Transcutaneous sacral nerve stimulation for intraoperative verification of internal anal sphincter innervation.

Background: The current standard for pelvic intraoperative neuromonitoring (pIONM) is based on intermittent direct nerve stimulation. This study investigated the potential use of transcutaneous sacral nerve stimulation for non‐invasive verification of pelvic autonomic nerves. Methods: A consecutive series of six pigs underwent low anterior rectal resection. For transcutaneous sacral nerve stimulation, an array of ten electrodes (cathodes) was placed over the sacral foramina (S2 to S4). Anodes were applied on the back, right and left thigh, lower abdomen, and intra‐anally. Stimulation using the novel method and current standard were performed at different phases of the experiment…