Injectable biomaterials for the treatment of stress urinary incontinence: their potential and pitfalls as urethral bulking agents

The SDF-1/CXCR4 axis is involved in adipose-derived stem cell migration

BACKGROUND

Intravenous injection of adipose-derived stem cells (ADSCs) can improve the urinary function of stress urinary incontinence (SUI) model rats and C-X-C chemokine receptor type 4 (CXCR4)-positive ADSCs are found in urethral tissues. The CXCR4 ligand stromal cell-derived factor-1 (SDF-1) is highly expressed in urinary incontinence model rats. In this study, we investigated the involvement of the SDF-1/CXCR4 axis in the homing of ADSCs.

METHODS

ADSCs were isolated from rats and purified. The levels of CXCR4 and CXCR7 were determined by western blot analysis and immunofluorescence assays following stimulation with SDF-1. Hypoxia conditioning was performed to treat the cells in vitro, following which the messenger RNA (mRNA) and protein level of SDF-1, CXCR4, and CXCR7 were estimated.

RESULTS

We found that CXCR4 and CXCR7 were expressed in ADSCs at passage zero (P0), P1, and P3, and the expression of both increased after SDF-1 stimulation. The level of expression of the mRNAs and proteins of SDF-1, CXCR4, and CXCR7 in ADSCs was higher after hypoxic conditioning. We then knocked down CXCR4 or CXCR7 using small interfering RNAs and found that the mRNA levels of CXCR4 and CXCR7 were considerably downregulated in the si-CXCR4/7-transfected cells. We also found that the SDF-1/CXCR4 axis was required for the migration of ADSCs. The phosphorylation levels of Janus kinase (JAK), protein kinase B (AKT), and extracellular regulated protein kinase significantly increased in SDF-1-stimulated ADSCs. However, the migration of ADSCs was suppressed when the corresponding specific inhibitors were used to block JAK and AKT signaling or silence CXCR4, whereas no significant change was observed in the migratory ability of ADSCs when the ERK pathway was blocked or CXCR7 was silenced.

CONCLUSIONS

The SDF-1/CXCR4 axis is involved in the migration of ADSCs and may play a role in the migrate of ADSCs in SUI.

Therapies Based on Adipose-Derived Stem Cells for Lower Urinary Tract Dysfunction: A Narrative Review

Lower urinary tract dysfunction often requires tissue repair or replacement to restore physiological functions. Current clinical treatments involving autologous tissues or synthetic materials inevitably bring in situ complications and immune rejection. Advances in therapies using stem cells offer new insights into treating lower urinary tract dysfunction. One of the most frequently used stem cell sources is adipose tissue because of its easy access, abundant source, low risk of severe complications, and lack of ethical issues. The regenerative capabilities of adipose-derived stem cells (ASCs) in vivo are primarily orchestrated by their paracrine activities, strong regenerative potential, multi-differentiation potential, and cell–matrix interactions. Moreover, biomaterial scaffolds conjugated with ASCs result in an extremely effective tissue engineering modality for replacing or repairing diseased or damaged tissues. Thus, ASC-based therapy holds promise as having a tremendous impact on reconstructive urology of the lower urinary tract.

Prophylactic antibiotics for preventing infection after continence surgery in women with stress urinary incontinence

BACKGROUND

Surgical options for treating stress urinary incontinence (SUI) are usually explored after conservative interventions have failed. Surgeries fall into two categories: traditional techniques (open surgery) and minimally invasive procedures, such as laparoscopic procedures, midurethral sling and injections with urethral bulking agents. Postsurgery infections, such as infections of the surgical site or urinary tract, are common complications. To minimise the risk of postoperative bacterial infections, prophylactic antibiotics may be given before or during surgery.  OBJECTIVES: To assess the effects of prophylactic antibiotics for preventing infection following continence surgery in women with stress urinary incontinence.  SEARCH METHODS: We searched the Cochrane Incontinence Specialised Register, which contains trials identified from CENTRAL, MEDLINE, MEDLINE In-Process, MEDLINE Epub Ahead of Print, CINAHL, ClinicalTrials.gov and WHO ICTRP; and handsearched journals and conference proceedings to 18 March 2021. We also searched the reference lists of relevant articles.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs assessing prophylactic antibiotics in women undergoing continence surgery to treat SUI.

DATA COLLECTION AND ANALYSIS

Two review authors selected potentially eligible trials, extracted data and assessed risk of bias. We expressed results as risk ratios (RR) for dichotomous outcomes and as mean differences (MD) for continuous outcomes, both with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach.

MAIN RESULTS

We identified one quasi-RCT and two RCTs, involving a total of 390 women. One study performed retropubic urethropexy surgery requiring a transverse suprapubic incision, while the other two studies performed midurethral sling surgery. It should be noted that none of the included studies clearly specified the timing of outcome assessment. We are very uncertain whether prophylactic antibiotics (cefazolin) have an effect on surgical site infections (RR 0.56, 95% CI 0.03 to 12.35; 2 studies, 85 women; very low-certainty evidence) or urinary tract infections or bacteriuria (RR 0.84, 95% CI 0.05 to 13.24; 2 studies, 85 women; very low-certainty evidence). The effect of prophylactic antibiotics (cefazolin) on febrile morbidity is also uncertain (RR 0.08, 95% CI 0.00 to 1.29; 2 studies, 85 women; very low-certainty evidence). We are very uncertain whether prophylactic antibiotics (cefazolin) have any effect on mesh exposure (RR 0.32, 95% CI 0.01 to 7.61; 1 study, 59 women; very low-certainty evidence). None of the three included studies described the assessment of adverse events from antibiotic use, sepsis or bacteraemia in their reports.

AUTHORS' CONCLUSIONS

Only limited data are available from the three included studies and, overall, the certainty of evidence was very low. Moreover, the three included studies evaluated different surgical procedures and dosages of antibiotic administration. Thus, there is insufficient evidence to support or refute the use of prophylactic antibiotics to prevent infection following anti-incontinence surgery. In addition, there were no data regarding adverse effects of prophylactic antibiotics. More RCTs are required.

