High frequency electrical conduction block of the pudendal nerve.
A reversible electrical block of the pudendal nerves may provide a valuable method for restoration of urinary voiding in individuals with bladder-sphincter dyssynergia. This study quantified the stimulus parameters and effectiveness of high frequency (HFAC) sinusoidal waveforms on the pudendal nerves to produce block of the external urethral sphincter (EUS). A proximal electrode on the pudendal nerve after its exit from the sciatic notch was used to apply low frequency stimuli to evoke EUS contractions. HFAC at frequencies from 1 to 30 kHz with amplitudes from 1 to 10 V were applied through a conforming tripolar nerve cuff electrode implanted distally. Sphincter responses were recorded with a catheter mounted micro-transducer. A fast onset and reversible motor block was obtained over this range of frequencies. The HFAC block showed three phases: a high onset response, often a period of repetitive firing and usually a steady state of complete or partial block. A complete EUS block was obtained in all animals. The block thresholds showed a linear relationship with frequency. HFAC pudendal nerve stimulation effectively produced a quickly reversible block of evoked urethral sphincter contractions. The HFAC pudendal block could be a valuable tool in the rehabilitation of bladder-sphincter dyssynergia.
Bhadra
Narendra
N
Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Avenue, Wickenden, Cleveland OH 44106-7207, USA.
Bhadra
Niloy
N
Kilgore
Kevin
K
Gustafson
Kenneth J
KJ
D000818:Animals; D002415:Cats; D004558:Electric Stimulation / Q000379:methods*; D004599:Electric Stimulation Therapy / Q000379:methods*; D008297:Male; D009130:Muscle, Smooth / Q000294:innervation* / Q000502:physiology*; D009407:Nerve Block / Q000379:methods*; D001743:Urinary Bladder / Q000294:innervation* / Q000502:physiology*