Optimizing the design of bipolar nerve cuff electrodes for improved recording of peripheral nerve activity

• Published in: Journal of neural engineering 2017-06, Vol.14 (3), p.036015-036015
• Main Authors: Sabetian, Parisa, Popovic, Milos R, Yoo, Paul B
• Format: Article
• Language: English
• Subjects: Action Potentials - physiology; Animals; bipolar recording configuration; Computer Simulation; Computer-Aided Design; directional nerve recording; Electric Impedance; Electrodes; Electrodes, Implanted; Equipment Design - methods; Equipment Failure Analysis - methods; Feasibility Studies; Female; Finite Element Analysis; Models, Neurological; nerve cuff electrode; neurostimulation; peripheral nerve recording; Peripheral Nerves - physiology; Rats; Rats, Sprague-Dawley; Reproducibility of Results; Sensitivity and Specificity; Signal-To-Noise Ratio
• ISSN: 1741-2560; 1741-2552
• DOI: 10.1088/1741-2552/aa6407

Objective. Differential measurement of efferent and afferent peripheral nerve activity offers a promising means of improving the clinical utility of implantable neuroprostheses. The tripolar nerve cuff electrode has historically served as the gold standard for achieving high signal-to-noise ratios (SNRs) of the recordings. However, the symmetrical geometry of this electrode array (i.e. electrically-shorted side contacts) precludes it from measuring electrical signals that can be used to obtain directional information. In this study, we investigated the feasibility of using a bipolar nerve cuff electrode to achieve high-SNR of peripheral nerve activity. Approach. A finite element model was implemented to investigate the effects of electrode design parameters-electrode length, electrode edge length (EEL), and a conductive shielding layer (CSL)-on simulated single fiber action potentials (SFAP) and also artifact noise signals (ANS). Main results. Our model revealed that the EEL was particularly effective in increasing the peak-to-peak amplitude of the SFAP (319%) and reducing the common mode ANS (67%) of the bipolar cuff electrode. By adding a CSL to the bipolar cuff electrode, the SNR was found to be 65.2% greater than that of a conventional tripolar cuff electrode. In vivo experiments in anesthetized rats confirmed that a bipolar cuff electrode can achieve a SNR that is 38% greater than that achieved by a conventional tripolar cuff electrode (p