TY - GEN
T1 - Application of implantable wireless biomicrosystem for monitoring electrode-nerve impedance of animal after sciatic nerve injury
AU - Li, Yu Ting
AU - Chen, Jia Jin Jason
AU - Lin, Chou Ching K.
PY - 2008
Y1 - 2008
N2 - In neural prosthetic applications, it is imperative to monitor the impedance of implantable cuff electrode for the effective sensing and stimulating schemes. With the development of an implantable biomicrosystem, this study was conducted to monitor the time-course changes of electrode-nerve impedance as well as to elicit constant stimulation current for aiding nerve repair in an experimental sciatic nerve injury animal model. For continuous in vivo impedance monitoring, a transcutaneous magnetic coupling technique was adopted for transmitting power and command into the internal module and sending outwards the impedance measurement. The two-terminal and four-terminal methods were adopted for measuring the electrode-tissue interfacing impedance and tissue impedance. To avoid high sampling rate required, a gain-phase detector was utilized for direct output of the magnitude and phase shift of the impedance measurement. Validation tests of impedance measurement and microstimulation function were first performed in an in-vitro impedance model. The differences of measured impedance were less than 10 % in comparison with those measured by precision LCR meter. A self-sizing spiral cuff electrode was fabricated and wrapped around the injured sciatic nerve of New Zealand rabbit for monitoring the changes of electrode-nerve impedance when the animal was awake but partly constrained in a restrainer. In addition, commands for varied level of constant current can be delivered via the magnetic coupling in an attempt to assist the nerve repair.
AB - In neural prosthetic applications, it is imperative to monitor the impedance of implantable cuff electrode for the effective sensing and stimulating schemes. With the development of an implantable biomicrosystem, this study was conducted to monitor the time-course changes of electrode-nerve impedance as well as to elicit constant stimulation current for aiding nerve repair in an experimental sciatic nerve injury animal model. For continuous in vivo impedance monitoring, a transcutaneous magnetic coupling technique was adopted for transmitting power and command into the internal module and sending outwards the impedance measurement. The two-terminal and four-terminal methods were adopted for measuring the electrode-tissue interfacing impedance and tissue impedance. To avoid high sampling rate required, a gain-phase detector was utilized for direct output of the magnitude and phase shift of the impedance measurement. Validation tests of impedance measurement and microstimulation function were first performed in an in-vitro impedance model. The differences of measured impedance were less than 10 % in comparison with those measured by precision LCR meter. A self-sizing spiral cuff electrode was fabricated and wrapped around the injured sciatic nerve of New Zealand rabbit for monitoring the changes of electrode-nerve impedance when the animal was awake but partly constrained in a restrainer. In addition, commands for varied level of constant current can be delivered via the magnetic coupling in an attempt to assist the nerve repair.
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U2 - 10.1109/ISCAS.2008.4541617
DO - 10.1109/ISCAS.2008.4541617
M3 - Conference contribution
AN - SCOPUS:51749110452
SN - 9781424416844
T3 - Proceedings - IEEE International Symposium on Circuits and Systems
SP - 1112
EP - 1115
BT - 2008 IEEE International Symposium on Circuits and Systems, ISCAS 2008
T2 - 2008 IEEE International Symposium on Circuits and Systems, ISCAS 2008
Y2 - 18 May 2008 through 21 May 2008
ER -