In-vitro cellular and in-vivo investigation of ascorbic acid and β-glycerophosphate loaded gelatin/sodium alginate injectable hydrogels for urinary incontinence treatment

Urinary incontinence is one of the most common disorders especially in adult women. In this study, cellular and in-vivo analyses were performed on (3-glycidyloxypropyl) trimethoxysilane (GPTMS) and CaCl2 cross-linked alginate and gelatin hydrogels containing β-glycerophosphate and ascorbic acid to evaluate the regenerative potential as injectable compression agents for the treatment of urinary incontinence. The hydrogels were prepared with different percentages of components and were named as GA1 (7.2% w/v gelatin, 6% w/v sodium alginate, 0.5:1w/w GPTMS, CaCl2 1% (wt) sodium alginate, 50 μg/mL ascorbic acid, 1.5 mg/mL β-glycerophosphate), GA2 (10% w/v gelatin, 8.5% w/v sodium alginate, 0.5:1 w/w GPTMS, CaCl2 1% (wt) sodium alginate, 50 μg/mL ascorbic acid, 1.5 mg/mL β-glycerophosphate), and GA3 (10% (w/v) gelatin, 8.5% w/v sodium alginate, 1:1 w/w GPTMS, CaCl2 1% (wt) sodium alginate, 50 μg/mL ascorbic acid, 1.5 mg/mL β-glycerophosphate) hydrogels. The results of cell studies showed that although all three samples supported cell adhesion and survival, the cellular behavior of the GA2 sample was better than the other samples. Animal tests were performed on the optimal GA2 sample, which showed that this hydrogel repaired the misfunction tissue in a rat model within 4 weeks and the molecular layer thickness was reached the normal tissue after this duration. It seems that these hydrogels, especially GA2 sample containing 10% (w/v) gelatin, 8.5% (w/v) sodium alginate, 0.5:1 (w/w) GPTMS, CaCl2 1% (wt) sodium alginate, 50 μg/mL ascorbic acid, and 1.5 mg/mL β-glycerophosphate, can act as an injetable hydrogel for urinary incontinence treatment without the need for repeating the injection.

Comparison of synthetic mesh erosion and chronic pain rates after surgery for pelvic organ prolapse and stress urinary incontinence: a systematic review

BACKGROUND

The aim of this study is to systematically compare rates of erosion and chronic pain after mesh insertion for pelvic organ prolapse (POP) and stress urinary incontinence (SUI) surgery.

METHODS

A systematic electronic search was performed on studies that evaluated the incidence of erosion and chronic pain after mesh insertion for POP or SUI. The primary outcome measurement was to compare mesh erosion rates for POP and SUI surgery. Secondary outcome measurements were incidence of de novo pain and a comparison of patient demographics for both surgeries.

RESULTS

Twenty-six studies on 292,606 patients (n = 9077 for POP surgery and n = 283,529 for SUI surgery) met the inclusion criteria. Median follow-up was 26.38 ± 22.17 months for POP surgery and 39.33 ± 27.68 months for SUI surgery. Overall, the POP group were older (p < 0.0001) and had a lower BMI (p < 0.0001). Mesh erosion rates were significantly greater in the POP group compared to the SUI group (4% versus 1.9%) (OR 2.13; 95% CI 1.91-2.37; p < 0.0001). The duration from surgery to onset of mesh erosion was 306.84 ± 183.98 days. There was no difference in erosion rates between abdominal and transvaginal mesh for POP. There was no difference in erosion rates between the transobturator and retropubic approach for SUI. The incidence of chronic pain was significantly greater in the POP group compared to the SUI group (6.7% versus 0.6%) (OR 11.02; 95% CI 8.15-14.9; p < 0.0001). The duration from surgery to onset of chronic pain was 325.88 ± 226.31 days.

CONCLUSIONS

The risk of mesh erosion and chronic pain is significantly higher after surgery for POP compared to SUI. These significant complications occur within the first year after surgery.

Use of bioactive extracellular matrix fragments as a urethral bulking agent to treat stress urinary incontinence

Injection of urethral bulking agents is a low-risk, minimally invasive surgical procedure to treat stress urinary incontinence (SUI). In this study, we developed a promising injectable bulking agent comprising extracellular matrix fragments of adipose-derived stem cell sheets (ADSC ECM) and investigated its effectiveness in urethral bulking therapy. The structural integrity and proteins of ADSC sheet ECM were well retained in decellularized ADSC ECM fragments. To locate transplanted ADSC ECM fragments, they were labeled with ultrasmall super-paramagnetic iron oxide nanoparticles, which enabled in vivo monitoring after implantation in a SUI rat model for up to 4 weeks. When ADSC ECM fragments were injected into the rat urethra, they became fully integrated with the surrounding tissue within 1 week. Four weeks after transplantation, host cells had regenerated within the ADSC ECM fragment injection area. Moreover, new smooth muscle tissue had formed around the ADSC ECM fragments, as confirmed by positive staining of myosin. These results indicate that injection of ECM fragments may be a promising minimally invasive approach for treating SUI.

Polydimethylsiloxane Erosion as a Cause for Recurrent Urinary Tract Infections

Background: Urethral bulking agents are commonly used for the management of stress urinary incontinence (SUI). Little long-term data exist for these agents, with few reports of migration or urethral erosion. Case Presentation: We describe a unique case of a woman who received a midurethral sling 3 years after receiving an injection of the urethral bulking agent, polydimethylsiloxane, because of persistent SUI. Her subsequent recurrent urinary tract infections led to the identification of a bladder neck erosion of the urethral bulking agent with a concomitant calcification. Conclusion: When irritative voiding symptoms are experienced in patients who have received urethral bulking agents, erosion must be considered. Furthermore, little is known regarding the definitive management of SUI in patients that have previously received an injection of a urethral bulking agent.

Magnetic targeting of super-paramagnetic iron oxide nanoparticle labeled myogenic-induced adipose-derived stem cells in a rat model of stress urinary incontinence

Cell-based injectable therapy utilizing stem cells is a promising approach for the treatment of stress urinary incontinence (SUI). Applying a magnetically controlled cell delivery approach has enormous potential to enhance cell retention capability within the specified site. To assess the therapeutic efficacy of cellular magnetic targeting, we applied an external magnetic force to target an adipose-derived stem cell based therapy in a rat model of SUI. The results revealed that magnetic attraction of transplanted cells under the magnetic field was generated by cell uptake of superparamagnetic iron oxide nanoparticles in vitro. More importantly, magnetic targeting improved the retention rate of transplanted cells and facilitated the restoration of sphincter structure and function in a rat SUI model according to the results of histological examination and urodynamic testing. Therefore, magnetically guided targeting strategy might be a potential therapy method for treatment of SUI.

