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An Ultrasonic Tool for Nerve Conduction Block in Diabetic Rat Models
Published on: October 20, 2017
High frequency electrical conduction block of the pudendal nerve
Narendra Bhadra1, Niloy Bhadra, Kevin Kilgore
1Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Avenue, Wickenden, Cleveland OH 44106-7207, USA.
Journal of Neural Engineering
|May 18, 2006
Summary
High-frequency alternating current (HFAC) stimulation of the pudendal nerve can reversibly block external urethral sphincter (EUS) activity. This technique shows promise for treating bladder-sphincter dyssynergia by restoring urinary voiding control.
Area of Science:
- Neuroscience
- Urology
- Biomedical Engineering
Background:
- Bladder-sphincter dyssynergia impairs urinary voiding.
- Pudendal nerve block offers a potential therapeutic avenue.
- Restoring sphincter control is key for managing voiding dysfunction.
Purpose of the Study:
- To quantify stimulus parameters for high-frequency alternating current (HFAC) sinusoidal waveforms.
- To assess the effectiveness of HFAC stimulation in blocking the external urethral sphincter (EUS).
- To evaluate HFAC pudendal nerve block as a method for restoring urinary voiding.
Main Methods:
- Utilized a proximal electrode on the pudendal nerve to evoke EUS contractions with low-frequency stimuli.
- Applied HFAC (1–30 kHz, 1–10 V) via a distal tripolar nerve cuff electrode.
- Recorded sphincter responses using a catheter-mounted micro-transducer.
Main Results:
- Achieved a fast-onset, reversible motor block of the EUS across tested frequencies.
- Observed three phases in HFAC block: onset response, repetitive firing, and steady-state block.
- Demonstrated a complete EUS block in all subjects with a linear relationship between block thresholds and frequency.
Conclusions:
- HFAC pudendal nerve stimulation effectively produces a quickly reversible block of EUS contractions.
- This HFAC pudendal block is a potentially valuable tool for rehabilitating bladder-sphincter dyssynergia.
- The findings support the use of HFAC for restoring urinary voiding function.
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