Sacral neuromodulation is an internationally studied, minimally invasive procedure that has an excellent success rate with Overactive Bladder Syndrome (OBS) featuring the symptoms of frequency, urgency, urgency incontinence and nocturia. It has also been successful in treating non-obstructive urinary retention in women.
Over the past 15 years, the author has conducted a comprehensive study of sacral and pudendal neuromodulation, both in practice and in review of electronic medical records (EMR). In 2000, it was conventional practice in Stage 1 procedures to employ a local and intravenous sedation anesthetic and to consult with the patient intraoperatively to analyze the degree and location of sensation. The expectation was that when sensation was localized to the bladder area, a better therapeutic result (i.e., diminution of OBS symptoms) would be realized. Soon it became apparent that sensory/motor provocation was longer and less effective than the alternative approach of a general anesthetic and strict motor provocation, in which no attention was paid to the intraoperative intensity or location of the provocation.
Our results were consistent with those found in a retrospective double cohort analysis: sensory/motor provocation is less efficacious in several important parameters. Strict motor provocation realized a statistically significant improvement [p<0.001] in Urinary Distress Inventory (short form) preoperative and post-operative scores and a reduction in the number of voids per 24 hours. Mean operative time for motor provocation was 29.5 minutes, compared to 59.3 minutes for the sensory/motor approach. This is an important finding, as medical expenditures are now closely supervised, and recommendations may be applied to surgeons to avoid procedures with a significant time disparity if an alternative achieves equal or better patient outcomes.
Unfortunately, a comparison of relative procedure costs (direct and indirect) was not possible. Another important realization was the disproportionately large number of annual sessions to reprogram the implantable pulse generator (IPG). While the average is 1.0 – 1.5 visits per year, our sensory/motor provocation patients returned, on average, 2.8 times per year. Overall patient satisfaction was marginally better with motor provocation but not to the point of statistical significance. In summary, motor provocation achieves a significant improvement of urinary symptoms, reduced operating times, and fewer office reprogramming sessions, with a mean follow-up of ten years. We encourage consideration for prospective studies to confirm our results.
Written by:
Marinkovic SP, Gillen LM, Marinkovic CM.
Department of Urology, Detroit Medical Center, Detroit, MI, USA.