Regenerative medicine and injection therapies in stress urinary incontinence

Stress urinary incontinence (SUI) is a common and bothersome condition. Anti-incontinence surgery has high cure rates, but concerns about mesh tapes have resulted in the resurgence of surgical procedures that involve increased abdominopelvic dissection and morbidity. Injection therapy with urethral bulking agents or stem cell formulations have been developed as minimally invasive alternatives. Many synthetic and biological bulking agents have been trialled, but several have been discontinued owing to safety concerns. The use of Macroplastique and Contigen has the largest evidence base, but, overall, success rates seem to be similar between the various agents and positive outcomes are poorly sustained for more than 6 months. Furthermore, subjective cure rates, although initially high, also deteriorate over time. The available data consistently demonstrate manifestly poorer outcomes for injection therapies than for surgery. Stem cell treatments are thought to functionally regenerate the urethral sphincter in patients with suspected intrinsic sphincter deficiency. Autologous adipose and muscle-derived stem cells seem to be the intuitive cell source, as they are comparatively abundant, can be harvested and cause minimal donor site morbidity. To date, only a few small clinical studies have been reported and most data are derived from animal models. The success rates of stem cell injection therapies seem to be comparable with those of bulking agents.

Regenerative potential of human dental pulp stem cells in the treatment of stress urinary incontinence: In vitro and in vivo study

OBJECTIVES

To evaluate the regenerative potential of human dental pulp stem cells (hDPSCs) in an animal model of stress urinary incontinence (SUI). SUI, an involuntary leakage of urine, is due to physical stress involving an increase in bladder pressure and a damage of external urethral sphincter affecting muscles and nerves. Conventional therapies can only relieve the symptoms. Human DPSCs are characterized by peculiar stemness and immunomodulatory properties and might provide an alternative tool for SUI therapy.

MATERIALS AND METHODS

In vitro phase: hDPSCs were induced towards the myogenic commitment following a 24 hours pre-conditioning with 5-aza-2'-deoxycytidine (5-Aza), then differentiation was evaluated. In vivo phase: pudendal nerve was transected in female rats to induce stress urinary incontinence; then, pre-differentiated hDPSCs were injected in the striated urethral sphincter. Four weeks later, urethral sphincter regeneration was assayed through histological, functional and immunohistochemical analyses.

RESULTS

Human DPSCs were able to commit towards myogenic lineage in vitro and, four weeks after cell injection, hDPSCs engrafted in the external urethral sphincter whose thickness was almost recovered, committed towards myogenic lineage in vivo, promoted vascularization and an appreciable recovery of the continence. Moreover, hDPSCs were detected within the nerve, suggesting their participation in repair of transected nerve.

CONCLUSIONS

These promising data and further investigations on immunomodulatory abilities of hDPSCs would allow to make them a potential tool for alternative therapies of SUI.

Can magnetic resonance imaging differentiate among transurethral bulking agent, urethral diverticulum, and periurethral cyst?

PURPOSE

To evaluate magnetic resonance imaging findings that differentiate among periurethral bulking agents (primarily collagen), urethral diverticulum, and periurethral cyst.

METHODS

We searched our radiologic database retrospectively from 2001 to 2017 for periurethral cystic lesions, identifying a total of 50 patients with 68 lesions. Final diagnoses in 68 lesions were bulking agents (27), urethral diverticula (29), and periurethral cysts (12). Two abdominal radiologists, blinded to clinical history, independently evaluated T1, T2, and post-contrast images. The readers assessed number, morphological features, location, connection to urethra and mass effect, signal intensity, and enhancement for each lesion. Fisher exact test and logistic regression analysis were performed for each univariate significant feature. The operative and pathologic reports were the reference standard.

RESULTS

Magnetic resonance imaging features found more often in bulking agents versus urethral diverticulum were multiple lesions (P = 0.011), upper or upper-mid-urethral location (P ≤ 0.0001), lack of internal fluid/fluid level (P = 0.002), no urethral connection (P = 0.005), T1 isointensity, and T2 mild hyperintensity compared to muscles but lower T2 signal than urine (P < 0.0001). Most cases of urethral diverticula and periurethral cysts were detected at mid- and lower urethra. Urethral diverticula were larger than bulking agents and periurethral cysts (P = 0.005 and P = 0.023) (mean diameter = 24, 16, 15 mm, respectively). Most bulking agents (93%) and urethral diverticula (90%) showed mass effect on urethra, while periurethral cysts (75%) did not (P < 0.0001).

CONCLUSION

Signal intensity and lesion characterization on magnetic resonance imaging can significantly differentiate bulking agent from urethral diverticulum and periurethral cyst. Radiologists should consider differential diagnosis of a bulking agent, especially when distinguishing characteristics described here are present to prevent incorrect diagnosis and ultimately unnecessary surgical intervention.

Medical Applications of Collagen and Collagen-Based Materials

Collagen and collagen-based materials have been successfully used in medicine for over 50 years. The number of scientific articles about the role of collagen in the construction of scaffolds for tissue engineering has risen precipitously in recent years. The review contains materials about historic and modern applications of collagen in medicine such as soluble collagen injections, solid constructs reconstructed from solution, and decellularized collagen matrices. The analysis of published data proves the efficacy of collagen material in the treatment of chronic wounds, burns, venous and diabetic ulcers, in plastic, reconstructive and general surgery, urology, proctology, gynecology, ophthalmology, otolaryngology, neurosurgery, dentistry, cardiovascular and bone and cartilage surgery, as well as in cosmetology. Further development of collagenoplasty requires addressing the problems of allergic complications, improvement of structure and maximizing therapeutic effects against pathological processes.

Complications of urethral bulking therapy for female stress urinary incontinence

AIMS

To review, report, and discuss the complications associated with urethral bulking therapy in female stress urinary incontinence.

METHODS

An extensive nonsystematic literature review on complications associated with injectable bulking agents used in the clinical practice was conducted. We reviewed articles published in English and indexed in the PubMed, Embase, and Google Scholar databases. Original articles, case reports, and case series were taken into consideration. Data regarding the safety of injectable bulking agents and the complications associated with their utility within the context of urethral bulking therapy for female stress urinary incontinence were extracted and discussed.

RESULTS

Approximately, 1/3 of the patients experience some type of a complication after urethral bulking therapy. The majority of these complications are of low grade, transient, do not necessitate additional surgical intervention, and amenable to treatment with conservative measures such as clean intermittent catheterization and antibiotics. However, more serious complications such as abscess formation, delayed hypersensitivity reactions, and vaginal erosion have been reported. Some of the injectable bulking agents have been withdrawn from the market because of their unfavorable adverse effect profile.

