Long-term effect of urethral dilatation and internal urethrotomy for urethral strictures

Effect of uncultured adipose-derived stromal vascular fraction on preventing urethral stricture formation in rats

Urethral stricture (US) remains a challenging disease without effective treatment options due to the high recurrence rate. This study aims to evaluate the preventive effect of uncultured adipose derived stromal vascular fraction (SVF) on urethral fibrosis in a rat model of US. Results demonstrated that US rats displayed hyperechogenic urethral wall with a narrowed lumen compared with sham rats, while SVF rats exhibited less extensive urethral changes. By histology, US rats showed obvious submucosal fibrosis in the urethral specimens, while SVF rats exhibited mild submucosal fibrosis with less extensive tissue changes. Furthermore, US rats showed increased gene and protein expression of collagen I (2.0 ± 0.2, 2.2 ± 0.2, all were normalized against GAPDH, including the following), collagen III (2.5 ± 0.3, 1.2 ± 0.1), and TGFβ1R (2.8 ± 0.3, 1.9 ± 0.2), while SVF cells administration contributed to decreased gene and protein expression of collagen I (1.6 ± 0.2, 1.6 ± 0.2), collagen III (1.8 ± 0.4, 0.9 ± 0.1), and TGFβ1R (1.8 ± 0.3, 1.3 ± 0.2), in parallel with the improvement of vascularization and increased expression of VEGF (1.7 ± 0.1) and bFGF (3.1 ± 0.3). Additionally, SVF served anti-inflammatory effect through regulation of inflammatory cytokines and cells, accompanied with conversion of the macrophage phenotype. Our findings suggested that uncultured SVF presented an inhibitory effect on stricture formation at an early stage of urethral fibrosis.

Endoscopic treatments prior to urethroplasty: trends in management of urethral stricture disease

BACKGROUND

To determine if the number of endoscopic treatments of urethral stricture disease (USD) prior to urethroplasty has changed in the context of new AUA guidelines on management of USD. In addition to an increase in practicing reconstructive urologists and published reconstructive literature, the AUA guidelines regarding the management of male USD were presented in May 2016, advocating consideration of urethroplasty in patients with 1 prior failed endoscopic treatment.

METHODS

A retrospective review of a prospectively maintained, multi-institutional urethral stricture database of high volume, geographically diverse institutions was performed from 2006 to 2017. We performed a review of relevant literature and evaluated pre-urethroplasty endoscopic treatment patterns prior to and after the AUA male stricture guideline.

RESULTS

2964 urethroplasties were reviewed in 10 institutions. There was both a decrease in the number of endoscopic treatments prior to urethroplasty in the pre-May 2016 compared to post-May 2016 cohorts both for overall urethroplasties (2.3 vs 1.6, P = 0.0012) and a gradual decrease in the number of pre-urethroplasty endoscopic treatments over the entire study period.

CONCLUSION

There was a decrease in the number of endoscopic treatments of USD prior to urethroplasty in the observed period of interest. Declining endoscopic USD management is not likely to be a reflection of a solely unique influence of the guidelines as endoscopic treatment decreased over the entire study period. Further research is needed to determine if there will be a continued trend in the declining use of endoscopic treatment and elucidate the barriers to earlier urethroplasty in patients with USD.

The effect of recurrent direct vision internal urethrotomy for short anterior urethral strictures on the disease course and the predictors of treatment failure

INTRODUCTION

The objective of this study was to investigate the disease course after direct vision internal urethrotomy (DVIU) for short anterior urethral strictures.

METHODS

We retrospectively analyzed 94 patients who underwent DVIU of the anterior urethra. Patients' age, etiology, length and localization of the strictures, total number of DVIU procedures, comorbidities, and other data were evaluated.

RESULTS

The mean age of the patients was 67.2 years. The mean followup duration was 27.1 months. Recurrence was observed in 27.6% of the patients. Recurrence had occurred in these patients at a mean of 12 months. Both the comorbidity score (rs=0.395; p<0.001) and the urinary tract infection (UTI) score (rs=0.492; p<0.001) had significant correlation with the recurrence. In patients with recurrent urethral stricture, as the number of DVIU increased, the length and number of the urethral stricture increased as well. Patients with recurrence had a single stricture in the first DVIU procedure, while the number of strictures increased to a mean of two in the second and/or third DVIU procedures.

