Intraoperative electrical stimulation of cavernous nerves with monitoring of intracorporeal pressure to confirm nerve sparing during radical prostatectomy: Early clinical results

Background: We performed intraoperative cavernous nerve stimulation with an intracavernous pressure (ICP) monitoring system to confirm nerve sparing during radical pelvic surgery and assessed the results. Methods: Nineteen cases of radical prostatectomy and three of radical cystoprostatectomy were examined. Electrical stimulation of the site where the neurovascular bundle (NVB) was determined to run was performed and changes in ICP were measured before and after prostate removal. Results: Of the 22 patients, bilateral NVBs were preserved in six patients while unilateral NVB was preserved in 16. Before dissection, all NVBs examined exhibited positive responses (ICP changes of>5 mmHg) to nerve stimulation. After removal of the prostate, positive responses were observed in 22 (79%) of 28 macroanatomically preserved NVBs. Of 16 sides on which the NVB was not preserved, there were positive responses in five (31%). In these patients, some nerve fibers were macroscopically observed lateral to the original site of NVB. Finally, bilateral or unilateral nerve sparing was confirmed electrophysiologically in 20 (91%) of the 22 patients. Conclusion: Intraoperative stimulation of the NVB while monitoring ICP changes is a simple and reliable method of accurately evaluating the preservation of cavernous nerves. This system may provide further insight into the mechanism of postoperative erectile dysfunction.