Authors:
Frederik Ceyssens
1
;
1
;
Marta Bovet Carmona
2
;
2
;
Dries Kil
1
;
1
;
Marjolijn Deprez
3
;
3
;
Bart Nuttin
3
;
3
;
Aya Takeoka
4
;
4
;
Detlef Balschun
2
;
2
and
Robert Puers
1
;
1
Affiliations:
1
ESAT-MICAS, KULeuven, Kasteelpark Arenberg 10, Leuven and Belgium
;
2
Dept. of Psychology, KULeuven, Leuven and Belgium
;
3
Experimental Neurosurgery and Neuroanatomy, KULeuven, Leuven and Belgium
;
4
NERF, Leuven and Belgium
Keyword(s):
Resorbable Materals, Neural Electrode Array, Chronic Recording, Biocompatibility.
Related
Ontology
Subjects/Areas/Topics:
Augmentative and Alternative Communication
;
Biochips and Nanotechnology
;
Biomedical Engineering
;
Biomedical Instruments and Devices
;
Brain-Computer Interfaces
;
Deep Brain Stimulation
;
Devices
;
Health Engineering and Technology Applications
;
Human-Computer Interaction
;
Neural Rehabilitation
;
Neuro-Interface Prosthetic Devices
;
Neuromodulation and Neural Prosthesis
;
NeuroSensing and Diagnosis
;
Neurotechnology, Electronics and Informatics
;
Physiological Computing Systems
Abstract:
Recent work has indicated that it is possible to keep artificial structures such as neural electrode arrays in close contact with neural tissue over chronic timescales, without the formation of scar tissue. The main factor allowing this is a compliance of the structures close to that of the tissue it is embedded in. However, as this results in structures that are too weak to be inserted as such, the question comes up which insertion strategy to use. In this work, we investigate the use of polylactic-co-glycolic acid (PLGA) for this purpose. A process was devised that allows to micromachine needle-shaped PLGA structures, and to embed ultra fine electrode arrays in the needle. The electrode arrays are fabricated using thin-film polyimide technology. They are only 1 micrometer thick, and contain 15 micrometer diameter iridium oxide electrodes aimed at single neuron recording. The implants were tested in vivo over chronic timescales in rats, and were evaluated based on evoked potential a
nd action potential recording as well as post mortem histology (GFAP and NeuN stain). It was concluded that scarring was minimal but still present, with a GFAP scar about 5x smaller in area than the cross section of the PLGA needle itself. The electric recordigs are stable for at least the 4-month duration of the experiment.
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