CONCLUSION

DVIU is an effective treatment method in short anterior urethral stricture if it has been applied as a first intervention. However, if the stricture recurs, repeated DVIU application appears to be a negative predictive factor. The presence of perioperative treated UTI, smoking, and total number of comorbidities were negative predictive factors for the recurrence of urethral stricture. The disadvantages of our study is that it is retrospective, it includes a low number of patients, and the followup period is short.

Characteristics of the urethroplasty and our approach-Experience in patients with urethral stricture

OBJECTIVE

Urethral stricture is a common pathology with different etiologic factors in different age groups and societies. In our research, patients who underwent urethroplasty because of urethral stricture were evaluated in terms of etiology, localization, surgical technique and demographic characteristics.

MATERIAL AND METHODS

One hundred and sixty-three patients with a mean age of 53.43±16.5 years, operated between January 2008 and May 2016 because of urethral stricture were retrospectively included in the study. Diagnosis of the urethral stricture was established based on the complaints of the patient, results of urinalysis, urine culture, uroflowmetry, retrograde urethrography and/or voiding urethrography, and urethroscopy in case of need. Postoperative success for the patients was determined based on urinary flow rate and maximum flow rate of over 15 mL/sec were evaluated as success.

RESULTS

Etiologic factors for urethral stricture included trauma in 40 (24.5%), urethral catheterization in 45 (27.6%), endoscopic procedure in 59 (36.2%), infection in 10 (6.2%), idiopathic etiologies in 9 (5.5%) out of 163 patients. Mean length of the stricture was 3.6±1.7 cm. While the indicated number of patients had buccal mucosa graft (n=73, 44.7%), penile skin flap (n=21, 12.8%), Heineke-Mikulicz repair (n=5, 3.0%), and end-to-end anastomosis (n=64, 39.1%). Mean follow-up period was 43.2±33.7 months. Buccal mucosa graft was applied as ventral (n=32, 43.8%), dorsal (n=22, 30.2%), and dorsolateral (n=14, 19.2%) onlay, and transventrally dorsal inlay (n=5, 6.8%) grafts. Average success rates were 83.5% (n=61/73) in buccal mucosa, 76.2% (n=16/21) in penile skin grafts; 85.9% (n=55/64) in end-to-end anastomosis and 80.0% (n=4/5) in Heineke-Mikulicz repair.

CONCLUSION

Our assumption is that urethroplasty procedures have satisfactory long-term results, regardless of the location and size of the stenosis. According to our clinical experience, deciding on the most appropriate surgical technique by assessing each patient individually in experienced centers will increase success rates.

Posterior urethral stenosis after prostate cancer treatment: contemporary options for definitive management

Posterior urethral stenosis (PUS) is an uncommon but challenging problem following prostate cancer therapy. A review of the recent literature on the prevalence of PUS and treatment modalities used in the last decade was performed. A summative narrative of current accepted techniques in management of PUS is presented, and supplement with our own experience and algorithms.

An Experimental Model of Anterior Urethral Stricture in Rabbits With Local Injections of Bleomycin

OBJECTIVE

To develop an experimental model of anterior urethral stricture in rabbits using a bleomycin (BLM) injection technique.

MATERIALS AND METHODS

Thirty adult male New Zealand rabbits were randomly divided into 4 groups. In group 1 (BLM group), BLM was injected into the urethral submucosal tissue every other day through a catheter for 6 weeks at the 3-, 6-, 9-, and 12-o'clock positions of the urethra in 12 rabbits. In group 2 (phosphate-buffered saline [PBS] group), PBS was injected instead of BLM in 6 rabbits. In group 3 (stricture control group), an 8 × 20 mm urethral defect was created in 6 rabbits. In group 4 (normal group), 6 normal rabbits were included. All rabbits in the PBS group and stricture control group, as well as 6 rabbits in the BLM group, were sacrificed at 6 weeks. The remaining 6 rabbits in the BLM group were sacrificed at 10 weeks. Urethrography was performed in all rabbits before sacrifice, and the urethra was harvested for histologic analysis.

