The Use of Flaps and Grafts in the Treatment of Urethral Stricture Disease

Prospects and Challenges of Electrospun Cell and Drug Delivery Vehicles to Correct Urethral Stricture

Current therapeutic modalities to treat urethral strictures are associated with several challenges and shortcomings. Therefore, significant strides have been made to develop strategies with minimal side effects and the highest therapeutic potential. In this framework, electrospun scaffolds incorporated with various cells or bioactive agents have provided promising vistas to repair urethral defects. Due to the biomimetic nature of these constructs, they can efficiently mimic the native cells’ niches and provide essential microenvironmental cues for the safe transplantation of multiple cell types. Furthermore, these scaffolds are versatile platforms for delivering various drug molecules, growth factors, and nucleic acids. This review discusses the recent progress, applications, and challenges of electrospun scaffolds to deliver cells or bioactive agents during the urethral defect repair process. First, the current status of electrospinning in urethral tissue engineering is presented. Then, the principles of electrospinning in drug and cell delivery applications are reviewed. Finally, the recent preclinical studies are summarized and the current challenges are discussed.

Long-term outcomes for 2-stage urethroplasty: an analysis of risk factors for urethral stricture recurrence

Purpose

To report long-term results and patient reported outcomes of staged anterior urethroplasties, and isolate risk factors for recurrence.

Methods

 We reviewed urethroplasty database for all patients who underwent staged urethroplasty from 2000 to 2017. Follow-up included a cystoscopy 4 months after their 2nd stage to assess early success, and then annual follow-up thereafter with post-void residual and symptom assessment. Stricture characteristics, etiology and graft type were analyzed with regards to success.

Results

 Forty-nine patients were eligible for inclusion. The median stricture length was 7 cm (3–17 cm). The early success rate demonstrated by cystoscopy at 4 months was 100%. Long-term success was 96.4% in buccal graft (BMG) only patients; however, long-term success fell considerably to 53% in patients requiring any use split thickness skin graft (STSG) in the first stage. Median follow up time was 57 months (6–240 months). On analysis, age, increased stricture length and especially the use of STSG all appeared to be associated with late recurrence. The recurrence group had longer stricture length and were more likely to be panurethral. All recurrences occurred after the initial 4-month cystoscopy with a median time to recurrence of 78 months.

Conclusion

Staged repairs that are amenable to BMG-only repairs have high long-term success rates. Increasing stricture length and the addition of split-thickness skin graft were associated with lower success rate in staged urethral reconstruction. Patients requiring staged repairs often experience recurrence in a very delayed fashion reinforcing the need for close, long-term follow up.

Scar-modulating agents post urethroplasty: Could phosphodiesterase-5 inhibitors be the answer?

Background:

Phosphodiesterase enzyme inhibitors (PDEIs) are most commonly prescribed by urologists for the treatment of erectile dysfunction. They are also gaining popularity as a treatment for lower urinary tract symptoms, based on their effect on smooth muscles – either vascular smooth muscles or smooth muscles in the urinary tract. For vascular smooth muscles, they cause vasodilation, enhanced microcirculatory haemodynamics through inhibition of platelet aggregation and adhesion, induction of apoptosis of adhesion fibroblasts and a reduction in the scarring process.

Methodology:

We reviewed articles published in English and indexed in the PubMed, Embase and Google Scholar databases, and consulted textbooks. Key search terms used were: urethral stricture, anti-fibrotic, scar-modulating agent, PDEIs, urethral scarring and urethroplasty. We created a synopsis of relevant articles, including original research studies and reviews. Level of evidence: Not applicable.

Double-face Augmentation Urethroplasty for Bulbar Urethral Strictures: Technical Implications and Short-term Outcomes for a Dorsal Versus Ventral Approach

This study describes technical implications and compares short-term outcomes after a dorsal versus ventral approach for double-face augmentation urethroplasty (DFAU) for treating a near-obliterated bulbar urethral stricture (BUS). This was a retrospective evaluation of a prospectively collected database of patients with BUS (<2 cm) who underwent DFAU. The choice between the approaches depended on (1) landmark identification (the relation between the bulbospongiosus muscle and the distal end of the stricture) and (2) corpus spongiosum width. In DFAU, inlay augmentation was at the level of the narrowed urethral plate (<6 Fr). Patient follow-up data (symptom score and uroflowmetry) were assessed every 3 mo for the first year, and every 6 mo thereafter. A successful outcome was defined as a normal urinary flow rate without obstructive voiding symptoms. Fifty-two patients underwent DFAU for BUS (dorsal approach, n = 30; ventral approach, n = 22). The maximum flow rate and symptom scores significantly improved in both groups. The overall success rates (86%) were similar. In conclusion, a dorsal approach for DFAU is versatile and can be considered in all circumstances. A ventral approach should be performed in patients with proximal BUS. The short-term outcomes were similar for both approaches.

Patient summary

We assessed whether double-face augmentation urethroplasty is a suitable option for treating near-obliterated bulbar urethral strictures using two free grafts for augmentation to improve the urinary flow. This operation can be performed using two methods and both techniques were safe with similar short-term outcomes.

Analysis of the Determinants, Characteristics and Management of Recurrent Urethral Strictures

Background:

The presentation and management of the recurrent urethral stricture varies and depends largely on the initial treatment and the characteristics of the recurrent stricture. What are the likely determinants of recurrence?

Patients and Methods:

This is a retrospective review of all patients who had urethroplasties from January 2013 to December 2017 for anterior urethral strictures in our institution. Patients with a recurrence of the strictures were identified and reviewed, while patients with hypospadias and posterior urethral stenosis or contractures were excluded from the study. The etiology, length, site, and type of urethroplasties were evaluated as variables that may contribute to the recurrence of strictures using inferential statistics and logistic regression analysis. Time to recurrence was analyzed using the Kaplan–Meier method.

