the device are reported. Any untoward medical occurrence related or unrelated to the tested device was documented and evaluated.


Nine adult subjects were included in the study at the Tübingen site. Seventy-five adverse events occurred in total, and 53 affected the eye and its adnexa. Thirty-one ocular adverse events had a relationship to the implant that was classified as “certain” while 19 had a probable or possible relationship; three had no relationship to the implant. Thirty-nine ocular adverse events resolved without sequelae, two resolved with sequelae, 11 remained unresolved, and in one the status was unknown. The intensity of ocular adverse events was mild in the majority of cases (n = 45), while six were of moderate and two of severe intensity. There was no non-ocular adverse event with certain relationship to the device. One subject lost light perception (without light localization) in her study eye.


In conclusion, this prospective study, “Safety and Efficacy of Subretinal Implants for Partial Restoration of Vision in Blind Patients,” shows that the Retina Implant Alpha IMS is an option for restoring vision using a subretinal stimulation device with a clinically acceptable safety profile.


Retina implant Alpha IMS Artificial vision Retintis pigmentosa Retinal degeneration Prospective clinical trial 


Conflict of interest

Conflicts of interest are as follows: Veronique Kitiratschky: None. Katarina Stingl: Employed by University of Tübingen through a grant provided by Retina Implant AG, Reutlingen for the clinical trial, travel support. Eberhart Zrenner: Stock ownership in Retina Implant AG, Reutlingen, paid consultant, holder of patents as inventor/developer, travel support from Retina Implant AG, Reutlingen. Florian Gekeler, Helmut Sachs: Stock ownership in Retina Implant AG, Reutlingen, paid consultants. Karl-Ulrich Bartz-Schmidt, Dorothea Besch: No financial conflicts of interest. Tobias Peters, Barbara Wilhelm: CRO of the trial on behalf of Retina Implant AG, Reutlingen.

Authors have full control of all primary data and agree to allow the Graefes Archives of Ophthalmology to review their data if requested.


Retina Implant AG, Reutlingen, Germany

Tistou & Charlotte Kerstan Stiftung, Tübingen, Germany

Bernstein Center for Computational Neuroscience Tübingen, Germany, Project A3

This work was supported by the Deutsche Forschungsgemeinschaft (EXC 307, CIN, Senior-Professorship to E.Z.)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Veronique B. D. Kitiratschky
    • 1
  • Katarina Stingl
    • 1
    Email author
  • Barbara Wilhelm
    • 1
  • Tobias Peters
    • 1
  • Dorothea Besch
    • 1
  • Helmut Sachs
    • 2
  • Florian Gekeler
    • 1
    • 3
  • Karl Ulrich Bartz-Schmidt
    • 1
  • Eberhart Zrenner
    • 1
    • 4
  1. 1.Centre for OphthalmologyUniversity of TübingenTübingenGermany
  2. 2.AugenklinikKrankenhaus Dresden FriedrichstadtDresdenGermany
  3. 3.KatharinenhospitalStuttgartGermany
  4. 4.Werner Reichardt Centre for Integrative Neuroscience (CIN), Centre for OphthalmologyUniversity of TübingenTübingenGermany

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