RESULTS

All rabbits in the BLM group showed mild urethral stricture at 4 weeks and significant urethral stricture at 6 weeks, without spontaneous resolution of the stricture at 10 weeks. No urethral stricture was observed in the PBS group at 4 and 6 weeks. Histologic examination confirmed the presence of fibrosis in the BLM group without spontaneous improvement.

CONCLUSION

BLM injection can induce an experimental model of anterior urethral stricture in rabbits. This simple, highly efficient, reproducible method can be carried out in any laboratory.

[Meatal and glandular urethral strictures]

Distal urethral strictures comprise meatal or glandular stenoses and occur due to trauma, iatrogenic instrumentalization, infection, skin diseases such as lichen sclerosus or idiopathically. Given that 18% of anterior strictures (bulbar, penile, or glandular) are located in the very distal part, meatal/glandular stricture disease represents a non-negligible subgroup among all urethral strictures. The prevalence within Western industrialized countries is estimated to be approximately 0.6-0.9%, which translates into a total of 250,000 men being affected in Germany. Without any therapy, there is a severe risk of functional damage to the kidneys and the remaining urinary tract as well as significant reduction of quality of life. The therapeutic success of regaining sufficient micturition and a satisfying cosmetic result can only be obtained by means of surgical intervention. Besides dilatation and urethrotomy, preferably a single or multiple staged open urethroplasty with transplantation of autogenous genital or non-genital tissue can be performed. The choice of the appropriate surgical concept depends on stricture etiology, comorbidity status, and the patient's compliance. In case of histologically diagnosed lichen sclerosus, the use of genital skin should be avoided. To date, there are no universally accepted recommendations regarding the optimal use of substitution techniques. However, the use of oral mucosal tissue grafts seem to be the most promising, given low recurrence rates, and thus can be considered as the current gold standard.

High-pressure balloon dilation for male anterior urethral stricture: single-center experience

OBJECTIVES

We retrospectively reviewed the urethral stricture cases treated in our tertiary center, and assessed the safety and feasibility of the high-pressure balloon dilation (HPBD) technique for anterior urethral stricture.

METHODS

From January 2009 to December 2012, a total of 31 patients with anterior urethral strictures underwent HPBD at our center, while another 25 cases were treated by direct vision internal urethrotomy (DVIU). Patient demographics, stricture characteristics, surgical techniques, and operative outcomes were assessed and compared between the two groups. The Kaplan-Meier survival analysis was applied to evaluate the stricture-free rate for the two surgical techniques.

RESULTS

The operation time was much shorter for the HPBD procedure than for the DVIU ((13.19±2.68) min vs. (18.44±3.29) min, P<0.01). For the HPBD group, the major postoperative complications as urethral bleeding and urinary tract infection (UTI) were less frequently encountered than those in DVIU (urethral bleeding: 2/31 vs. 8/25, P=0.017; UTI: 1/31 vs. 6/25 P=0.037). The Kaplan-Meier survival analysis showed that there was no significant difference in stricture-free rate at 36 months between the two groups (P=0.21, hazard ratio (HR)=0.65, 95% confidence interval (CI): 0.34 to 1.26). However, there was a significantly higher stricture-free survival in the HPBD group at 12 months (P=0.02, HR=0.35, 95% CI: 0.14 to 0.87), which indicated that the stricture recurrence could be delayed by using the HPBD technique.

CONCLUSIONS

HPBD was effective and safe and it could be considered as an alternative treatment modality for anterior urethral stricture disease.

Direct visual internal urethrotomy: Is it a durable treatment option?

OBJECTIVE

To evaluate the long-term success rate of direct vision internal urethrotomy as a treatment for anterior urethral strictures.

MATERIALS AND METHODS

We retrospectively analyzed the results for patients who underwent internal urethrotomy from January 2009 to January 2014 for anterior urethral strictures. Patients were followed till January 2016. Patients with complicated urethral strictures with a history of previous urethroplasty, hypospadias repair, or previous radiation were excluded from the study, as anticipated low success rate of direct visual internal urethrotomy (DVIU) in these patients. The Kaplan-Meier method was used to analyze stricture-free probability after the first, second, and third urethrotomy.

