Using radio frequency electrical stimulation to block external urethral sphincter contraction and improved voiding efficiency

Block of the external urethral sphincter contractions by using high frequency electrical stimulation of the pudendal nerves is a potential method for inhibiting detrusor sphincter dyssynergia. Most researchers use high frequency electrical stimulation at frequencies between 2kHz to 20kHz, but the parameters and mechanism of this block are not well understood. This paper demonstrated the use of radio frequency electrical stimulation (500kHz) as a method to block the external urethral sphincter contractions and improved voiding efficiency by electrical stimulation of unilateral pudendal nerve efferent axons. The most efficient waveform for conduction was 500kHz (with 0.2 to 1mA) constant-current biphasic sinusoidal, voiding efficiency increased from 53 to 71-92%. These results raise the possibility that using radio frequency electrical stimulation to block external urethral sphincter contraction may provide a new approach for improving voiding in spinal cord injured patients.