Advancements in minimally invasive treatments for female stress urinary incontinence: Radiofrequency and bulking agents

Intravaginal Pulsed Contractile Radiofrequency for Stress Urinary Incontinence Treatment; A Safety Study

Introduction: Radiofrequency (RF)-based stress urinary incontinence (SUI) treatment, which has quickly attracted attention, is administered in an office setting. This pilot-safety study assessed the efficacy of transvaginal RF treatment in the quality of life (QOL) and frequency of incontinence episodes in women with SUI. Methods: Twenty-eight women suffering from SUI were treated with an intravaginal quadric applicator while a grounding pad was attached in front of their pubes. The first phase is thermic, which will heat up the vaginal wall up to 40°C for 10 minutes. The second step is contraction to stimulate an aerobic exercise of pelvic floor muscles for 20 minutes (pulsed contractile RF at 20-40 watts and 1000-300 kHz with a modulation of 1 to 300 Hz for muscle exercise). It was scheduled for one session per week for 3 sessions. Patients had follow-up visits before and 1, 6 and 12 months following the treatment for one-day voiding diary, Persian version of urinary incontinence QOL questionnaire (I-QOL), Q-tip test, 24 hours-pad test and daily incontinence episodes' number. Results: The patients' mean age, duration of incontinence and median vesical leak point pressure were 41.6±9.6 years, 5.48±6.84 years and 140 cm H₂ O respectively. Significant changes were observed in the mean I-QOL total score and the pad test. Also, a notable reduction was observed in the number of daily leakage episodes and the Q-tip test at any follow-up visit (P=0.001). Conclusion: Preliminary results suggest that transvaginal RF is a convenient method of SUI treatment. Significant changes were observed in the mean I-QOL total score and the pad test. Also, a notable reduction was observed in the number of daily leakage episodes.

A 12-month feasibility study to investigate the effectiveness of cryogen-cooled monopolar radiofrequency treatment for female stress urinary incontinence

INTRODUCTION

The purpose of this early feasibility study was to evaluate the safety and efficacy of a non-ablative, cryogen-cooled, monopolar radiofrequency (CMRF) treatment for female stress urinary incontinence (SUI).

METHODS

Subjects meeting all the inclusion and exclusion criteria were enrolled and randomized into two groups. Subjects in group 1 received one CMRF treatment and subjects in group 2 received two CMRF treatments six weeks apart. Followup visits were performed at one, four, six, and 12 months post-treatment. At each study visit, subjects performed an objective, standardized one-hour pad weight test and completed several patient-reported outcome measures, a seven-day bladder voiding diary, and safety assessments.

RESULTS

Data indicate an improvement in SUI symptoms and quality of life for subjects, as determined by validated SUI-related patient-reported outcomes and the objective one-hour pad weight test, with a >50% reduction in pad weight from baseline for 52% of the subjects at 12 months. In addition to efficacy, the CMRF treatment was well-tolerated and safe.

CONCLUSIONS

The outcome measures evaluated indicate an improvement in SUI symptoms and quality of life. The sustained benefit of the CMRF vaginal treatment at 12 months suggests potential use as an office-based, non-surgical approach to treat mild to moderate SUI.

Early Feasibility Study to Evaluate the Viveve System for Female Stress Urinary Incontinence: Interim 6-Month Report

Background: The purpose of this prospective, investigator-initiated feasibility study is to evaluate the efficacy and safety of nonablative, cryogen-cooled, monopolar radiofrequency (CMRF) treatment for stress urinary incontinence (SUI).

Materials and Methods: Subjects meeting all the inclusion and exclusion criteria were enrolled and divided into two groups. Subjects in Group 1 received a single SUI treatment, and subjects in Group 2 received two SUI treatments ∼6 weeks apart. Follow-up visits are planned for 1, 4, 6, and 12 months post-treatment. At each study visit, subjects are asked to perform a 1-hour pad-weight test (PWT) and to complete the Urogenital Distress Inventory-6 (UDI-6), Incontinence Impact Questionnaire-Short Form (IIQ-7), and International Consultation on Incontinence Modular Questionnaire-Urinary Incontinence-Short Form (ICIQ-UI-SF) questionnaires. In addition, subjects completed 7-day bladder voiding diary and safety assessments.

Results: Preliminary data indicate an improvement in SUI symptoms and quality of life for subjects, as determined by validated SUI-related patient-reported outcomes and the objective 1-hour PWT, with a >50% reduction in pad weight for 68.8% of the Group 1 subjects and 69.2% of the Group 2 subjects at 6 months. Initial review of the bladder voiding diaries suggests that subjects are having fewer urine leakage episodes per day. In addition to efficacy, the CMRF Viveve System was well tolerated and safe.

