title: Long-term stimulation and recording with a penetrating microelectrode array in cat sciatic nerve.
abstract: We studied the consequences of long-term implantation of a penetrating microelectrode array in peripheral nerve over the time course of 4-6 mo. Electrode arrays without lead wires were implanted to test the ability of different containment systems to protect the array and nerve during contractions of surrounding muscles. Treadmill walking was monitored and the animals showed no functional deficits as a result of implantation. In a different set of experiments, electrodes with lead wires were implanted for up to 7 mo and the animals were tested at 2-4 week intervals at which time stimulation thresholds and recorded sensory activity were monitored for every electrode. It was shown that surgical technique highly affected the long-term stimulation results. Results between measurement sessions were compared, and in the best case, the stimulation properties stabilized in 80% of the electrodes over the course of the experiment (162 days). The recorded sensory signals, however, were not stable over time. A histological analysis performed on all implanted tissues indicated that the morphology and fiber density of the nerve around the electrodes were normal.
authors.affiliation: Center for Neural Interfaces, Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA. almut@CYBERKINETICS.com
authors.forename: Almut
authors.initials: A
authors.lastname: Branner
authors.forename: Richard B
authors.initials: RB
authors.lastname: Stein
authors.forename: Eduardo
authors.initials: E
authors.lastname: Fernandez
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Aoyagi
authors.forename: Richard A
authors.initials: RA
authors.lastname: Normann
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D002415:Cats; D004558:Electric Stimulation / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D004576:Electromyography / Q000295:instrumentation / Q000379:methods; D019544:Equipment Failure Analysis; D008124:Locomotion / Q000502:physiology; D008839:Microelectrodes; D018670:Monitoring, Ambulatory / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D018482:Muscle, Skeletal / Q000294:innervation* / Q000502:physiology*; D019919:Prosthesis Implantation / Q000009:adverse effects / Q000379:methods; D012584:Sciatic Nerve / Q000166:cytology* / Q000293:injuries / Q000502:physiology*