Background

Male urethral stricture disease (USD) has an estimated prevalence of 0.6%. The most typical way men present with USD is with obstructive voiding symptoms (eg, slow urinary flow). However, up to 10% of patients will present without a history of bothersome symptoms and may only be diagnosed after a difficult urethral catheterization or during evaluation of recurrent urinary tract infections or urinary retention. USD can affect any part of the male urethra but most frequently affects the bulbar (43%) and penile (37%) segments.

Treatment approaches for USD range from minimally invasive endoscopic techniques (eg, urethral dilation, direct visual internal urethrotomy) to open urethral reconstruction, which often uses local fasciocutaneous flaps and/or autologous tissue grafts. Historical success rates for endoscopic management range from 0% to 50%, with higher success rates being noted for shorter bulbar strictures that have not previously been managed surgically. Repeat endoscopic management is usually unsuccessful. Open surgical techniques have significantly higher success rates, ranging from 50% to 98%, with higher success rates generally being reported for shorter bulbar repairs that do not require flaps or grafts. Overall, success rates correlate well with the complexity of the repair.

The most commonly performed treatments for USD continue to be endoscopic despite the lower reported success rates. The apparent underuse of open urethral reconstruction in favor of endoscopic intervention is likely multifactorial, resulting from the relative simplicity of endoscopic techniques and the lack of familiarity and comfort with open techniques by many surgeons. Highlighting the educational deficits was a study by Bullock and Brandes, which showed that, although 63% of urologists treated 6 to 20 urethral strictures in a given year, less than half of these urologists ever performed urethroplasty. In addition, side effects of urethroplasty, namely erectile dysfunction (ED) and urinary incontinence, are generally believed (falsely) to be more common than the literature supports, perhaps influencing both patient and provider enthusiasm for the procedures.

Changing Practice Patterns for Urethral Stricture Disease

Attitudes about the treatment of USD seem to be changing, however, as demonstrated by a recently published article buy Liu and colleagues, which showed a dramatic shift in the initial USD management over the past decade. The study revealed that, in 2004, urethroplasty was performed for USD only 2.3% of the time but, by 2012, the rate had increased to 7.6%. In addition, the years in practice seemed to be significantly associated with performance of urethroplasty, with newly certifying urologists being 3.7 times more likely to perform urethroplasty than their recertifying colleagues. This change in attitudes is likely being spurred by a the rising number of Genitourinary Reconstructive Society fellowships in the United States, more urethroplasties being performed in academic training centers, and the increase in academic interest in the field, particularly in outcomes of procedures that are performed to improve quality of life (ie, nononcologic surgeries).

Renewed academic interest in urethral reconstruction has forced the specialty to ask fundamental questions about the surgeries performed, the most basic of which is, “What constitutes a surgical success?” Traditionally, the academic definition of a successful urethroplasty has been defined as the lack of need for a secondary procedure. This definition is easily definable and, importantly, easy to quantitate using retrospective methodologies. However, the definition is also inherently subjective because it assumes that patient with recurrent symptoms will seek care at the center in which the urethroplasty was performed (ie, the patient did not go elsewhere for treatment); assumes equal utilization (both patient and provider) of secondary procedures for postoperative strictures; and, importantly, does not account for asymptomatic recurrences (ie, posturethroplasty decrease in urethral lumen size for which the patient does not have associated voiding symptoms), which have recently been shown to occur in up to 35% of recurrent strictures diagnosed by routine cystoscopy.

Intimately associated with the question of how to define surgical success is the question “What is the best way to monitor the posturethroplasty patient?” With historical success rates being high and USD ultimately being a quality of life condition (ie, rarely does USD lead to mortality), excessive monitoring of the posturethroplasty patient is a legitimate concern because most urethroplasties will be ultimately be deemed successful. In addition, although academicians may be interested in topics such as postoperative urethral lumen size, most patients only care about their ability to empty their bladder in an appropriate and timely fashion. The ideal follow-up strategy must be able to account for both surgeon and patient concerns: maintaining the surgeon’s ability to objectively define success (and failure) and protect patient’s genitourinary health (ie, prevent bladder or renal dysfunction), all while preventing patients from undergoing unnecessary testing that leads to unnecessary cost, discomfort, anxiety, and risk.

Thus, the purpose of this article is 2-fold. This article reviews the literature for current definitions of surgical success and the current means by which the reconstructed urethra is monitored. It then proposes both a definition of success and a follow-up strategy that considers the concerns of both the patient and physician as previously listed.

Background

Male urethral stricture disease (USD) has an estimated prevalence of 0.6%. The most typical way men present with USD is with obstructive voiding symptoms (eg, slow urinary flow). However, up to 10% of patients will present without a history of bothersome symptoms and may only be diagnosed after a difficult urethral catheterization or during evaluation of recurrent urinary tract infections or urinary retention. USD can affect any part of the male urethra but most frequently affects the bulbar (43%) and penile (37%) segments.

Treatment approaches for USD range from minimally invasive endoscopic techniques (eg, urethral dilation, direct visual internal urethrotomy) to open urethral reconstruction, which often uses local fasciocutaneous flaps and/or autologous tissue grafts. Historical success rates for endoscopic management range from 0% to 50%, with higher success rates being noted for shorter bulbar strictures that have not previously been managed surgically. Repeat endoscopic management is usually unsuccessful. Open surgical techniques have significantly higher success rates, ranging from 50% to 98%, with higher success rates generally being reported for shorter bulbar repairs that do not require flaps or grafts. Overall, success rates correlate well with the complexity of the repair.

The most commonly performed treatments for USD continue to be endoscopic despite the lower reported success rates. The apparent underuse of open urethral reconstruction in favor of endoscopic intervention is likely multifactorial, resulting from the relative simplicity of endoscopic techniques and the lack of familiarity and comfort with open techniques by many surgeons. Highlighting the educational deficits was a study by Bullock and Brandes, which showed that, although 63% of urologists treated 6 to 20 urethral strictures in a given year, less than half of these urologists ever performed urethroplasty. In addition, side effects of urethroplasty, namely erectile dysfunction (ED) and urinary incontinence, are generally believed (falsely) to be more common than the literature supports, perhaps influencing both patient and provider enthusiasm for the procedures.

Changing Practice Patterns for Urethral Stricture Disease

Attitudes about the treatment of USD seem to be changing, however, as demonstrated by a recently published article buy Liu and colleagues, which showed a dramatic shift in the initial USD management over the past decade. The study revealed that, in 2004, urethroplasty was performed for USD only 2.3% of the time but, by 2012, the rate had increased to 7.6%. In addition, the years in practice seemed to be significantly associated with performance of urethroplasty, with newly certifying urologists being 3.7 times more likely to perform urethroplasty than their recertifying colleagues. This change in attitudes is likely being spurred by a the rising number of Genitourinary Reconstructive Society fellowships in the United States, more urethroplasties being performed in academic training centers, and the increase in academic interest in the field, particularly in outcomes of procedures that are performed to improve quality of life (ie, nononcologic surgeries).

Renewed academic interest in urethral reconstruction has forced the specialty to ask fundamental questions about the surgeries performed, the most basic of which is, “What constitutes a surgical success?” Traditionally, the academic definition of a successful urethroplasty has been defined as the lack of need for a secondary procedure. This definition is easily definable and, importantly, easy to quantitate using retrospective methodologies. However, the definition is also inherently subjective because it assumes that patient with recurrent symptoms will seek care at the center in which the urethroplasty was performed (ie, the patient did not go elsewhere for treatment); assumes equal utilization (both patient and provider) of secondary procedures for postoperative strictures; and, importantly, does not account for asymptomatic recurrences (ie, posturethroplasty decrease in urethral lumen size for which the patient does not have associated voiding symptoms), which have recently been shown to occur in up to 35% of recurrent strictures diagnosed by routine cystoscopy.

Intimately associated with the question of how to define surgical success is the question “What is the best way to monitor the posturethroplasty patient?” With historical success rates being high and USD ultimately being a quality of life condition (ie, rarely does USD lead to mortality), excessive monitoring of the posturethroplasty patient is a legitimate concern because most urethroplasties will be ultimately be deemed successful. In addition, although academicians may be interested in topics such as postoperative urethral lumen size, most patients only care about their ability to empty their bladder in an appropriate and timely fashion. The ideal follow-up strategy must be able to account for both surgeon and patient concerns: maintaining the surgeon’s ability to objectively define success (and failure) and protect patient’s genitourinary health (ie, prevent bladder or renal dysfunction), all while preventing patients from undergoing unnecessary testing that leads to unnecessary cost, discomfort, anxiety, and risk.

Thus, the purpose of this article is 2-fold. This article reviews the literature for current definitions of surgical success and the current means by which the reconstructed urethra is monitored. It then proposes both a definition of success and a follow-up strategy that considers the concerns of both the patient and physician as previously listed.

Absence of Secondary Procedures

A systematic review by Meeks and colleagues revealed that 75% of the academic literature on urethral reconstruction published between 2000 and 2008 used the absence of a secondary procedure, regardless of urinary symptoms or the appearance of the reconstructed urethra, as the definition of surgical success. As previously noted, there are many logistical advantages to using such a definition; namely that this definition requires very little time or effort on either the patients’ or the provider’s part. However, this definition says very little about what is actually happening inside the urethral lumen (too big or too small?) or, for that matter, inside of patients’ heads (ie, are they satisfied?). The definition also prevents surgeons from doing a true comparison between surgical techniques. For example, postvoid dribbling is a commonly reported postoperative complaint or complication after a few types of urethroplasties but few surgeons would recommend a surgical procedure to correct it. Yet, should a patient with significant postvoid dribbling be considered a surgical success?

It is likely that, despite its limitations, this definition of success will remain popular both in practice and publications. However, this article attempts to show that, with risk stratification, urethroplasty specific objective follow-up, and patient-specific noninvasive follow-up strategies, this definition can potentially become more scientifically valid. Using a data-driven, standardized follow-up regimen will add more weight and significance in future publications to the cases of urethroplasty patients who have not undergone secondary procedures.

Objective Measurements

Cystoscopy and retrograde urethrogram (RUG) are objective means to monitor a reconstructed urethra and are often considered to be the gold standard follow-up methodologies. A flexible cystoscopy is easy to perform, relatively safe and is perhaps the most reliable way to compare the anatomy of a reconstructed urethra among patients and between centers. RUG has a few advantages compared with cystoscopy in that it can visualize the entire urethra simultaneously, may be able to more easily diagnose diverticula and fistulas, and is easier to compare to preoperative to postoperative objective findings. However, it is logistically difficult to perform in a standardized fashion and thus its interpretation can be considered subjective.

The Trauma and Urologic Reconstruction Network of Surgeons (TURNS; www.turnsresearch.org ), which is a network of 13 urologic reconstructive centers (and 14 surgeons) across the United States, uses a cystoscopy at 3 and 12 months to determine anatomic success, using the “inability to traverse the reconstructed urethra without force” as the definition of failure. Using this protocol, the group found that 1-year success rates were significantly lower than had previously been reported (88.5% and 77.5% for excisional and substitutional repairs, respectively), likely due in large part to the nearly 35% of subjects with failure that were asymptomatic. These are subjects with anatomic recurrences that would have been missed had the traditional definition of failure, secondary operations, been used, and thus reported success rates would have been much higher.

The cystoscopic protocol developed by the TURNS group was designed to be easily interpretable and reproducible across all centers. However, the findings perhaps created more questions than provided answers. For instance, what is the significance of the asymptomatic recurrences found in those subjects? Surgeons know that many classic obstructive symptoms will not generally develop until the urethral lumen is less than 16 F in size but does finding the recurrence early before symptoms develop offer long-term advantages to patients? Perhaps early detection (eg, for a distal graft recurrence) would prevent high intraurethral pressures within the graft but at what cost to the patient? Additionally, despite these subjects all consenting to the study protocol, compliance with 1-year cystoscopic follow-up was low, averaging only 54.4%, with many of subjects saying they did not follow-up because of a lack of symptoms, a lack of time, and in some cases, aversion to the impending cystoscopy. Can a protocol in which nearly half of patients opt out really become a practical gold standard? Can surgical outcomes of a reconstructive procedure truly be compared without looking at the postoperative anatomy?

Noninvasive Objective Measurements

In the Meeks and colleagues review, uroflowmetry (UF) was found to be performed in 56% of urethroplasty outcomes papers to screen for recurrence. UF is a noninvasive test that most commonly provides 3 metrics, maximum flow rate (Q _m ), average flow rate (Qa), and voided volume (VV), which can then be used to evaluate flow dynamics. The utility of the UF diminishes significantly (and is often disregarded) when the VV is less than 150 mL but, otherwise, VV is of little utility for screening purposes other than to help determine Q _m and Q _a . The Q _m is the most widely cited measure to screen for recurrence, with many articles citing (arbitrarily) Q _m cut points ranging from 10 to 15 mL/s. A postoperative patient with a flow below this threshold is generally then screened with cystoscopy or RUG for recurrence. However, although simple to understand and perform, UF has never been validated to be a very useful as a stand-alone tool for stricture recurrence screening.

The few studies that have specifically studied its utility have found that it works best when either combined with symptom analysis or when personalized to the specific patient. Erickson and colleagues noted that using a Q _m of 10 mL/s in their postoperative subjects was only 54% sensitive at detecting recurrence. However, when UF was combined with symptoms and/or an obstructive voiding curve, the sensitivity increased to 99% (as did the negative predictive value) with an acceptable specificity of 98%. This same group then analyzed subject-specific changes in Q _m and noted that when the Q _m increases by less than 10 mL/s postoperatively, these subjects are at high risk of recurrence. In their retrospective cohort, had a ΔQ _m of less than 10 mL/s been used to screen for recurrence, it would have been 92% sensitive and 78% specific. Importantly, these studies were retrospective in nature and were likely biased because subject follow-up compliance was heavily influenced by the presence of symptoms. Another study by Heyns and Marais noted that UF (Q _m <15) combined with the American Urologic Association Symptom Index (AUASI; total score>10) could help to predict strictures in untreated subjects, revealing a sensitivity of 93%, with a 68% specificity. However, this study did not specifically discuss its use in the postoperative patient.

A more recent study by Tam and Erickson and colleagues evaluated the TURNS database and attempted to validate the routine use of UF specifically for diagnosing recurrence of stricture. The group found that a Q _m of less than 15 mL/s, a commonly cited cut-off in the literature when screening for urethroplasty, was only 41% sensitive for detecting cystoscopic recurrences (defined as the inability to traverse the urethroplasty site with a flexible cystoscopy). However, the use of Q _m , and a novel parameter of Qm – Qa (the value obtained when subtracting the Q _a value from Q _m ), were significantly more useful in the postoperative period for men under 40 years of age. Using receiver operating characteristic (ROC) curves, the group found the area under the curve (AUC) to be 0.932 and 0.922 for Qm – Qa and Q _m , respectively in men younger than 40 years, as compared with 0.748 and 0.766 in men greater than 40. The group hypothesized that this was likely because in younger men UF numbers are less influenced by the prostate and/or bladder dysfunction. In addition, the group hypothesized that the Q _m – Q _a parameter may be a useful numerical representation of the shape of the voiding curve, a somewhat subjective parameter that has been shown to be a useful indicator of obstruction compared with the Q _m value.

The measurement of the post-void residual (PVR), generally with the assistance of bladder ultrasound, has also been cited as a useful too when evaluating the reconstructed urethra, though generally as an adjunct to other noninvasive measurements. In the Meeks and colleagues study, only 8% of articles cited PVR as a way to screen for recurrence after urethroplasty. However, because PVR depends on the hydration status of the patient, the timing of the last void relative to the test performance, the familiarity with the ultrasound machine by the tester, body habitus of the patient, and the variability in measurement algorithms by individual ultrasound machines, PVR is unlikely to ever become a useful stand-alone tool to monitor the reconstructed urethra. It may be useful, however, in identifying urethral stricture patients at risk for bladder failure (and potentially obstructive renal failure), though this is rare in younger population, most of whom can still empty their bladder even with USD.

Voiding Patient-Reported Outcomes Measures

For quality of life conditions such as USD, patient symptoms ultimately drive medical care. Urethral stricture patients will often seek care for obstructive voiding symptoms, such as urinary hesitancy and slow urinary flow. Thus, it seems reasonable to use validated patient-reported outcomes measures (PROMS) to evaluate urinary symptoms preoperatively and postoperatively, and to potentially use these PROMS to screen for recurrence because most patients would be expected to have new or persistent voiding symptoms.

One of the first studies to evaluate the use of a validated voiding questionnaire for screening purposes was conducted by Morey and colleagues, showing that AUASI scores improved significantly after a successful urethroplasty. In this study, 9 out of 50 subjects had recurrence of their stricture and none of these subjects had significant improvements in their overall score postoperatively (as opposed to successful urethroplasties that decreased their score from 27 to 5), indicating that the AUASI may be useful for screening purposes. In the Heyns and Marais study mentioned previously, the addition of the AUASI score to the UF data improved the sensitivity to screen new USD.

Unfortunately, although it might be intuitive to think that all patients with recurrence of their stricture after urethroplasty would be symptomatic, a study of TURNS data by Erickson and colleagues shows that many men with anatomic recurrence will be asymptomatic. In the study of 213 men, only 13 of 20 recurrences (65%) presented with urinary symptoms, implying that PROMS alone could miss recurrences in more than one-third of urethroplasty patients. The potential limitations of PROM-only screening were recently validated in a study by Tam and colleagues. Again, using TURNS data, the study revealed that after comparing the International Prostate Symptom Score (IPSS) to cystoscopy findings, the IPSS was only 50% sensitive in detecting anatomic recurrences when using a commonly used IPSS total score cutoff of 10. Furthermore, on ROC analysis, single questions from the study (ie, urinary quality of life and weak stream) outperformed the total questionnaire (AUC 0.66 and 0.60 vs 0.56, respectively), which emphasizes that, not only are these generic voiding questionnaires not helpful for USD patients, they fail to ask the specific questions that might be necessary to detect early recurrence (eg, “Has the strength of your urinary flow diminished since your catheter was initially removed?”).

However, that approximately one-third of recurrences are asymptomatic begs the question, “what is the significance of the asymptomatic recurrence?” As previously stated, because USD is ultimately a quality of life condition, if the patient is without symptoms (and presumably in no danger of bladder and/or renal failure), why should surgeons care? The primary reason is that, without knowledge of the anatomic detail of the reconstructed urethra, different reconstructive options cannot be compared, such as between an excisional repair to a graft repair.

Nonvoiding Patient-Reported Outcomes Measures

Because open urethral reconstructive surgery involves surgery in the perineum and/or genitalia, patient concern for postoperative sexual dysfunction is understandably high. The reported rates of postoperative sexual dysfunction vary widely but a systematic review has shown that rates of permanent, de novo sexual dysfunction are likely around 1%. However, transient ED has been reported to be as high as 40% at 3 months, with most studies showing improvement to baseline by 6 to 12 months.

With such low rates of expected long-term ED, does it even need to be routinely assessed? The authors believe the need to fully compare different types of surgeries and different surgeons requires comparison of not just anatomic outcomes but factors that are important to the patient, including ED. A recent TURNS study that evaluated satisfaction after anterior urethroplasty depended on 3 factors independent of anatomic success: erectile function, pain, and voiding symptoms. Therefore, even if the surgeon created a widely patent urethra, if the patient had ED (even transient), new pain, or they did not perceive their urinary function to be improved, they were unhappy. Thus, these nonvoiding parameters should be a standard part of any complete urethroplasty follow-up to allow for assessment of the entire postoperative outcome.

Unfortunately, a standardized, validated questionnaire that assesses many of these symptoms does not exist specifically for anterior urethroplasty. The Jackson and colleagues questionnaire assesses many voiding and quality of life measures. The questions, most of which were adopted from other questionnaires, were validated for the population but it was not developed with patient input. Newer questionnaires are currently in development that aim to take a more patient-centered approach to determining surgical outcomes.