Electrical Impedance Properties of Deep Brain Stimulation Electrodes during Long-Term In-Vivo Stimulation in the Parkinson Model of the Rat - Biomedical Engineering Systems and Technologies - page 272

In future experiments, we aim for a comparative study of uni- and bipolar elec-
trodes with a conventional and a modified stimulation program. The quantification of
the DBS effect on locomotion, exploration and anxiety will be analyzed by drug- and
non-drug induced behavioral tests. For these experiments, the operating life of the
battery of the miniaturized DBS stimulator has to be prolonged.
An equivalent circuit model will be developed for a better understanding of the mea-
suring data in order to extract encapsulation parameters. These investigations aim at clari-
fying the phenomenon of the impedance drop at the second day after implantation.
Potential effects at the electrode-tissue interface will be analyzed by histological,
immunochemical and electron-microscopical methods.
Acknowledgements. K.B. is grateful for a stipend of the German Research Founda-
tion (DFG, Research Training Group 1505/1 “welisa”). T.K. acknowledges financing
by a project of the Federal Ministery of Economics and Technology (BMWi, V230-
630-08-TVMV-S-031). Part of the work was conducted within a project financed by
the Federal Ministry of Education and Research (BMBF, FKZ 01EZ0911). The au-
thors are grateful to Dr. R. Arndt for a fruitful cooperation on the stimulator develop-
ment and to Dr. J. Henning for help with the electron microscopy study. We would
like to thank the staff of the electron microscopy center at the University of Rostock's
Medical Faculty for outstanding technical support.
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