RESULTS

A total of 186 patients were included in this study. Stricture-free rates after first, second, and third urethrotomy were 29.66%, 22.64%, and 13.33%, respectively.

CONCLUSIONS

Although DVIU may be a management option for anterior urethral stricture disease, it seems that long-term results are disappointing.

A preliminary clinical study of endoscopic minimally-invasive surgery in urethral stricture complicated with false passage

The aim of this study was to explore the clinical effect of endoscopic minimal invasive surgery on posterior urethral stricture with false passage. Twenty-one patients suffering from posterior urethral stricture with false passage were involved in the study. All the patients received pre-operative urethrography and flexible cystoscopy to make sure that the distance between the blind end of the proximal normal urethra and the distal urethra was <1 cm. Ten patients received open operation and eleven patients underwent endoscopic minimally-invasive surgery. All the patients in both groups had their catheters removed 4 weeks after operations, and improvements in urination and incontinence were observed. Urethrography was performed and urine flow rate was measured 1 month after catheter removal. In the open-operation group, nine patients showed unobstructed urinary tracts in the urethrography, and one, after his catheter removal, experienced dysuresia, which was improved after urethral dilatation. In the minimally-invasive operation group, nine patients showed patent urinary tracts in the urethrography, and two experienced post-operation dysuresia, of whom, open-operation treatment and urethral dilatation were performed respectively. In the minimally-invasive operation group, the average urine flow rate was significantly increased. Patients in both groups obtained obvious improvement in post-operation urinary incontinence, and there was no statistically significant difference between the two groups in urine flow rate and index for urinary incontinence. Endoscopic minimally-invasive operation had similar effects to open operation in treatment of posterior urethra stricture with <1 cm in length and false passage.

A randomized clinical trial comparing intracorpus spongiosum block versus intraurethral lignocaine in visual internal urethrotomy for short segment anterior urethral strictures

OBJECTIVES

The primary objective was to compare the effectiveness in pain relief of intracorpus spongiosum block (ICSB) versus intraurethral topical anesthesia (TA) using 2% lignocaine jelly for performing visual internal urethrotomy (VIU) for short segment anterior urethral strictures.

MATERIALS AND METHODS

It was a randomized, parallel group controlled trial. Participants are adult patients with a single anterior urethral stricture up to 2 cm in length. Patients were allocated to two intervention groups with thirty patients in each group. For anesthesia of the urethra, Group 1 patients received ICSB whereas Group 2 patients received intraurethral TA using 2% lignocaine jelly before VIU. Patient discomfort was assessed with visual analog scale (VAS) during the procedure and 1 h postprocedure. The increase in pulse rate and the change in systolic blood pressure (BP) during the procedure were recorded. The procedure was considered successful if there was absence of symptoms or signs of recurrent stricture and ability to pass freely 18Fr catheter during urethral calibration at last follow-up.

RESULTS

From March 2014 to June 2015, sixty patients were randomized into two groups of thirty patients each. The mean (±standard deviation) intraoperative VAS score was 2.8 ± 1.1 in Group 1, which was significantly less (P < 0.05) than the 5.6 ± 1.7 score in Group 2. The mean 1 h postoperative VAS score was also significantly lower in Group 1 patients (1.0 ± 1.0) than in Group 2 patients (3.2 ± 1.5). The change in pulse rate was significantly greater in Group 2 (21.3 ± 10.1 beats/min) than in Group 1 (10.6 ± 4.6 beats/min, P < 0.05). The change in systolic BP was also significantly higher in Group 2 (16.3 ± 8.6 mmHg) than in Group 1 (9.1 ± 4.4 mmHg, P < 0.05). The stricture-free rate at 6-month after VIU in Group 1 and Group 2 patients were 88.5% and 89.6%, respectively.

CONCLUSIONS

ICSB has better pain control with similar complication and recurrence rate than intraurethral lignocaine jelly alone in VIU.

Effect of adipose tissue-derived stem cell injection in a rat model of urethral fibrosis

INTRODUCTION

We sought to evaluate the therapeutic effect of adi-pose tissue-derived stem cells (ADSCs) in a rat model of urethral fibrosis.