CONCLUSIONS

Urethral bulking therapy can be considered as a low-risk procedure. However, it is not without complications which can be severe in rare instances. The search for the ideal urethral bulking agent is ongoing and future comparative studies assessing the safety and efficacy of these compounds in randomized controlled settings are warranted.

Complications of Urethral Bulking Agents for Stress Urinary Incontinence: An Extensive Review Including Case Reports

OBJECTIVES

Stress urinary incontinence in women is a common problem that significantly impacts quality of life. Periurethral injection of urethral bulking agents (UBAs) is a simple, noninvasive, and cost-effective treatment. However, complications associated with UBA are often underappreciated. Objective of this review was to get a complete overview of all published complications of UBA.

METHODS

An extensive search of the scientific literature was conducted to quantitatively summarize the complications and their treatments of 8 UBAs. A total of 117 articles (original articles and case reports) were included in the final analysis. Complication incidence, treatment incidence, and follow-up time were extracted when mentioned. Statistical analysis of complication incidence of each UBA was calculated if possible.

RESULTS

A total of 2095 complications in 6462 treated patients were reported in 79 studies. Sixty-seven (3%) were considered serious implying operative correction (Clavien grade III); of these, 46 (69%) required incision and drainage, and 21 (31%) required a more invasive procedure. In 38 case reports and small case series, 49 patients were treated for 110 complications. Of these 110 complications, 41 (37%) can be classified as Clavien grade III.

CONCLUSIONS

This extensive review shows that various UBAs have different complication rates, with certain UBAs being more prone to serious complications. Based on available publications, most UBAs have a good safety profile, with low complication rates. However, although the majority of UBA complications are transient and require no or noninvasive treatment, serious complications may require invasive intervention and treatment.

Contemporary diagnostics and treatment options for female stress urinary incontinence

Stress urinary incontinence is not a deadly disease, but for the large population of women suffering from it, it is a very important issue. Especially in the continuously aging population all over the world, there is more and more need for treatment of this serious medical condition. Treatment of female stress urinary incontinence exists already for ages. In the 20th century invasive treatments like Burch colposuspension and pubovaginal slings were the mainstay of surgical treatments. The introduction of the midurethral sling made the procedure less invasive and accessible for more caregivers. Luckily there are many options available and the field is developing quickly. In recent years many new medical devices have been developed, that increase the number of treatment options available and make it possible to find a suitable solution for the individual patient based on subjective and objective results and the chances of complications. This manuscript provides an introduction to the therapeutical options that are available nowadays for female stress urinary incontinence.

Microfluidic production of bioactive fibrin micro-beads embedded in crosslinked collagen used as an injectable bulking agent for urinary incontinence treatment

Endoscopic injection of bulking agents has been widely used to treat urinary incontinence, often due to urethral sphincter complex insufficiency. The aim of the study was to develop a novel injectable bioactive collagen-fibrin bulking agent restoring long-term continence by functional muscle tissue regeneration. Fibrin micro-beads were engineered using a droplet microfluidic system. They had an average diameter of 140 μm and recombinant fibrin-binding insulin-like growth factor-1 (α₂PI_1-8-MMP-IGF-1) was covalently conjugated to the beads. A plasmin fibrin degradation assay showed that 72.5% of the initial amount of α₂PI_1-8-MMP-IGF-1 loaded into the micro-beads was retained within the fibrin micro-beads. In vitro, the growth factor modified fibrin micro-beads enhanced cell attachment and the migration of human urinary tract smooth muscle cells, however, no change of the cellular metabolic activity was seen. These bioactive micro-beads were mixed with genipin-crosslinked homogenized collagen, acting as a carrier. The collagen concentration, the degree of crosslinking, and the mechanical behavior of this bioactive collagen-fibrin injectable were comparable to reference samples. This novel injectable showed no burst release of the growth factor, had a positive effect on cell behavior and may therefore induce smooth muscle regeneration in vivo, necessary for the functional treatment of stress and other urinary incontinences.

STATEMENT OF SIGNIFICANCE

Urinary incontinence is involuntary urine leakage, resulting from a deficient function of the sphincter muscle complex. Yet there is no functional cure for this devastating condition using current treatment options. Applied physical and surgical therapies have limited success. In this study, a novel bioactive injectable bulking agent, triggering new muscle regeneration at the injection site, has been evaluated. This injectable consists of cross-linked collagen and fibrin micro-beads, functionalized with bound insulin-like growth factor-1 (α₂PI_1-8-MMP-IGF-1). These bioactive fibrin micro-beads induced human smooth muscle cell migration in vitro. Thus, this injectable bulking agent is apt to be a good candidate for regeneration of urethral sphincter muscle, ensuring a long-lasting treatment for urinary incontinence.

Safety and feasibility of platelet rich fibrin matrix injections for treatment of common urologic conditions

Purpose

Autologous platelet rich plasma (PRP) is used increasingly in a variety of settings. PRP injections have been used for decades to improve angiogenesis and wound healing. They have also been offered commercially in urology with little to no data on safety or efficacy. PRP could theoretically improve multiple urologic conditions, such as erectile dysfunction (ED), Peyronie's disease (PD), and stress urinary incontinence (SUI). A concern with PRP, however, is early washout, a situation potentially avoided by conversion to platelet rich fibrin matrix (PRFM). Before clinical trials can be performed, safety analysis is desirable. We reviewed an initial series of patients receiving PRFM for urologic pathology to assess safety and feasibility.

Materials and Methods

Data were reviewed for patients treated with PRFM at our center from November 2012 to July 2017. Patients were observed immediately post-injection and at follow-up for complications and tolerability. Where applicable, International Index of Erectile Function (IIEF-5) scores were reviewed before and after injections for ED and/or PD. Pad use data was collected pre/post injection for SUI.

Results

Seventeen patients were identified, with a mean receipt of 2.1 injections per patient. Post-procedural minor adverse events were seen in 3 men, consisting of mild pain at injection site and mild penile bruising. No patients experienced complications at follow-up. No decline was observed in men completing pre/post IIEF-5 evaluations.

Conclusions

PRFM appears to be a safe and feasible treatment modality in patients with urologic disease. Further placebo-controlled trials are warranted.

