Int Neurourol J.  2017 Jun;21(2):102-108. 10.5213/inj.1732754.377.

Effects of Acute Sacral Neuromodulation at Different Frequencies on Bladder Overactivity in Pigs

• Li X
• Liao L
• Chen G
• Wang Z
• Deng H

• KMID: 2387170
• DOI: http://doi.org/10.5213/inj.1732754.377

Abstract

PURPOSE
We investigated the effects of different stimulation frequencies on the inhibition of bladder overactivity by sacral neuromodulation (SNM) in pigs.
METHODS
Implant-driven stimulators were used to stimulate the S3 spinal nerve in 13 pigs. Cystometry was performed by infusing normal saline (NS) or acetic acid (AA). SNM (pulse width, 210 µsec) at frequencies ranging from 5 to 50 Hz was conducted at the intensity threshold at which observable perianal and/or tail movement was induced. Multiple cystometrograms were performed to determine the effects of different frequencies on the micturition reflex.
RESULTS
AA-induced bladder overactivity significantly reduced the bladder capacity (BC) to 34.4%±4.7% of the NS control level (354.4±35.9 mL) (P<0.05). During AA infusion, SNM at 5 Hz did not significantly change the BC (48.1%±6.9% of the NS control level) (P>0.05), but SNM at 15, 30, and 50 Hz significantly increased the BC to 54.5%±7.1%, 55.2%±6.5%, and 57.2%±6.1% of the NS control level (P<0.05), respectively. No significant differences were found among the results obtained using frequencies of 15, 30, and 50 Hz (P>0.05).
CONCLUSIONS
This study demonstrated that 15 Hz was an appropriate frequency for SNM and that frequencies higher than 15 Hz did not lead to better surgical outcomes.

Keyword

Frequency; Neuromodulation; Urinary Bladder, Overactive; Sacral Nerve Stimulation

MeSH Terms

Acetic Acid
Reflex
Spinal Nerves
Swine*
Tail
Urinary Bladder*
Urinary Bladder, Overactive
Urination
Acetic Acid