Intraoperative Predictors of Sacral Neuromodulation Implantation and Treatment Response: Results From the ROSETTA...

We determined the utility of intraoperative data in predicting sacral neuromodulation outcomes in urgency urinary incontinence.

Intraoperative details of sacral neuromodulation stage 1 were recorded during the prospective, randomized, multicenter ROSETTA trial, including responsive electrodes, amplitudes, and response strengths (motor and sensory Likert scales). Stage 2 implant was performed for stage 1 success on 3-day diary with 24-month follow-up. An intraoperative amplitude response score for each electrode was calculated ranging from 0 (no response) to 99.5 (maximum response, 0.5 V). Predictors for stage 1 success and improvement at 24 months were identified by stepwise logistic regression confirmed with least absolute shrinkage and selection operator and stepwise linear regression.

Intraoperative data from 161 women showed 139 (86%) had stage 1 success, which was not associated with number of electrodes generating an intraoperative motor and/or sensory response, average amplitude at responsive electrodes, or minimum amplitude-producing responses. However, relative to other electrodes, a best amplitude response score for bellows at electrode 3 was associated with stage 1 failure, a lower reduction in daily urgency urinary incontinence episodes during stage 1, and most strongly predicted stage 1 outcome in logistic modeling. At 24 months, those who had electrode 3 intraoperative sensory response had lower mean reduction in daily urgency urinary incontinence episodes than those who had no response.

Specific parameters routinely assessed intraoperatively during stage 1 sacral neuromodulation for urgency urinary incontinence show limited utility in predicting both acute and long-term outcomes. However, lead position as it relates to the trajectory of the sacral nerve root appears to be important.