A Multi-Center, Randomized, Blind, Controlled Clinical Trial of the Safety and Efficacy of Micro Radio Frequency Therapy System for the Treatment of Overactive Bladder

Detrusor nerve radiofrequency ablation (DENERA): Experimental study of safety and efficacy in an ovine model

PURPOSE

The subtrigonal perivesical nerve plexus contains a large proportion of the bladder's innervation. A transurethral radiofrequency ablation approach has successfully denervated this region to alleviate overactive bladder symptoms, with some urothelial heat injury. We report a novel transvaginal RFA device (DENERA) and assess its feasibility and efficacy in denervating the perivesical nerve plexus of in vivo sheep.

METHODS

In 14 adult female in vivo sheep, pulsed radiofrequency energy was applied transvaginally for three cycles of 4 min, maintaining the tissue temperature at 45°C, with 30 s of rest between each cycle. The control group (n = 4) was sacrificed without ablation, and various groups were sacrificed 1 week (n = 3), 4 weeks (n = 4), and 12 weeks (n = 3) after ablation. The bladder subtrigones were harvested then analyzed with H&E, S100, and TH immunostaining to quantify their neural density and neural vacuolization.

RESULTS

The ablation procedure increased the neural vacuolization the most at 1 week and decreased the neural density the most at 4 weeks, with both variables displaying a significant change followed by a slight rebound towards baseline at 12 weeks. The H&E analysis showed that the needles penetrated deep into the subtrigonal detrusor muscle. The sheep recovered from the procedure with no complications or damage in the bladder wall or urothelium.

CONCLUSIONS

This study shows that one DENERA treatment can cause subtrigonal denervation with some rebound afterwards and no complications. DENERA may become a promising OAB treatment option that can ablate the perivesical plexus without harming the urothelium.

Comparison of micro-radiofrequency therapy and tolterodine for the treatment of newly diagnosed overactive bladder: A retrospective cohort study

Purpose

This study aimed to retrospectively compare the efficacy and safety of micro-radiofrequency (RF) therapy through the urethra vs. oral tolterodine tartrate in the treatment of newly diagnosed overactive bladder (OAB).

Materials and methods

In this study, 46 patients who were newly diagnosed with moderate-to-severe OAB were included; 23 of them underwent the micro-RF treatment procedure, and the other 23 patients took tolterodine. Bladder diaries were recorded 3 days before treatment and during the follow-up period on 1, 3, and 7 weeks after micro-RF therapy or oral tolterodine. Micturition parameters including daily voiding times, daily urge urinary incontinence (UI) episodes, daily urgency episodes, mean volume per micturition, post-void residual volume (PVR), maximum urine flow rate (Qmax), overactive bladder symptom score (OABSS), and quality of life (QoL) score were analyzed.

Results

All 46 patients underwent either micro-RF or oral tolterodine treatment, as well as a complete follow-up. The incidence of adverse events in the micro-RF group was 8.7% (2/23), and that in the tolterodine group was 43.5% (10/23). The following two adverse events happened in the micro-RF group: an injury to the urethra during catheterization in a man and a urinary tract infection in a woman, both of which were relieved or disappeared after day 3. The adverse effects in the tolterodine group were mainly dry mouth (4/23), dysuria (5/23), and constipation (8/23), but none of the patients withdrew from the drug therapy. Compared to pre-therapy, all parameters of both groups, including daily voiding times, daily urgency episodes, mean volume per micturition, OABSS, and QoL score, demonstrated significant improvements during follow-up in 7 weeks after therapy, except for daily UI episodes in the tolterodine group, while the above parameters showed bigger improvements in the micro-RF group than in the tolterodine group. Besides, the general treatment efficacy of micro-RF was 73.9% (17/23), which was significantly better than tolterodine (10/23, 43.5%), and the difference was 30.4% [95% CI: 3.4-57.5%, p = 0.036].

Conclusion

In this retrospective study, we found that micro-RF therapy is safe and more effective than oral tolterodine for newly diagnosed moderate-to-severe OAB in a short-term follow-up. Stronger evidence would be provided through a well-designed, prospective, randomized controlled trial.