Stress urinary incontinence in women: Current and emerging therapeutic options

Surgical management of stress urinary incontinence (SUI) is most commonly achieved by midurethral synthetic sling (MUS) insertion as a first-line surgical option. A great deal of research continues to evolve new management strategies to reach an optimal balance of high efficacy and minimal adverse events. This expert opinion review provides a brief and comprehensive discussion of recent advances and ongoing research in the management of SUI, with an emphasis on single-incision mini-slings, vaginal laser treatment, and cell-based therapy. It is based on data obtained from numerous published meta-analyses and original studies identified through literature search. Single-incision mini-slings appear equally effective initially compared with standard MUS (retropubic or transobturator) for the treatment of female SUI; however, this efficacy lacks durability evidence beyond one-year followup. There is a lack of sufficient clinical evidence to currently confirm long-term safety and effectiveness of cell-therapy and non-ablative vaginal laser therapy, besides suggestion of apparent initial safety. There are still significant challenges to overcome before widespread clinical practice of the latter two modalities. Future research should be aimed at identifying groups of patients who might benefit from these minimally invasive therapeutic options.

Treatment of Stress Urinary Incontinence in Neurological Patients With an Injectable Elastomer Prosthesis: Preliminary Results

Many treatment options for stress urinary incontinence are difficult to apply to neurological patients. Urolastic is a new agent that is primarily indicated for women with mild stress urinary incontinence or men after prostate surgery. In this report, we present a series of 5 cases describing the first use of Urolastic to treat neurological patients. All patients were evaluated with a voiding diary and the use of auxiliary devices as the main indicators of continence. The median operative time was 30.8 minutes, and no complications were observed. Of the 5 patients, 4 reported improved incontinence: 2 switched from diapers to small pads, while the other 2 patients were able to discontinue urinary condom use. The only instance of treatment failure occurred in a patient with a low-compliance bladder. The advantages of this procedure appear to include a soft-cuff effect, reversibility, and minimal invasiveness. However, a future randomized study would be necessary to validate this treatment option.

Para-Urethral Injections with Urolastic® for Treatment of Female Stress Urinary Incontinence: Subjective Improvement and Safety

INTRODUCTION

Female stress urinary incontinence (SUI) is often treated surgically. Urethral bulking agents are a minimally invasive alternative, especially in patients suffering from intrinsic sphincter deficiency, but often with limited long-term efficacy. Urolastic® is a non-deformable, non-resorbable silicone elastomer that is used as an injectable. Its properties might result in a more durable response after injection. If this durability factor can be combined with a low complication rate, this can become a useful treatment option. We therefore assessed the subjective improvement and safety after treatment with Urolastic®.

MATERIALS AND METHODS

In 2 Dutch hospitals, 65 patients were treated with Urolastic®. The subjective improvement was assessed and the medical charts were reviewed for complications that appeared during the follow-up period. The complications were classified using the Clavien-Dindo classification.

RESULTS

We found that 76-88% of the patients showed subjective improvement at 12-25 months follow-up. The rate of improvement experienced was 50-70%. The rate of complications classified as Clavien-Dindo >II was 24-33%. The 12 patients with 75-100% subjective improvement after 2 months, showed 85% improvement after a median of 25 months.

CONCLUSIONS

With careful patient selection, Urolastic® seems to be a safe, durable and effective treatment option for female SUI.

Two Cases of Suspected Rejection of Polydimethylsiloxane Urethral Bulking Agent

We report the cases of 2 women who had urethral bulking injections with polydimethylsiloxane for stress urinary incontinence with intrinsic sphincter deficiency and reported initial improvement of symptoms followed by rapid return of stress urinary incontinence several weeks later associated with extrusion of the bulking material. We hypothesize this unique adverse outcome could represent immune rejection of this urethral bulking agent.

Effects of laser procedure for female urodynamic stress incontinence on pad weight, urodynamics, and sexual function

INTRODUCTION AND HYPOTHESIS

The impact of the IncontiLase^TM procedure on lower urinary tract symptoms (LUTS) remains unclear. Our aim was to evaluate the effects of the IncontiLase^TM procedure for urodynamic stress incontinence (USI).

METHODS

All consecutive women with USI prospectively underwent the IncontiLase^TM procedure. Urodynamic studies, pad testing, LUTS, and sexual function questionnaires were assessed before and after treatment.

RESULTS

Thirty-five women underwent the IncontiLase^TM procedure. Among the 28 women with baseline pad weights >1 g, 11 (39.3 %) were objectively cured and 11 (39.3 %) improved. Among the 18 women with mild USI (i.e., baseline pad weight 1-10 g), nine (50 %) were cured and five (27.8 %) improved. Among ten women with baseline pad weight >10 g, two (20 %) were cured and six (60 %) improved. Among the 32 women with complete questionnaire data at 6 months, seven (21.9 %) were subjectively cured, and four (12.5 %) improved. Regarding LUTS, the majority of domains on the King's Health Questionnaire and female sexual desire and function exhibited significant improvements. Forty percent (12/30) of the partners of these patients felt their sexual function had improved at 6 months. Nonetheless, urodynamic values did not differ across the timeline.

CONCLUSIONS

The effect of the IncontiLase^TM procedure for mild USI was moderate at 6-month follow-up but was not effective for pad weight >10 g. Moreover, it improved LUTS, quality of life, QoL, and sexual function of both partners. Further studies should be performed to assess long-term sustained efficacy.

Cross-sectional imaging following surgical interventions for stress urinary incontinence in females

Stress urinary incontinence (SUI) is a condition in which the weakness of the pelvic floor muscles causes unintentional loss of urine. For patients who are unable to achieve symptomatic improvement from lifestyle modification and pharmacotherapy, surgical placement of the pelvic slings or the use of urethral bulking agents has been shown to provide tremendous symptomatic improvement. Learning to recognize the pelvic slings and to identify their complications on imaging is invaluable; however, this is challenging because of the change in the local anatomy after surgical placement of the sling. In this paper, we present CT and MR imaging to demonstrate the surgical and non-surgical treatments of female SUI and their complications. Through this pictorial essay, our goal is to familiarize radiologists with recognizing the various forms of treatment for SUIs, the relevant pelvic anatomy, and complications that may occur secondary to the surgical placement of the pelvic slings.

