Figure 1

Pelvic neuromonitoring principle based on direct nerve stimulation with a hand probe and bioimpedance measurement of the bladder and rectum with a bipolar electrode montage. Contraction of the bladder and rectum smooth muscle in response to direct stimulation of the innervating autonomic nerves results in a change in the muscle tissue impedance compared to the impedance level before contraction. Assessment of stimulation-induced tissue impedance changes allows the nerves to be identified and preserved by the surgeon.