Conclusions: The endpoints evaluated indicate an improvement in SUI symptoms and quality of life. The sustained benefit of the CMRF vaginal treatment at 6 months suggests potential use as a nonsurgical approach to treat SUI.

Injection of Urethral Bulking Agents

Urethral injection is a safe and minimally invasive method of treating female stress urinary incontinence with multiple bulking agents currently commercially available. Although there are numerous studies that demonstrate efficacy, long-term success is not yet proven. This article aims to describe the mechanism of action and properties of various agents, patient selection factors, available techniques for injection, outcomes of urethral injections, and complications associated with the procedure.

High efficiency diffusion molecular retention tumor targeting

Here we introduce diffusion molecular retention (DMR) tumor targeting, a technique that employs PEG-fluorochrome shielded probes that, after a peritumoral (PT) injection, undergo slow vascular uptake and extensive interstitial diffusion, with tumor retention only through integrin molecular recognition. To demonstrate DMR, RGD (integrin binding) and RAD (control) probes were synthesized bearing DOTA (for (111) In(3+)), a NIR fluorochrome, and 5 kDa PEG that endows probes with a protein-like volume of 25 kDa and decreases non-specific interactions. With a GFP-BT-20 breast carcinoma model, tumor targeting by the DMR or i.v. methods was assessed by surface fluorescence, biodistribution of [(111)In] RGD and [(111)In] RAD probes, and whole animal SPECT. After a PT injection, both probes rapidly diffused through the normal and tumor interstitium, with retention of the RGD probe due to integrin interactions. With PT injection and the [(111)In] RGD probe, SPECT indicated a highly tumor specific uptake at 24 h post injection, with 352%ID/g tumor obtained by DMR (vs 4.14%ID/g by i.v.). The high efficiency molecular targeting of DMR employed low probe doses (e.g. 25 ng as RGD peptide), which minimizes toxicity risks and facilitates clinical translation. DMR applications include the delivery of fluorochromes for intraoperative tumor margin delineation, the delivery of radioisotopes (e.g. toxic, short range alpha emitters) for radiotherapy, or the delivery of photosensitizers to tumors accessible to light.

Bulking agents: a urogynecology perspective

A bulking agent is a material injected into the wall of the urethra to improve urethral coaptation in women suffering from stress incontinence. The concept was initially described in the 1930s when sodium morrhuate and paraffin were used to augment urethral resistance. Sclerosing agents were also used for inducing permanent urethral scaring to improve urinary leakage. Eventually, collagen and autologous fat were found to be efficacious, and only collagen demonstrated proven safety and endured extensive testing, becoming the gold standard for injectable agents. Since then, multiple other products have been developed by the industry, each with its particular success rates and complications.

Urethral bulking: a urology perspective

Urethral bulking therapy (UBT) is a minimally invasive procedure for stress urinary incontinence that is beneficial for properly selected patients. Many different materials are available for UBT, although none fulfill all the qualities of an ideal agent. In general, short-term clinical results are encouraging; however, over longer follow-up, results are disappointing and retreatment is often necessary. Proper patient selection and management of patient expectations are paramount to successful application of UBT.

Radiofrequency for the treatment of stress urinary incontinence in women

Stress urinary incontinence (SUI) is a socially disabling disorder that affects a large population of women around the world. Surgical treatments for SUI typically seek to recapitulate the support of the endopelvic fascia and reduce urethral hypermobility or improve urethral compressive forces. Radio-frequency energy is a potent tool for such treatment, as it is in other medical specialties. The development of transurethral approach techniques affords a major advantage because this nonsurgical procedure can be performed in an office setting with the use of an oral sedative and local anesthesia. The data collected to date suggest that radiofrequency treatment of SUI has promising efficacy and entails a minimal risk of adverse events. Further randomized studies with longer follow-up are needed to assess the ultimate role of this procedure in future urology practice.

Noninvasive thermal coagulation of deep subsurface tissue structures using a laser probe with integrated contact cooling

Cooling methods are used during cosmetic laser surgery to preserve a superficial layer of the skin surface. This study investigates contact cooling for sparing a deeper layer of the tissue surface during laser irradiation of subsurface tissues, with the goal of developing noninvasive laser therapy applications beyond cosmetic surgery. A laser probe was designed and tested for simultaneous laser irradiation and contact cooling of liver tissue, ex vivo. Gross and histologic examination was used to quantify thermal lesion dimensions. Liver lesions of 5.8-mm-diameter were created, while preserving the tissue surface to a depth of 1.5 mm. In vivo animal studies are planned to optimize the laser and cooling parameters for potential clinical applications.