Restoration of the pubourethral ligament with platelet rich plasma for the treatment of stress urinary incontinence

Stress urinary incontinence (SUI) is a major health problem, which affects nearly 20% of adult women and has a detrimental impact on their daily activities and quality of life. Several surgical techniques have been proposed for the treatment of SUI including the Burch colposuspension, retropubic mid-urethral slings (TVT), trans-obturator tapes (TOT), trans-obturator tapes inside out (TVT-O), bladder neck injections and the insertion of an artificial urethral sphincter. All of these treatments aim to either restore the urethral support, which is naturally preserved by the pubourethral ligament (PUL) or to increase the urethral resistance at rest. Most surgical techniques are associated with a variety of intraoperative and postoperative complications. Platelet rich plasma (PRP) is extremely rich in growth factors and cytokines, which regulate tissue reconstruction and has been studied extensively among trauma patients and trauma experimental models. To date, however, there is no evidence to support or oppose its use in women who suffer from SUI due to PUL damage. PRP is an easily produced and relatively inexpensive biologic material. It is produced directly from the patient's blood and is, thus, superior to synthetic materials in terms of potential adverse effects such as from foreign body reaction. In the present article we summarize the existing evidence in the field, which supports the conduct of animal experimental and clinical studies to elucidate the potential role of PRP in treating SUI.

The efficacy and safety of urethral injection therapy for urinary incontinence in women: a systematic review

To evaluate the efficacy and safety of different bulking agents for treating urinary incontinence in women, a systematic review including only randomized controlled trials was performed. The subjects were women with urinary incontinence. The primary outcomes were clinical and urodynamic parameters. The results were presented as a weighted mean difference for non-continuous variables and as relative risk for continuous variables, both with 95% confidence intervals. Initially, 942 studies were identified. However, only fourteen eligible trials fulfilled the prerequisites. Altogether, the review included 1814 patients in trials of eight different types of bulking agents, and all studies were described and analyzed. The measured outcomes were evaluated using a large variety of instruments. The most common complications of the bulking agents were urinary retention and urinary tract infection. Additionally, there were certain major complications, such as one case of death after use of autologous fat. However, the lack of adequate studies, the heterogeneous populations studied, the wide variety of materials used and the lack of long-term follow-up limit guidance of practice. To determine which substance is the most suitable, there is a need for more randomized clinical trials that compare existing bulking agents based on standardized clinical outcomes.

Translational approaches to the treatment of benign urologic conditions in elderly women

PURPOSE OF REVIEW

Stress urinary incontinence, overactive bladder, interstitial cystitis/painful bladder syndrome, and underactive bladder are highly prevalent among elderly women, and have significant impact on quality of life; however, existing treatments are limited and are not always successful for all patients. Researchers are investigating a multitude of new therapies to treat these conditions. This review will summarize the recent literature on investigative therapies for these conditions.

RECENT FINDINGS

Multiple new treatments are being developed for lower urinary tract dysfunction. Some of these treatments, including balloon therapy and muscle-derived stem cells for stress urinary incontinence, could provide alternatives to existing therapies. Others require further research before being used in patients, such as pudendal nerve stimulation for overactive bladder and intravesical liposomes for drug delivery in interstitial cystitis/painful bladder syndrome.

SUMMARY

Multiple new therapies are being investigated that could provide clinicians with additional tools to treat lower urinary tract disorders in millions of elderly women.

Targeted therapy for stress urinary incontinence: a systematic review based on clinical trials

INTRODUCTION

Controversy exists regarding the therapeutic benefit of cell-based therapy in the treatment of stress urinary incontinence (SUI).

AREAS COVERED

The aim of this systematic review was to evaluate evidence regarding the therapeutic effect and safety of cell-based therapy in the treatment of SUI and to propose a new approach to SUI treatment utilizing tissue engineering methodologies. We have thoroughly reviewed the literature using PubMed in order to identify only original, clinical studies involving cell therapy for SUI.

EXPERT OPINION

Cell-based therapy, as practiced today, is a safe but ineffective method for SUI treatment. The key to an optimal therapeutic outcome in SUI is accurate diagnosis combined with targeted therapy. Targeted therapy in SUI should be based on cell implantation to restore and regenerate the damaged urethral sphincter and/or the construction of a neo-pubourethral ligament utilizing tissue engineering methodologies.

Urolastic for the treatment of women with stress urinary incontinence: 24-month follow-up

Introduction

To evaluate the efficacy and durability of Urolastic, a new urethral bulking agent in women with stress urinary incontinence (SUI), after a follow-up of 24-months.

Material and methods

A follow-up study of women with SUI who received a Urolastic injection and successfully passed the 12-month follow-up. Assessment included the Stamey Grade, 1-h Pad weight test, and the International quality of life (I-QoL) score.

Results

Nineteen women who completed the 12-month follow-up were invited for the 24-month follow-up study. One patient did not respond to the correspondence. Four of the 18 patients who responded to the correspondence reported removal of the Urolastic implant at another facility, based on their desire. The explanation for this removal was painful intercourse (n = 1) or less than optimal dryness (n = 3). The overall objective improvement in continence status at 24-months was 66% compared to the 89% at the 12-month follow-up, while in addition the 1-h pad weight test showed >50% reduction in pad weight in 66% of patients compared to 84% at the 12-month follow-up. Adverse events reported were urinary tract infection (n = 1), local genital infection with erosion into the vagina (n = 1), painful intercourse (n = 2), and urgency (n = 4).

Conclusions

Urolastic is comparable to other bulking agents in terms of durability, efficacy, and complications.

[Intrinsic sphincter deficiency and female urinary incontinence]

OBJECTIVE

Stress urinary female incontinence (SUI) is primary due to intrinsic sphincter deficiency (ISD) and urethral hypermobility. Despite a lack of standardised international definition, ISD needs to be clearly diagnosed in order to be correctly treated. This work is an update about the female ISD produced from a review of a published article.

MATERIAL AND METHODS

This review of article published on this subject in the Medline (Pubmed database), selected according to their scientific relevants, of consensus conferences and published guidelines, has been performed by the committee for women pelvic floor surgery of the French Urological Association.

RESULTS

Although there is no international consensus definition, we can consider that the ISD is a composite concept combining urodynamic data (MUCP < 20 or 30 cmH20) and one or more clinical information (no urethral mobility, negative urethral support test, failure of a first surgery, leakage during abdominal straining, high stress incontinence scores). Imaging can provide additional evidence for intrinsic sphincter deficiency diagnosis, but the correlation between imaging and function remains low. By standardizing methodology and interpretations to better diagnose women with ISD, it may be possible to improve preoperative planning and outcomes for these patients. A retropubic midurethral sling can be performed as a first surgery. In case of a lack of urethral mobility, the artificial urinary sphincter (AUS) remains the gold standard. Adjustable continence therapy (ACT(®)) can be proposed as an alternative option. The efficacy and safety of muscle-derived cell therapy in ISD needs more studies. Injection of bulking agents may be an option according to the severity and the expectations of the patient. Bladder overactivity needs to be treated as first-line in case of mixed urinary incontinence. In elderly women, a careful evaluation of the bladder contractility and comorbidity must be performed. A geriatric evaluation can be necessary.

