A potential therapeutic strategy using a miniature, implantable, wireless nerve stimulation device for treating stress urinary incontinence in rats.

PURPOSE: The present study examined the effects of a miniature, implantable, wireless stimulation device for treating stress urinary incontinence (SUI) in rats.

METHODS

Twenty-four female Sprague-Dawley rats were randomly assigned to three groups: Group 1 (Control), Group 2 (Sham), and Group 3 (Stimulation). All animals underwent vaginal distension (VD) to mimic postpartum SUI. Groups 2 and 3 were implanted with a stimulator in the pelvic floor muscle, but only Group 3 received continuous stimulation for two weeks. Multiple cystometrograms (CMGs) were performed to determine the leak point pressure (LPP) and maximal bladder capacity (MBC).

RESULTS

In the rat model, LPP in Group 1 after VD and after two weeks decreased significantly from baseline (21.1 ± 2.5 and 30.8 ± 5.2 vs. 52.5 ± 6.3 cmH2O, P < 0.001). LPP improved after two weeks compared to after VD (P < 0.01), but did not return to baseline. In Group 2, LPP at baseline, after VD, and after two weeks were 50.8 ± 4.9, 23.1 ± 6.3, and 31.5 ± 6.9 cmH2O, respectively, showing similar changes to Group 1. In Group 3, LPP values were 48.4 ± 4.8, 17.8 ± 3.9, and 48.4 ± 8.5 cmH2O, with significant improvement after two weeks compared to after VD (P < 0.001), returning to baseline. MBC showed no significant differences across conditions.

CONCLUSIONS

The current study demonstrated the effectiveness of the implantable stimulation device for treating SUI in a rat model. Further studies are needed to determine its long-term safety and action mechanism.