Radiofrequency remodelling of the endopelvic fascia is not an effective procedure for urodynamic stress incontinence in women

The aim of this study was to assess the efficacy and safety of transvaginal radiofrequency remodelling of the endopelvic fascia as a primary procedure for urodynamic stress incontinence due to urethral hypermobility in women. It included 24 patients who had the procedure at two district general hospitals. Outcome measures included the pad test, urodynamic assessment, continence diary, pain scores and operative as well as post-operative complications and assessment was made on recruitment during hospital admission and at 3, 6 and 12 months follow-up. A rising failure rate was noted as early as 3 months, leading to a cumulative cure rate of 45.8% at 12 months follow-up. This low effectiveness could be attributed to inherent weakness of the endopelvic fascia. No major complications were encountered and pain scores were mild.

Emerging periurethral bulking agents for female stress urinary incontinence: is new necessarily better?

Bulking therapy for stress urinary incontinence in women continues to evolve from the standpoint of material science. Several new materials have recently been subjected to clinical trials with the aim of assessing efficacy and safety of these agents for possible device registration. These new additions run the gamut of biologic to synthetic materials, including re-engineered carbon-coated zirconium beads, ethylene vinyl copolymer, calcium hydroxylapatite, silicone, and hyaluronic acid. Trial design and results reporting for bulking agents has also evolved, with the addition of quality-of-life and patient approbation assessments now being included with outcomes for incontinence reduction and adverse events recording. The new agents and recent studies are reviewed within a context of the prior evidence that has supported the use of the bulking strategy for management of symptomatic stress incontinence. Several recent trials have also compared bulking agents with surgical interventions from effectiveness, approbation, and cost vantage points so as to better determine the reasonability of bulking agent use in an era of minimally invasive incontinence surgery.

The emergence of new drugs for overactive bladder

Overactive bladder is a common and distressing problem. Standard therapy is directed towards modifying the detrusor motor sensitivity and response via anticholinergic medication. Currently available medications are reviewed and alternative targets for treatment are presented.

Injection therapy for stress urinary incontinence in adult women

Stress urinary incontinence (SUI) is prevalent in adult women and has a considerable impact on quality of life. However, it often remains undiagnosed and therefore untreated. Noninvasive treatment is likely to be offered in mild cases and may entail pelvic floor muscle re-education, minimally invasive devices or pharmacotherapy. Surgical intervention is widely considered as the only effective option for more severe SUI, although it is not suitable for all patients. Injection therapy with urethral bulking agents represents an alternative minimally invasive procedure and can be used for all types of SUI. Many bulking agents have been developed, although the ideal remains to be discovered. The safety and durability of agents remain a concern. No differences in agents from an efficacy point of view have been found. For many years urethral injection could only be administered endoscopically. The recent development of devices for blind injection has increased the speed and convenience of urethral injection, removing the need for surgical facilities. The subjective cure rate after injection therapy is higher than the objective one. A focus on the patient's wishes and expectations with respect to success and risks of a treatment for SUI is required. In addition, randomized clinical trials are mandatory to establish the place and efficacy of urethral bulking agents compared with conservative therapy (pelvic floor muscle re-education) in treating SUI in adult women.

Subsurface tissue lesions created using an Nd:YAG laser and a sapphire contact cooling probe

BACKGROUND AND OBJECTIVES

This study investigates deep laser coagulation of tissue in combination with contact cooling of the tissue surface for potential use in noninvasive procedures in urology.

STUDY DESIGN/MATERIALS AND METHODS

A laser probe was designed and tested for simultaneous Nd:YAG laser irradiation and sapphire contact cooling of liver and skin tissue samples, ex vivo. Gross and histologic examination was used to quantify thermal lesion dimensions.

RESULTS

Liver lesions measured 5.5 +/- 0.3 mm in diameter, while preserving the tissue surface to a depth of 2.1 +/- 0.2 mm (n = 5). Skin lesions measured 4.3 +/- 0.9 mm in diameter, while preserving the skin surface to a depth of 1.1 +/- 0.2 mm (n = 6). There were no statistical differences in lesion diameter and layer of preserved tissue between contact (sapphire) cooling and prior non-contact (cryogen spray) cooling results for a given tissue type (P > 0.05).

CONCLUSIONS

Noninvasive laser procedures targeting tissue structures for thermal coagulation within a few millimeters of the tissue surface are feasible and may expand the use of combined laser/cooling techniques for applications in urology and general surgery. In vivo animal studies are currently in development to optimize the laser and cooling parameters for potential clinical applications.