METHODS

Eighteen (18) male Sprague-Dawley rats (300‒350 g) were divided into three groups: (1) sham (saline injection); (2) urethral fibrosis group (10 μg transforming growth factor beta 1 (TGF-β1) injection); and (3) ADSCs group (10 μg TGF-β1 injection plus 2 × 10⁵ ADSCs). Rat ADSCs were harvested from rat inguinal fat pads. All study animals were euthanized at two weeks after urethral injection. Following euthanasia, rat urethral tissue was harvested for histologic evaluation. Type I and III collagen levels were quantitated by Western blot analysis.

RESULTS

TGF-β1 injection induced significant urethral fibrosis and increased collagen type I and III expression (p<0.05). Significant decrease in submucosal fibrosis and collagen type I and III expression were noted in the ADSCs group compared with the urethral fibrosis group (p<0.05). TGF-β1 induced fibrotic changes were ameliorated by injection of ADSCs.

CONCLUSIONS

Local injection of ADSCs in a rat model of urethral fibrosis significantly decreased collagen type I and III. These findings suggest that ADSC injection may prevent scar formation and potentially serve as an adjunct treatment to increase the success rate of primary treatment for urethral stricture disease. Further animal and clinical studies are needed to confirm these results.

Distal urethroplasty for fossa navicularis and meatal strictures

Distal urethral strictures involving the fossa navicularis and meatus represent a unique subset of urethral strictures that are particularly challenging to reconstructive urologists. Management of distal urethral strictures must take into account not only maintenance of urethral patency but also glans cosmesis. A variety of therapeutic approaches exist for the management of distal urethral strictures, including dilation, meatotomy, extended meatotomy, flap urethroplasty, and substitution grafting. Common etiologies for distal urethral strictures include lichen sclerosus, instrumentation, and prior hypospadias repair. Proper patient selection is paramount to the ultimate success and durability of the treatment, which should be individualized and include an assessment of the stricture etiology, location, and burden, and patient-centered goals of care.

Visual Internal Urethrotomy for Adult Male Urethral Stricture Has Poor Long-Term Results

Objective. To determine the long-term stricture-free rate after visual internal urethrotomy following initial and follow-up urethrotomies. Methods. The records of all male patients who underwent direct visual internal urethrotomy for urethral stricture disease in our hospital between July 2004 and May 2012 were reviewed. The Kaplan-Meier method was used to analyze stricture-free probability after the first, second, third, fourth, and fifth urethrotomies. Results. A total of 301 patients were included. The overall stricture-free rate at the 36-month follow-up was 8.3% with a median time to recurrence of 10 months (95% CI of 9.5 to 10.5, range: 2–36). The stricture-free rate after one urethrotomy was 12.1% with a median time to recurrence of eight months (95% CI of 7.1–8.9). After the second urethrotomy, the stricture-free rate was 7.9% with a median time to recurrence of 10 months (95% CI of 9.3 to 10.6). After the third to fifth procedures, the stricture-free rate was 0%. There was no significant difference in the stricture-free rate between single and multiple procedures. Conclusion. The long-term stricture-free rate of visual internal urethrotomy is modest even after a single procedure.

Is there a way to predict failure after direct vision internal urethrotomy for single and short bulbar urethral strictures?

OBJECTIVE

To identify patient and stricture characteristics predicting failure after direct vision internal urethrotomy (DVIU) for single and short (<2 cm) bulbar urethral strictures.

PATIENTS AND METHODS

We retrospectively analysed the records of adult patients who underwent DVIU between January 2002 and 2013. The patients' demographics and stricture characteristics were analysed. The primary outcome was procedure failure, defined as the need for regular self-dilatation (RSD), redo DVIU or substitution urethroplasty. Predictors of failure were analysed.

RESULTS

In all, 430 adult patients with a mean (SD) age of 50 (15) years were included. The main causes of stricture were idiopathic followed by iatrogenic in 51.6% and 26.3% of patients, respectively. Most patients presented with obstructive lower urinary tract symptoms (68.9%) and strictures were proximal bulbar, i.e. just close to the external urethral sphincter, in 35.3%. The median (range) follow-up duration was 29 (3-132) months. In all, 250 (58.1%) patients did not require any further instrumentation, while RSD was maintained in 116 (27%) patients, including 28 (6.5%) who required a redo DVIU or urethroplasty. In 64 (6.5%) patients, a redo DVIU or urethroplasty was performed. On multivariate analysis, older age at presentation [odds ratio (OR) 1.017; P = 0.03], obesity (OR 1.664; P = 0.015), and idiopathic strictures (OR 3.107; P = 0.035) were independent predictors of failure after DVIU.

