A New Implanted Posterior Tibial Nerve Stimulator for the Treatment of Overactive Bladder Syndrome: 3-Month Results of a Novel Therapy at a Single Center.

PURPOSE: This study was designed to investigate the safety and performance of a new implantable system for tibial nerve stimulation for overactive bladder symptoms. MATERIALS AND METHODS: A battery-free stimulation device for tibial nerve stimulation (BlueWind Medical, Herzliya, Israel) was implanted in 15 patients. Safety and efficacy assessments were done at 3 months after activation with a 3-day bladder diary, a 24-hour pad test and 2 quality of life questionnaires. RESULTS: Two males and 13 females were enrolled in the study. Mean age was 54 years (range 19 to 72). Five of 15 patients were previously treated with percutaneous tibial nerve stimulation and 12 experienced urgency urinary incontinence. Median operative time was 34 minutes. At 3 months of followup a significant change was seen in 24-hour frequency from a mean ± SD of 11.8 ± 3.5 to 8.1 ± 2.0 times per day (p = 0.002), the number of severe urinary urgency episodes from 6.5 ± 5.1 to 2.0 ± 2.1 times per day (p = 0.002), the number of severe incontinence episodes from 2.8 ± 5.2 to 0.3 ± 0.4 episodes per day (p = 0.017), urinary loss per day from 243 ± 388 to 39 ± 55 gm (p = 0.038) and improvement in quality of life. After implantation, 3 patients received prolonged antibiotic treatment and 3 received pain medication for 1 week. In 1 patient the device was explanted due to pain and swelling suspicious for infection, although tissue cultures did not reveal a bacterial infection. CONCLUSIONS: This novel posterior tibial nerve stimulator is safe and easy to implant with good clinical results.

Electroanatomical Mapping of the Urinary Bladder.

A noncontact mapping system (EnSite) was used for electroanatomical mapping of the bladder simultaneously with pressure flow study in three women with lower urinary tract symptoms. We selected the periods of obvious detrusor activity. Data were processed to remove baseline drift, and an envelope of electrovesicography (EVG) data was created. The correlation coefficient for the correlation between between the EVG envelope and the detrusor pressure (Pdet) was calculated. Bladder geometry was successfully created in all 3 patients. Simultaneous recording of EVG and pressure flow data was successful in 1 patient. Scatter plots were made of the highest correlation coefficient, showing a positive correlation between the Pdet and the envelope, and negative correlation between abdominal pressure (Pabd) and the envelope. Minimal electrical activity could be observed. Significant weak to moderate correlation coefficients were found for the correlations between Pdet and EVG and between Pabd and EVG.