Transurethral radiofrequency collagen denaturation for the treatment of women with urinary incontinence - Beyond the Abstract

Stress urinary incontinence (SUI) is a bothersome problem that can adversely affect the quality of life of many patients. It is estimated that 38% of women in the United States experience some form of incontinence, of which SUI is the most common. When choosing a treatment modality, the urologist has a wide array of tools in their armamentarium, both surgical and non-surgical. Patient preference often dictates care, and often the prevailing opinion can be that “newer is better”.

In this systematic review, we examined published studies assessing the efficacy of transurethral radiofrequency collagen denaturation for SUI. Originally approved in 2005 under the trade name Renessa® it is now marketed under the trade name Lyrette® by the Verathon company. This treatment is a relatively novel, minimally invasive, device-based intervention that can be conveniently done in the office setting with minimal anesthesia. No incisions are required, as the intervention consists of placing a radiofrequency probe similar to a catheter in the proximal urethra. Several radiofrequency needles are deployed into the urethral submucosa at short time intervals at a total of 36 sites. This treatment has been reported to induce submucosal collagen denaturation to reduce urethral compliance, decrease funneling, and increase the functional length of the urethra.

Like many novel surgical devices, transurethral radiofrequency collagen denaturation was approved through the FDA 510(k) pre-market notification approval process, which requires no additional human testing if the device is deemed substantially similar to a device already on the market. Lyrette® was approved on the basis of previous success of radiofrequency ablation of metastatic liver lesions and benign prostatic hyperplasia (BPH), both notably different disease processes.

Our systematic review of the current literature identified only one small sham-controlled randomized trial of low-quality evidence. In this trial, a sham probe was used in the control arm that lacked needle electrodes and delivered no radiofrequency energy. We found that the trial had incomplete outcome data, a high risk for selective reporting, and a high risk for bias and imprecision. Patients were blinded, however no mention was made as to whether the physicians or outcome assessors were blinded as well. All of these factors severely downgraded the quality of evidence in the trial. Additionally, no statistically significant effect was seen in the primary outcome of a change in the overall International Quality of Life Score (I-QOL). Only a post-hoc secondary analysis of women with moderate to severe SUI at baseline showed a potential benefit.

Overall based on the limited and low quality of evidence, considerable uncertainty remains regarding the true therapeutic efficacy and risks associated with this intervention. Considering the paucity and low quality of evidence regarding the efficacy of transurethral radiofrequency collagen denaturation it cannot be recommended as a treatment modality in the context of other more well established treatment options.

Written by:

Philipp Dahm, MD
Veterans Administration Hospital, University of Minnesota, Minneapolis, Minnesota, USA.

Julia Han, MD
Department of Urology, University of Florida, Gainesville, Florida, USA.

Diana Kang, MD
Department of Urology, University of California Los Angeles, Los Angeles, CA, USA.

Abstract: Transurethral radiofrequency collagen denaturation for the treatment of women with urinary incontinence