Results:

A total of 206 urethroplasties for anterior urethral strictures were evaluated with recurrence of strictures noted in 29 patients and a recurrence rate of 14.1%. Recurrence was higher in long-segment strictures, penobulbar strictures, and postinflammatory strictures. Pedicle flaps were used in 45% of the strictures that reoccurred. Using Chi-square, the length, site, of urethroplasties were statistically significant determinants of recurrence; however, only the site of stricture was found to be statistically significant following logistic regression analysis. The site of recurrence was in the bulbar urethra in 79% and the penile urethra in 21%. The choice of treatment of the recurrent strictures was anastomotic urethroplasty in 76.5%. The mean time to failure in this study was 13 months with a range of 6-120 months.

Conclusion:

In this study, the site of stricture was found to be the most determinant of stricture recurrence, with penobulbar strictures mostly implicated. Long-segment strictures were also noted to contribute to some extent in recurrence. These recurrent strictures were mostly short-segment strictures in the bulbar urethra which were amenable to excision and anastomosis to achieve cure.

Histopathological changes in oral mucosa in cases of failed augmented urethroplasty

OBJECTIVE

Histopathological changes in oral (buccal or lingual) mucosa after exposure to urine are still not completely understood. We evaluated these changes in free oral mucosal graft integrated in human urethra.

MATERIAL AND METHODS

Total 19 patients with recurrent urethral stricture after oral mucosa urethroplasty (buccal 12 and lingual 7) were prospectively evaluated. Intraoperatively integrated buccal or lingual mucosal graft sample that was previously engrafted to urethra was completely excised along with healthy oral mucosa, and it was sample processed for histopathological evaluation by dedicated pathologist. Preoperative clinical data were properly collected from all the study participants.

RESULTS

The mean age of the patients was 30 years, and the mean preoperative peak flow rate was 4.2 mL/s. Etiology of initial stricture was idiopathic in 13 (68.42%) patients and traumatic urethral catheterization in 6 (31.58%) patients. Mean interval from previous buccal mucosal urethroplasty to current urethroplasty was 21.9 months (range 12-46 months). On repeat urethroplasty, the mean stricture segment length was 59.2 (38-77) mm [60.08 (38-74.6) mm buccal, and 58.32 (39.6-77) mm lingual]. These integrated oral mucosal grafts maintained their histopathological characteristics in all patients except some kind of changes like submucosal fibrosis in seven (58.33%) cases of buccal and vacuolar degeneration in five (71.42%) cases of lingual mucosal urethroplasty.

CONCLUSION

Histopathological characteristics of integrated oral (buccal and lingual) mucosal grafts were maintained even on exposure to urine except some changes like submucosal fibrosis and vacuolar degeneration. Impact of these changes require further research.

Penile urethral stricture disease

Patients affected by a urethral stricture account for a considerable cost to all healthcare systems. The estimated prevalence of all urethral stricture in the UK is 10/100,000 men during youth, increasing to about 40/100,000 by age 65 years and to more than 100/100,000 thereafter. A penile urethral stricture is a narrowing of the lumen of the urethra due to ischaemic fibrosis of the urethral epithelium and/or spongiofibrosis of the corpus spongiosum occurring within the penile urethra. Its aetiology is largely idiopathic but other important causes are failed hypospadias repair and lichen sclerosus, which account for 60% of all cases. Strictures of the anterior urethra account for 92% of cases: bulbar strictures are more frequent (46.9%), followed by penile (30.5%) and combined bulbar/penile (9.9%), that is, 40.4% of all men presenting with stricture will have a penile urethral stricture alone or in combination with a bulbar urethral stricture. There are several options for the treatment of penile urethral strictures ranging from less invasive treatments, including urethral dilatation and direct vision internal urethrotomy, to more complex augmentation graft and flap urethroplasty. The aim of the present review is to describe the aetiology and epidemiology of anterior urethral strictures and the available options reported in literature for their treatment.

Level of evidence: 1a

Excision and Primary Anastomosis Reconstruction for Traumatic Strictures of the Pendulous Urethra

OBJECTIVES

To present a multi-institutional experience with functional and patient-reported outcomes among men undergoing excision and primary anastomosis (EPA) urethroplasty for pendulous urethral strictures.

METHODS

We describe the technique and present our experience with EPA for focal penile strictures. Patients undergoing urethroplasty (2004-2017) at 2 tertiary referral centers were reviewed, of whom 14 (0.7%) underwent EPA of radiographically confirmed pendulous urethral strictures. Validated questionnaires were utilized to evaluate overall improvement (Patient Global Impression of Improvement), urinary bother (International Prostate Symptom Score), and sexual function (International Index of Erectile Function-5). Treatment success was defined as urethral patency without need for subsequent reconstruction.

RESULTS

Among 14 men undergoing penile EPA, 13/14 (93%) had durable treatment success over a median follow-up of 43 months. No patient reported penile curvature postoperatively. Stricture etiology in most cases was posttraumatic (12/14), of which 4 had a history of urethral disruption secondary to penile fracture and 8 iatrogenic trauma. Median age was 51 years (IQR 30-60) and stricture length 1.0 cm (IQR 1.0-1.4). Erectile function was normal in 8/14 patients preoperatively, and postoperative median International Index of Erectile Function was 21. Most men reported significant global improvement in condition (median Patient Global Impression of Improvement 2, IQR 1-3) and most had only mild urinary bother (median International Prostate Symptom Score 4, quality of life 1). The single treatment failure had a history of hypospadias with multiple prior urethral procedures.

CONCLUSION

For men with short strictures of the pendulous urethra, EPA has a high success rate, without adverse sequelae such as erectile function or penile curvature.