Fig. 4: Implantation and in vivo validation of the soft-actuator-assisted peripheral nerve cuffs for minimal invasive surgeries.
From: Electrochemically actuated microelectrodes for minimally invasive peripheral nerve interfaces
a, Conceptual schematic of a flexible nerve cuff actively wrapping around a sciatic nerve for an intimate interface without sutures. b, Cell viability analysis of PPy(DBS) and control groups of glass slides. ES– and ES+ mean without and with the application of voltage stimulation, respectively. Data are shown as mean ± s.d. (n = 6). c, Electrochemical impedance magnitude (bottom) and phase (top) of the neural-recording microelectrodes ahead of and after 1,000 actuating cycles. The solid lines represent mean values and shaded area represent the s.d. d, Self-wrapping of the nerve cuff around a sciatic nerve on the switching of voltage from −0.5 to 0 V. e, Recording baseline noise from an electrode of the soft-actuator-assisted cuff implanted into the sciatic nerve of an anaesthetized rat, shown as a trace (top) and spectrogram (bottom). f, Trace and spectrogram of a representative recording from the sciatic nerve during sensory stimulation in the form of pressing of the hindpaw. Approximate periods of paw presses are indicated as red lines. The green circles indicate the recorded spikes (amplitude 4.5 times above the background noise). The average spike waveform is shown on the right. g, Quantification of noise (green line) and recorded spike (box-plot) amplitudes in response to paw presses, for five implanted actuator-assisted cuffs on five rats: n = 924 (rat 1), 34 (rat 2), 63 (rat 3), 109 (rat 4), 411 (rat 5) spikes. Box plots display the data median (centre line), upper and lower quartiles (bounds of box), 1.5 times the interquartile range (whiskers) and outlier values beyond this range (circles). Scale bars, 1 mm (d); 5 s, 20 µV (e); 5 s, 20 µV, 1 ms, 5 µV (f (from left to right)). Schematic in a created with BioRender.com.