CONCLUSION

Clinical and paraclinical assessment allow to confirm the diagnosis of female ISD, to estimate its severity, and to identify associated mechanisms of incontinence (urethral hypermobility, bladder overactivity) to choose the most adapted treatment.

Urethral bulking agents versus other surgical procedures for the treatment of female stress urinary incontinence: a systematic review and meta-analysis

Bulking agents provide an alternative option in the management of women with stress urinary incontinence and they seem to have an important role in the management flow chart of SUI. However, evidence on this issue is scanty. The most important aspect is to understand whether bulking agents are comparable with the other first-line anti-incontinence surgical procedure (MUS, Burch colposuspension and pubovaginal slings). Hence, the primary aim of the current review was to assess the objective and subjective outcomes of bulking agents in comparison with the other surgical procedures for the treatment of SUI. PubMed and Medline were systematically searched and we included studies evaluating the use of bulking agents in comparison with other surgical approaches for either primary or recurrent treatment of female SUI. Three studies meeting the inclusion criteria were identified. Two of these studies were RCTs evaluating the use of bulking agents versus other surgical procedures for the treatment of primary female SUI; the remnant article was a retrospective cohort study that compared the effectiveness and safety of repeat midurethral sling with urethral bulking after failed midurethral sling. The combined results of all analyses showed that the objective recurrence rate of peri- or trans-urethral injections is significantly higher in comparison with the other surgical procedures. Similar findings were observed when considering separately the treatment for primary or recurrent SUI. Furthermore, lower subjective recurrence rate was observed among patients undergoing other surgical treatment in comparison with those undergoing bulking agents; however, this trend was not statistically significant. Moreover, patients undergoing injection of bulking agents experienced a lower rate of voiding dysfunctions in comparison to the control group. According to current evidence, bulking agents should not be proposed as first-line treatment in those women seeking permanent cure for both primary and recurrent SUI. However, the effectiveness of a procedure should be balanced with its invasiveness and patients' expectations. Bulking agents are a minimally invasive approach to treat SUI and their use should be considered as an alternative strategy particularly in special conditions: patients who are fragile, in those who do not wish to have surgery, or in whom surgical options are restricted (postoperatively, after irradiation).

Diagnosis and surgical treatment of stress urinary incontinence

Stress urinary incontinence (SUI) is a major problem affecting more than 20% of the nation's female population, with increasing prevalence as our population continues to age. Incontinence places a great burden on individuals, and the economic effect is large. Stress urinary incontinence occurs when there is involuntary leakage of urine during coughing, laughing, sneezing, or physical activity. It can be diagnosed during physical examination and by using low-cost office diagnostics. Although nonsurgical treatments provide some benefit, surgical interventions have demonstrated superiority with respect to subjective and objective cure and better long-term improvement. Corrective surgeries for SUI can be grouped into four categories: 1) slings (midurethral slings and slings placed at the ureterovesical junction), 2) retropubic urethropexy, 3) urethral bulking agents, and 4) artificial sphincters. The success and failure of each approach needs to be assessed in the context of individual patients and their circumstances. Slings and retropubic urethropexy are considered first-line surgical options. Since the advent of minimally invasive retropubic midurethral slings such as the tension-free vaginal tape, transobturator tension-free vaginal tape, and single-incision sling, retropubic urethropexy have fallen out of favor. Warnings about mesh use may contribute to a resurgence of retropubic urethropexy procedures such as the Burch procedure. A Burch procedure should still be considered for patients who have an aversion to mesh or if they are undergoing concurrent abdominal approach surgery. Urethral bulking agents are usually reserved for patients with a fixed, nonmobile urethra who cannot tolerate an operative experience or have failed previous antiincontinence procedures. Artificial sphincters should be considered an operation of last resort.

Dual growth factor-loaded in situ gel-forming bulking agent: passive and bioactive effects for the treatment of urinary incontinence

Stress urinary incontinence (SUI) is one of the major medical problems for adult females and has a devastating effect on their quality of life. The major cause of the development of the SUI is dysfunction of the urethral supporting tissues as a result of aging and childbirth. In this study, in situ gel-forming bulking agent loaded with dual growth factors, nerve growth factor (NGF) and basic fibroblast growth factor (bFGF), was fabricated. The bulking agent consisted of three components; (i) polycaprolactone (PCL) beads, (ii) bFGF-loaded nanogels, and (iii) NGF-loaded in situ gel forming solution. The bulking agent can provide an initial passive bulking effect (from the PCL beads) and regenerate malfunctioning tissues around the urethra (from the sequential and continuous release of growth factors from the hydrogel) for the effective treatment of SUI. The PCL beads were located stably at the applied urethra site (urinary incontinent SD rat) without migration to provide a passive bulking effect. The sequential release of the growth factors (NGF within a week and bFGF for more than 4 weeks) from the bulking agent provided regeneration of damaged nerve and smooth muscle, and thus enhanced biological function around the urethra. From the findings, we suggest that dual growth factor (NGF and bFGF)-loaded in situ gel-forming bulking agent may be a promising injectable bioactive system for the treatment for SUI.

A cost-effectiveness analysis of conservative versus surgical management for the initial treatment of stress urinary incontinence

OBJECTIVE

We sought to determine whether conservative or surgical therapy is more cost effective for the initial treatment of stress urinary incontinence (SUI).

STUDY DESIGN

We created a decision tree model to compare costs and cost effectiveness of 3 strategies for the initial treatment of SUI: (1) continence pessary, (2) pelvic floor muscle therapy (PFMT), and (3) midurethral sling (MUS). We identified probabilities of SUI after 12 months of use of a pessary, PFMT, or MUS using published data. Parameter estimates included Health Utility Indices of no incontinence (.93) and persistent incontinence (0.7) after treatment. Morbidities associated with MUS included mesh erosion, retention, de novo urge incontinence, and recurrent SUI. Cost data were derived from Medicare in 2012 US dollars. One- and 2-way sensitivity analysis was used to examine the effect of varying rates of pursuing surgery if conservative management failed and rates of SUI cure with pessaries and PFMT. The primary outcome was an incremental cost-effectiveness ratio threshold <$50,000.

RESULTS

Compared to PFMT, initial treatment of SUI with MUS was the more cost-effective strategy with an incremental cost-effectiveness ratio of $32,132/quality-adjusted life year. Initial treatment with PFMT was also acceptable as long as subjective cure was >35%. In 3-way sensitivity analysis, subjective cure would need to be >40.5% for PFMT and 43.5% for a continence pessary for the MUS scenario to not be the preferred strategy.

