Selective recording of the canine hypoglossal nerve using a multicontact flat interface nerve electrode.
A flat-interface nerve electrode (FINE) is presented as a potential solution for using multifascicle nerve recordings as part of a closed-loop control system. To investigate the ability of this electrode to achieve selective recordings at physiological signal-to-noise ratio (SNR), a finite-element model (FEM) of a beagle hypoglossal nerve with an implanted FINE was constructed. Action potentials (AP) were generated at various SNR levels and the performance of the electrode was assessed with a selectivity index (0 < or = SI < or = 1; ability of the electrode to distinguish two active sources). Computer simulations yielded a selective range (0.05 < or = SI < or = 0.76) that was 1) related to the interfiber distance and 2) used to predict the minimum interfiber distance (0.23 mm < or = d < or = 1.42 mm) for selective recording at each SNR. The SI was further evaluated using recorded compound APs elicited from electrically activating the branches of the beagle hypoglossal nerve. For all experiments (n = 7), the selectivity (SI = 0.45 +/- 0.16) was within the range predicted by the FEM. This study suggests that the FINE can record the activity from a multifasciculated nerve and, more importantly, distinguish neural signals from pairs of fascicles at physiologic SNR.
Yoo
Paul B
PB
Neural Engineering Center of the Biomedical Engineering Department, Case Western Reserve University, Cleveland, OH 44106, USA. pby2@duke.edu
Durand
Dominique M
DM
D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D003198:Computer Simulation; D017076:Computer-Aided Design; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation* / Q000379:methods; D004285:Dogs; D004567:Electrodes, Implanted; D004568:Electrodiagnosis / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007002:Hypoglossal Nerve / Q000502:physiology*; D008839:Microelectrodes; D008959:Models, Neurological; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity