Detailed surgical technique for endoscopic urethroplasty in the treatment of anastomotic stenosis and bladder neck contracture

Authors: Miriam E. Dash, J. Nicholas Warner

Abstract

Prostate procedures, including radical prostatectomies and transurethral outlet surgeries, are commonly performed in the U.S. with complications such as vesicourethral anastomotic stenosis (VUAS) and bladder neck contracture (BNC) affecting 2–12% of patients. Traditionally, patients with VUAS or BNC have been managed through recurrent dilations or resections, though success rates vary. Steroids and mitomycin C have shown some benefit, but refractory cases may require complex abdominoperineal repairs. Robotic surgeries have improved outcomes, with success rates ranging from 75% to 100%, albeit with the associated increased risks and limitations of intra-abdominal surgeries. In 2021, our group introduced the transurethral incision with transverse mucosal realignment (TUITMR) procedure, a technique that offers a similar approach to robotic urethroplasties by incising scar tissue and advancing healthy bladder mucosa. In a study of 19 patients evaluated within 1 year of surgical correction, TUITMR demonstrated an 89% success rate after one treatment and 100% after two, importantly, with no reported de novo incontinence. This paper highlights the preoperative preparation, surgical technique and postoperative considerations involved in TUITMR overall, as well as particulars related to VUAS and BNC patient populations specifically. The surgical technique is described in detail, along with tips and pearls for each group. Ultimately, we describe a minimally invasive surgical technique that utilizes healthy mucosal tissue to offer a long-lasting, and potentially permanent, solution to bladder neck complications following prostate surgery without the need for open or robotic surgical methods.

Introduction

Background

It is estimated that nearly 250,000 prostate procedures are performed annually in the United States, including prostatectomies for malignancy and transurethral surgery for benign prostatic hyperplasia (1,2). While techniques have improved, the rate of vesicourethral anastomotic stenosis (VUAS) after prostatectomy remains a known complication of the operation in 2–12% of patients (3,4). The rate goes up for patients with an additional history of pelvic radiation (5). Similarly, the rate for bladder neck contracture (BNC) after surgery for benign prostate enlargement has a similar range, independent of the type of outlet surgery (6-8).

Rationale

Historically, most patients were managed with recurrent dilations or resections with reported success rates of 20–80%, worse in refractory cases (9,10). To enhance the outcomes, some authors noted improvement with steroids or mitomycin C (11,12). In refractory cases, some patients go on to complex abdominoperineal repair (13). To minimize the morbidity and postoperative incontinence, robotic approaches have been described, including a Y-V plasty of the bladder neck (14-16) or T plasty (17). The robotic approaches are noted to offer a higher success rate, ranging from 75% to 100% (14-17). The objective of these robotic surgeries is to remove or incise scar tissue and advance healthy bladder mucosa across the defect.

Objective

In 2021, our group introduced the transurethral incision with transverse mucosal realignment (TUITMR) to accomplish a similar goal of opening the scar tissue and advancing the bladder neck across the defect (18). In 19 patients with both VUAS and BNC, with and without radiation, our success rate was noted to be 89% after one treatment. If a patient failed, they underwent a second TUITMR, and all patients were successful on the second attempt. Notably, no patient developed* de novo *incontinence. There was no perioperative change to the secondary surgery versus the primary surgery, and no notable differences intraoperatively. Herein, we will provide updates to the work-up and techniques of the operation. We present this article in accordance with the SUPER reporting checklist (available at https://tau.amegroups.com/article/view/10.21037/tau-2025-226/rc).

Preoperative preparations and requirements

Preliminary conditions

The reported surgical technique was consistently performed by a single surgeon at a quaternary academic hospital. Cases were performed within a sterile operating room with appropriate anesthesia and nursing staff available. This technique is not limited to specialized institutions and may be completed in any operating room with the appropriate sterile urologic equipment. Patient disease states and medical comorbidities are not a primary factor in eligibility. All patients cleared for endoscopic surgery are eligible to receive TUITMR. Specific surgical instruments required are cited for consistency. The surgical team included one attending urologist and one bedside assistant. The learning curve varied by the assistant’s prior endoscopic exposure. Operative time for TUITMR completion ranged from 30 to 45 minutes. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Mayo Clinic Institutional Review Board (IRB 18-012053). Individual consent for this retrospective analysis was waived.

BNC

Regarding the patient’s history, we like to know the date of prior prostate surgeries, prior BNC interventions, and any history of radiation therapy to the pelvis. We also prefer to determine if the patient experienced any incontinence after the previous interventions to help counsel them regarding potential incontinence after the TUITMR. We assessed the patient’s symptom improvement after the previous interventions to ensure that there was initially a stronger flow and improved ability to empty. Preoperative workup includes assessment of the patient’s urinary symptoms with the International Prostate Symptom Score (IPSS) and assessment of erectile function status with the International Index of Erectile Function (IIEF). In addition, we acquire a uroflow and a postvoid residual volume.

Next, we will perform cystoscopy. During the cystoscopy, several key maneuvers are performed. First, the anterior urethra is evaluated. We assess for any concomitant urethral strictures. At the level of the sphincter, we will have the patient perform a volitional contraction of the sphincter complex—what we call a “Kegel wink”. We are assessing if the scope can pass through the sphincter complex without any resistance. Once the scope is proximal to the external sphincter, we will evaluate the distance from the external sphincter to the BNC. This provides a guide as to the distance needed for the bladder mucosa to travel during the operation after resection of the scar tissue. An assessment of the diameter of the contracture is noted. If able, the cystoscope will be advanced through the contracture, and a retroflexed view will be performed. In some instances, the scope will pass through an otherwise narrowed BNC signifying an opening that is patent to 17 Fr, but insufficient caliber for adequate emptying given the patient’s underactive bladder. In these cases, we will still offer the operation to enhance the caliber of the bladder neck. This specific patient population has reported improvement in obstructive lower urinary tract symptoms secondary to the larger diameter bladder neck. In most cases, we additionally perform a volume assessment of the residual prostate volume with a transrectal ultrasound, computed tomography (CT) scan, or magnetic resonance imaging (MRI).

VUAS

Our workup for VUAS is similar to BNC from a history and preoperative questionnaire standpoint. In this population, the history of previous dilations and whether this resulted in any incontinence is a crucial question for postoperative expectations counseling. In our experience, patients without incontinence prior to dilations who later developed postoperative transient incontinence are more likely to have permanent postoperative incontinence after a TUITMR. Cystoscopy is then performed in a similar fashion to BNC preoperative workup. It is very common for patients to be referred for isolated VUAS but in fact, have a component of membranous urethral stricture(s) as well. This scenario is where the “Kegel wink” maneuver can elucidate membranous urethral involvement versus explicit VUAS. If the VUAS disappears during a wink, this will now categorize the narrowing as a membranous urethral stricture. This finding is most commonly seen in patients with a history of pelvic radiation therapy. Finally, we evaluate the distance from the external sphincter to the VUAS. Again, this gives us an idea of the distance the bladder mucosa will need to be advanced in order to cover the defect created once scar tissue is removed.

We have also begun requiring preoperative imaging, ideally with both non-contrast pelvic CT and MRI scans. The CT scan is conducive to identify posterior urethral calcifications (Figure 1A,1B), and the MRI scan is used to evaluate the relationship of the urethra to the rectum and pubic bone. Also, MRI scans can identify potential bladder neck dehiscence (Figure 2). This finding tends to be associated with a higher chance of rectal tethering (Figure 3), and we would thus favor alternative therapies to the TUITMR.

Contraindications

The TUITMR is not recommended for patients with bladder neck necrosis associated with soft tissue calcifications or significant dehiscence of the bladder neck. Although, in appropriately selected patients, minor calcifications (Figure 4) are treatable with TUITMR, and minor dehiscence has been successfully realigned. Additionally, if someone is found to have stenosis involving the membranous urethra, we prefer a different treatment in which we will utilize a buccal mucosa graft for urethroplasty incorporating the entirety of the stricture pathology (19). Finally, anyone found to have an associated fistula to the rectum or pubic bone should not be offered the TUITMR.

Step-by-step description

BNC

Cystoscopy is performed with a 27-Fr continuous flow sheath (A22025A, Olympus, Westborough, MA, USA). The scope is taken to the level of the BNC. If the contracture is pinpoint, the laser bridge for the Olympus sheath is attached, and a 0.035-inch sensor wire (M0066703081, Boston Scientific, Marlborough, MA, USA) is passed through the narrowing. If the BNC is obliterated, we will pass a rigid endoscopic 25-gauge needle (ET1300, Laborie, Portsmouth, NH, USA) through the laser bridge with a flexible cystoscope, using a pop-to-light technique. A sensor wire is then passed through the rigid needle. This technique has been previously described for membranous urethral strictures (20). The contracture is then dilated under vision with a 24-Fr NephroMax^®^ balloon (M0062101400, Boston Scientific). Next, the Plasma Loop^®^ (WA22737S, Olympus) is used to incise laterally at 3 and 9 o’clock until the scope can be passed into the bladder. We then begin loop resection of the scar tissue at the level of the bladder neck, working from 2 to 10 o’clock posteriorly, sparing the anterior bladder neck only. We purposefully do not resect the anterior bladder neck as we have found it difficult to place sutures at this location. In addition, there is anatomical concern of the anterior bladder neck proximity to the pubic bone and with deep resection increasing the risk of urosymphyseal fistula.

Once the scar is visually resected, we pass the loop without energy over the bladder neck tissue to assess for suppleness. Firm or calcified ridges can be appreciated. Just distal to the bladder neck, we resect deeper into the prostate to create a bladder neck shelf (Figure 5). To perform this move, we ignite the loop, drive its entirety deep into the tissue (so that the electrodes are flush with the tissue), and then let the loop retract back to the scope. This results in a deep “V” shaped bite. This bite will help to facilitate the bladder neck folding down to meet with the distal urethral margin. Importantly, any residual apical prostate adenoma is resected down to the level of the prostatic capsule, as the sutures will not hold well in the adenoma. If we were to look at the coronal plane midway through the prostate, it would have the appearance of a spinning wide at the bladder neck, wider in the mid prostate, and narrow at the distal urethra.

The resection specimens are removed, and we visualize the bladder neck during maximum bladder decompression to ensure there is mobility of the mucosa across the resection bed. Utilizing the cold loop bluntly, we can pull the tissue down to test and ensure that we have adequate mobility (Figure 6). We limit cautery use at the bladder mucosal edges and urethral edges, but will liberally cauterize the tissue between.

Next, the JNW UrTrac^®^ sheath (LSI Solutions, Victor, NY, USA) is introduced with its obturator. Once beyond the sphincter, we remove the obturator and quickly introduce the accompanying shut-off valve followed by a flexible digital ureteroscope (11278VSU, Karl Storz, Tuttlingen, Germany) down the visual port. The UrTrac^®^ is then advanced into the bladder. The RD180^®^ and the preloaded 2-0 Monoglide^®^ (LSI Solutions) are passed into the bladder. We start with bites of tissue beginning laterally, starting at the 9 o’clock position. Ideally, the needle of the RD180^®^ will pass into the bladder mucosa proximal to the resection bed rather than through the resection bed (Figure 7). This ensures that when pulled distally, we have a mucosa-to-mucosa anastomosis, eliminating a potential gap of exposed scar tissue. However, if the first stitch enters within the scar bed, often the next suture bites can accomplish the mucosa-to-mucosa anastomosis. Similarly with the distal bite, we prefer to take as little of the resection bed as possible to minimize a gap of exposed scar tissue. This is accomplished by placing the head of the RD180^®^ just over the lip of resected tissue, ensuring minimal resection bed is visually presented (Figure 8).

VUAS

The operation is initiated in a similar fashion to that described for BNCs. During the resection step, there are several key differences. We only resect laterally between 8–10 and 2–4 o’clock. This avoids any resection in the direction of the pubic bone and rectum. In addition, working laterally has prevented any complications with the ureteral orifices. During the resection, the resectoscope is held firmly at the level of the membranous urethra by pushing gently inward with the left hand as the right hand does the resection. This limits the chance of inadvertently damaging the sphincter, which is invariably more proximal to the bladder neck status post prostatectomy. In addition, the target diameter is not as wide as that with the BNC approach. Often after a prostatectomy, especially in the setting of radiation, the bladder neck mucosa is fixed and will only mobilize up to 2 cm. This can be even less in irradiated fields. Therefore, it is imperative to minimize the resection bed length from the bladder to healthy urethral mucosa. Rather than making a long incision from bladder to urethra, we make a deep incision, allowing the bladder to pull to the urethra without any bulk of scar tissue preventing the tissue from advancing. During the posterior portion, it is not uncommon to place a finger in the rectum to ensure it is well away from the loop. We place the TK Knot^®^ sutures at 10, 8, 4, and 2 o’clock.

Postoperative considerations and tasks

For cases of BNC and non-radiated VUAS, we prefer to leave the Foley catheter in for 2 weeks (14 days). This allows the bladder to stay fully decompressed, placing no tension on the new anastomosis via a filling and emptying bladder. Patients are placed on a daily antispasmodic anticholinergic or beta-3 agonist during this time and will take oral antibiotics the day of removal. For radiated VUAS, we leave the Foley in for 4 weeks and we recommend patients receive hyperbaric oxygen therapy during this month. We have several cases of initial poor healing (Figure 9A) that resolved post treatment (Figure 9B). The first postoperative follow-up is at 4 months with a uroflow [including post-void residual (PVR)], cystoscopy, updated IPSS and IIEF. The second visit is 1 year from surgery with a uroflow/PVR, IPSS and IIEF.

Anatomic success is defined as the ability to pass the cystoscope at the 4-month follow-up visit and no need for additional interventions. Functional success is defined as the ability to urinate without further interventions. Some patients who show anatomic success still require self-catheterization given bladder hypocontractility and may go on to additional interventions, such as a robotic-assisted Y-V plasty.

Possible postoperative complications include calcification formation from retained TK Knot^®^. The 4-month cystoscopy ensures the clips have passed and can be removed in-office if needed. In addition, resection of anterior or posterior tissue in the VUAS population could result in osteitis pubis or rectourethral fistula, respectively.

Tips and pearls

BNC

Positioning of the RD180^®^ when entering the sheath is pivotal. It is important that while introducing the instrument, the suture is draped over the distal aspect of the RD180^®^ as opposed to having the suture on the same side as the needle. In addition, we found that applying a thin coat of petroleum jelly to the entire shaft can lubricate the RD180^®^, thus preventing friction and coarse movements. Holding and introducing the RD180^®^ in the direction where the bite will be taken minimizes any intra-sheath twisting of the suture. For example, starting at 9 o’clock, we use our right-hand with the handle facing 3 o’clock. Once the bite is taken, ensure the hand does not twist and maintains the same orientation when reloading. This prevents misalignment of the suture and potential suture fracture (Figure 10). Practicing* ex vivo *can help improve the surgeon’s readiness with the dexterity needed. When reloading in the bladder, it is helpful to marginally advance the scope into the bladder and pull the trigger slowly to ensure the suture goes through the catch at the appropriate orientation (Figure 11).

The distal bite is then taken at the corresponding urethral margin. If you find the sutures are pulling through, it is likely due to residual adenoma. Alternatively, it could be due to excess tension on the bladder neck, and thus partial decompression of the bladder could help alleviate this. If there is excess adenoma, it is safe to back the scope to the level of the sphincter and take the bite through the sphincter muscle, as this is a more reliable anchor point. There is no need to reload after the distal bite is taken.

The suture is then loaded within the TK Knot^®^ (LSI Solutions). We prefer to pass the sheath with the distal aspect of the TK Knot^®^ exposed within the bladder. Then as the suture is tensioned externally, we will pull the sheath back to the level of the distal stitch, watching the mucosa advance as we pull. In some cases, the mucosa cannot be well visualized when tensioning, in which case we will park the scope at the distal margin, and tension by feel. Once satisfied with the amount of tension, the TK Knot^®^ is fired. Immediate release of the suture lets you know the firing was successful. If the advancement is unsuccessful, a second attempt can be made at the same location. After firing, ensure the TK Knot^®^ is free from the deployment device before removing the instrument. This is accomplished by releasing the hand piece and then rotating it from 3 to 9 o’clock several times to ensure the knot is free.

If we started at 9 o’clock, the second bite will be at 3 o’clock. At this point, there should be a good roll of bladder mucosal tissue within the fossa. Even if the alignment visually looks complete, in an effort to disperse tension, we will pass at least two additional sutures. These additional bites are equally at 5 and 7 o’clock, and occasionally also at 6 o’clock. These subsequent bites should be able to pass the needle into the mucosa and out of the mucosa. Extra bites should be taken if there is any exposed resection bed (Figure 12).

VUAS

Hemostasis is mandatory. The continuous flow via the UrTract^®^ is limited, so it is important to cycle the bladder several times and make sure visualization is optimized. Visualization can also be enhanced by leaving the bladder distended when exchanging the Olympus sheath for the UrTract^®^ sheath. Placing the ureteroscope and instruments swiftly can continue to minimize decompression, ultimately limiting bleeding and thus improving visualization.

Like the surgical recommendations provided with BNC repair, ensure the RD180^®^ enters the sheath with the suture pulled over the groove behind the head of the instrument rather than ipsilateral to the needle. When introducing the RD180^®^ into the sheath, orient the instrument in the direction where the bite will be taken. Together, these steps can limit the chance of the suture twisting or locking internally. When reloading the RD180^®^, maintain the same orientation as the bite taken, rather than rotating the grip to a neutral position. If the suture is not in line, it will shear and break in the landing zone of the head of the RD180^®^.

Discussion

Success of the TUITMR approach to repair bladder neck obliterative scarring by utilizing healthy bladder urothelium is highly dependent upon technique. This is the first endoscopic modality that uses bladder mucosa to treat BNC and VUAS. The potential advantages of this approach will be explored.

Increased rate of success with fewer repeat endoscopic procedures and without adverse safety events

The current management strategies of BNC vary from urethral dilation, endoscopic incision, open reconstruction, and most recently to robotic-assisted reconstruction (21-24). Non-invasive, office-based urethral dilation followed by self-intermittent catheterization is a viable option for the non-surgical patient. This method of treatment relies heavily on patient compliance and therefore has varying rates of long-term success. Patients choosing to undergo endoscopic cold-knife incision may require multiple treatments with success rates significantly decreasing after the second repeat intervention (25). Experimental endoscopic techniques with incision followed by injection of triamcinolone or mitomycin C have raised concerns of safety profile and risk of bladder neck necrosis (26). The TURNS Study group showed a 7% rate of serious adverse events related to mitomycin C, with some patients requiring cystectomy (27). Treating BNC without adjuvant medication by optimizing surgical technique is also being explored. Deep lateral transurethral incisions of BNC (TUIBNCs) have shown to be an effective treatment for BNC. There has been reported success rate of 72% after one treatment and 86% after a second attempt with a 9% rate of* de novo SUI (9). In our endoscopic treatment, we are utilizing healthy urothelium without the use of injectable materials. Our early results have demonstrated a success rate of 89% after one treatment and 100% after a second attempt, notably without de novo *stress incontinence.

Endoscopic versus robotic mucosal realignment

To our knowledge, there are no publications investigating the direct comparison of patient morbidity with endoscopic versus robotic management of posterior urethral stenosis. Robotic-assisted surgery offers some advantages when evaluating surgical approach and success. It is a treatment option for patients who have failed prior therapies, have significant dystrophic calcification, or have concomitant pathophysiology (e.g., fistula to the urinary tract) needing surgical intervention (28-30). Intraoperatively, given the larger working area within the pelvis, one is afforded more surgical complete revision of anastomosis, bladder flaps, and flap interpositions to enhance wound healing. This may allow for improved surgical outcomes (31). However, there are well-known risks specific to robotic surgery, including longer operations, more complex positioning with resultant physiologic effects, and increased cost (32-35). Certain patients may be poor candidates for robotic surgery given comorbidities or prior surgical history.

Patients with early dystrophic calcifications

Dystrophic calcification poses an ongoing management problem in a variety of medical specialties. A substantial recurrence rate of 13.3% has been reported after simple surgical resection (36). There are four hypotheses regarding the formation of dystrophic calcification specific to the bladder (I) urine stasis at the prostatic fossa can result in the formation of urethral calculi; (II) debris or foreign bodies after surgery can serve as a nidus for calculi formation; (III) coagulative necrosis caused by cauterizing energy can promote calcification in the setting of tissue damage; and (IV) urinary tract infections can create alkaline urine, which promotes calcification (37,38). In addition, we know biochemically that dystrophic calcification commonly occurs in sites of previous inflammation or damage. This is due to (I) damaged cell membranes leaking calcium ions creating local oversaturation; and (II) necrosis creating an acidic environment that lacks inhibitors of calcification (39). These mechanisms are proposed explanation for why pelvic radiation exposure is commonly also associated with bladder neck dystrophic calcifications. A published case report showed that initial surgical resection resulted in a rapid 2-week recurrence. The authors demonstrated resolution during the second treatment by using cold, gentle scraping of the calcifications to avoid further tissue trauma and thermal damage (40). The proposed mechanism of clinical success is to create an environment that first allows complete wound healing to interrupt the vicious cycle of dystrophic calcification recurrence (41). Currently, many recommended treatment options for posterior urethral stenosis utilize trauma and/or electrocautery, thereby increasing the risk of recurrent dystrophic calcification. With our technique, the resected tissue is covered with healthy mucosa, thus minimizing coagulative necrotic tissue surface exposure. We have seen our approach to be curative of minimal dystrophic calcification at the 1-year postoperative time point, with the potential to produce similar long-term results of calcification resolution.

Conclusions

Thousands of patients every year undergo prostate surgery for malignancy or benign prostatic hyperplasia (42,43). While the field has improved its surgical techniques over the years, the rates of VUAS and BNC are still prevalent and a known complication after a variety of prostate surgeries. The current techniques provide varying rates of success or utilize more invasive approaches. Recurrent dilations or thermal resections have intermediate success rates with worsening results if the patient has a prior history of pelvic radiation. We propose a surgical technique that utilizes healthy mucosal tissue to ultimately provide a long-lasting and potentially permanent solution to an ongoing expected complication of prostate surgery. Whilst this is a promising technique, we recognize this is a small case series performed by a single surgeon and would benefit from a larger study population.

Supplementary