CONCLUSION

The failure rate after DVIU accounted for 41.8% of our present cohort with older age at presentation, obesity, and idiopathic strictures independent predictors of failure after DVIU. This information is important in counselling patients before surgery.

Collagenase Clostridium histolyticum (Xiaflex) for the Treatment of Urethral Stricture Disease in a Rat Model of Urethral Fibrosis

OBJECTIVE

To evaluate the treatment effect of collagenase Clostridium histolyticum (CCH) in a rat model of urethral fibrosis.

MATERIALS AND METHODS

Thirty male Sprague-Dawley rats (300-350 g) were divided into 5 groups. The rat urethra was injected with normal saline in the sham group and, in the other 4 groups, the rat urethra was injected with 10 μg of transforming growth factor beta 1 to create fibrosis of the urethra. Two weeks following transforming growth factor beta 1 injection, the rats were injected with varying doses of CCH or vehicles, depending on their group. The rats were then euthanized at 4 weeks after CCH or vehicle injection. Urethral tissue was harvested for histologic and molecular analyses. Type I and III collagen levels were evaluated by Western blot analysis.

RESULTS

There was urethral fibrosis and to significant increase in collagen type I and III expressions in the urethral fibrosis group compared with the sham group (P <.05). Urethral injection of CCH appeared to be safe and significantly reduce urethral fibrosis as well as collagen type I and III expressions in the high-dose CCH treatment groups when compared with the treatment control group (P <.01).

CONCLUSION

This study demonstrated a beneficial effect of CCH injections in a rat model of urethral fibrosis. These findings suggest a potential role for CCH as a therapeutic option in urethral stricture patients and warrant further investigation.

Erectile dysfunction in urethral stricture and pelvic fracture urethral injury patients: diagnosis, treatment, and outcomes

Urethral stricture disease, pelvic fracture urethral injury (PFUI), and their various treatment options are associated with erectile dysfunction (ED). The etiology of urethral stricture disease is multifactorial and includes trauma, inflammatory, and iatrogenic causes. Posterior urethral injuries are commonly associated with pelvic fractures. There is a spectrum in the severity of both conditions and this directly impacts the treatment options offered by the surgeon. Many published studies focus on the treatment outcomes and the relatively high recurrence rates after surgical repair. This communication reviews the current knowledge of the association between ED and urethral stricture disease, as well as PFUI. The incidence, pathophysiology, and clinical ramifications of both conditions on sexual function are discussed. The treatment options for ED in those patients are reviewed and summarized.

Outcome of urethral strictures treated by endoscopic urethrotomy and urethroplasty

INTRODUCTION

We analyze the outcomes of patients with urethral stricture who underwent surgical treatment within the past 5 years.

METHODS

This is a retrospective study of male patients who underwent surgery for urethral stricture at our service from January 2008 to June 2012. We analyzed the comorbidities, type, length and location of the stricture and the surgical treatment outcome after endoscopic urethrotomy, urethroplasty or both.

RESULTS

In total, 45 patients with a mean age of 53.7 ± 16.7 years underwent surgical treatment for urethral stricture. Six months after surgery, 46.7% of the patients had a maximum urinary flow greater than 15 mL/s, whereas 87.3% of the patients exhibited no stricture by urethrography after the treatment. The success rate in the patients undergoing urethrotomy was 47.8% versus 86.4% in those undergoing urethroplasty (p = 0.01). Twenty percent of the patients in whom the initial urethrotomy had failed subsequently underwent urethroplasty, thereby increasing the treatment success.

CONCLUSION

In most cases, the treatment of choice for urethral stricture should be urethroplasty. Previous treatment with urethrotomy does not appear to produce adverse effects that affect the outcome of a urethroplasty if urethrotomy failed, so urethrotomy may be indicated in patients with short strictures or in patients at high surgical risk.