CONCLUSION

At 1 year, MUS is more cost effective than a continence pessary or PFMT for the initial treatment for SUI.

Efficacy and safety of polyacrylamide hydrogel for the treatment of female stress incontinence: a randomized, prospective, multicenter North American study

PURPOSE

Bulkamid® is a new polyacrylamide hydrogel bulking agent for stress urinary incontinence that is injected in the urethral submucosa using a specifically designed device. We evaluated the safety and efficacy of Bulkamid vs Contigen® collagen gel for stress urinary incontinence or stress predominant mixed urinary incontinence.

MATERIALS AND METHODS

This was a single-blind, randomized, prospective, 33-center, 2-arm parallel study of hydrogel vs collagen gel with followup to 1 year. At baseline patients underwent physical examination and bladder testing, and completed quality of life questionnaires and bladder diaries. After randomization patients could receive up to 3 injections at 1-month intervals. Patients were assessed 3, 6, 9 and 12 months after bulking. They completed bladder diaries and quality of life questionnaires, and pad weight was tested. At the last visit Valsalva leak point pressure was measured. Subjective and objective incontinence outcomes and adverse events were compared.

RESULTS

Of the 345 women 229 were randomized to hydrogel and 116 were randomized to collagen gel. At 12 months a 50% or greater decrease in leakage and incontinence episodes was seen in 53.2% and 55.4% of patients who received hydrogel and collagen gel, respectively. At 12 months 47.2% of patients with hydrogel and 50% with collagen gel reported zero stress incontinence episodes, and 77.1% and 70%, respectively, considered themselves cured or improved. Major adverse events were rare in each group.

CONCLUSIONS

Bulkamid is not inferior to Contigen. It has a favorable, persistent effect on stress urinary incontinence with a low risk of serious adverse events. Bulkamid is a new, simple, office based bulking system that shows promise as a treatment in women with stress urinary incontinence, particularly since Contigen is no longer commercially available.

Three-dimensional endovaginal sonography of synthetic implanted materials in the female pelvic floor

The objective of this pictorial essay is to emphasize the ability of 3-dimensional endovaginal sonography to image synthetic implanted materials in the female pelvic floor. Implanted materials discussed in this pictorial essay include polypropylene vaginal mesh, polypropylene suburethral slings, and urethral bulking agents. Three-dimensional endovaginal sonography allows for more detailed imaging compared to computed tomography and magnetic resonance imaging of the female pelvic floor, in that each plane can be manipulated to show unique images of synthetic implanted materials.

Urolastic-a new bulking agent for the treatment of women with stress urinary incontinence: outcome of 12 months follow up

Objective. To evaluate the efficacy and safety of the new injectable implant, Urolastic, in women with stress urinary incontinence (SUI) after 12-month followup. Materials and Methods. A prospective, cohort study included adult women with SUI. Patients were treated with Urolastic periurethral injections under local anaesthesia. The injection procedure was repeated after 6 weeks when indicated. Patients were evaluated for efficacy and safety parameters 6 weeks, 3 months, and 12 months after therapy. Results. Twenty women 56 (33-71) years old were included. Thirteen patients (65%) received one injection each (overall average of 2,1 mL); 7 patients (35%) received a second injection. Nineteen patients complete the 12-month followup. The mean Stamey incontinence grade significantly decreased from 1.9 at baseline to 0.4 at 12 months (visit IV) (P < 0.001). None of the patients were dry at baseline; 68% of them were dry at 12 months. The mean number of incontinence episodes significantly decreased from 6/day at baseline to 1.6/day at visit IV (P < 0.001). Reduction in pad weight went from 20.2 to 7.8 g at one year. The mean I-QoL score significantly increased from 51 at baseline to 76 at visit IV (P < 0.001). Six patients (30%) developed minor complications related to the injection procedure. Conclusions. Urolastic is effective and long-standing urethral bulking agent with moderate adverse events.

Tissue engineered bulking agent with adipose-derived stem cells and silk fibroin microspheres for the treatment of intrinsic urethral sphincter deficiency

In this study we developed a tissue engineered bulking agent that consisted of adipose-derived stem cells (ADSCs) and silk fibroin microspheres to treat stress urinary incontinence caused by severe intrinsic sphincter deficiency (ISD). ISD models were established by completely transection of the bilateral pudendal nerve (PNT) and confirmed by the decreased leak-point pressure (LPP) and increased lumen area of urethra. Injection of silk fibroin microspheres could recover LPP and lumen area at 4 weeks but its efficacy disappears at 8, 12 weeks. Moreover, it was exciting to find that tissue engineered bulking agent brought long-term efficacy (at 4, 8, 12 weeks post-injection) on the recovery of LPP and lumen area. Concomitantly with the function, tissue engineered bulking agent treated group also improved the urethral sphincter structure as exhibited by better tissue regeneration. The findings showed that silk fibroin microspheres alone could work effectively in short-term, while tissue engineered bulking agent that combined silk fibroin microspheres with ADSCs exhibited promising long-term efficacy. This study developed a new strategy of tissue engineered bulking agent for future ISD therapy.

Infusion therapy and implantables for the urologist

The specialty of urology has historically adapted to the changing health care environment. Urologists have been quick to adopt new technology, new therapeutics, and devices to render state-of-the-art patient care with improved clinical outcomes. The busy urology practice is now in the position to deliver many novel and unique therapies across multiple disease states. As a result, clinicians can provide state-of-the-art care in a clinic setting and potentially reduce the overall costs of health care delivery. This article reviews some of these potential new opportunities available to the practicing urologist.

Imaging of Urethral Bulking Agents

Urethral bulking is an office procedure for treatment of stress urinary incontinence that has increased in popularity in recent years. Numerous types of urethral bulking agents have been used since its introduction in the 1930s. Typically, these agents are imaged using specialty 3D 360° field-of-view transducers; however, a sonographer, during a pelvic or renal examination, may inadvertently find and image an echogenic structure near the urethrovesical junction in patients with a history of urethral bulking. Familiarizing oneself with the sonographic appearance of urethral bulking agents and optimizing techniques to obtain improved images of these agents may eliminate the need for additional imaging for the patient. Urethral bulking can be readily imaged with transducers commonly found in most ultrasound departments. This review will focus on the sonographic characteristics of urethral bulking agents and knowing when and how to use appropriate transducers to image the urethra.