Laparoscopic placement of a tined lead electrode on the pudendal nerve with urodynamic monitoring of bladder function during electrical stimulation: an acute experimental study in healthy female pigs

Springerplus. 2014 Jun 24:3:309. doi: 10.1186/2193-1801-3-309. eCollection 2014.

Abstract

Purpose: The aim of this study was to develop a method for standard laparoscopic access to the pudendal nerve in pigs to implant an electrode for chronic neuromodulation studies.

Methods: Using routine laparoscopic surgical techniques, the pudendal nerve was located in 10 female pigs using standardized anatomical landmarks. A tined lead electrode was placed in parallel to the exposed pudendal nerve, and acute unilateral electrical stimulation was performed consecutively on both pudendal nerves. Bladder pressure and perineal skeletal muscle response was monitored during stimulation.

Results: Standard access to the pudendal nerve was successfully established in the pig model with surgical times of approximately 45 minutes for bilateral electrode placement. Acute unilateral stimulation did not evoke bladder responses but resulted in reliable stimulation-dependent activity of the perineal skeletal muscles. The structural integrity of the pudendal nerves was confirmed in all cases.

Conclusions: These results illustrate the effectiveness of laparoscopy for standardised, safe nerve localisation and electrode implantation at the pudendal nerve in pigs. Laparoscopic implantation represents an alternative approach for performing electrode implantation under optical guidance versus the standard approach of percutaneous, neuro-physiological monitored implantation. In the future, pudendal neuromodulation may be used as a supplement to sacral neuromodulation or as a standalone therapeutic approach, depending on the underlying bladder dysfunction.

Keywords: Electrode implantation; Histology; Laparoscopy; Neuromodulation; Pig; Pudendal nerve.