Objectives: To investigate the versatility of the ventral urethrotomy approach in the bulbar reconstruction with buccal mucosa (BM) grafts placed on the dorsal, ventral or dorsal plus ventral urethral surface.
Methods: Between 1999 and 2008, 216 patients with bulbar strictures underwent BM graft urethroplasty using the ventral-sagittal urethrotomy approach: 32 (14.8%) patients (mean stricture 3.2 cm, range 1.5 – 5) had dorsal graft urethroplasty (DGU), 121 (56%) patients (mean strciture 3.7, range 1.5 – 8) ventral graft urethroplasty (VGU) and 63 (29.2%) patients (mean strciture 3.4, range 1.5 – 10) dorsal plus ventral graft urethroplasty (DVGU). The strictured urethra was opened by a ventral-sagittal urethrotomy and BM graft was inserted dorsal or ventral or dorsal plus ventral to augment the urethral plate.
Results: Median follow-up was 37 months. The overall 5-year actuarial success rate was 91.4%. The 5-year actuarial success rates were 87.8%, 95.5% and 86.3% for the DGU, VGU and DVGU, respectively. There was no statistical significant difference between the 3 groups. Success rates decreased significantly only with stricture length > 4 cm.
Conclusions: In BM graft bulbar urethroplasties the ventral urethrotomy access is a simple and versatile technique, allowing intraoperative choice of dorsal, ventral or combined dorsal and ventral grafting with comparable success rate.
Buccal mucosa (BM) is considered the gold standard urethral substitute in graft bulbar urethroplasties and its dorsal or ventral placement using dorsal or ventral urethrotomy approaches has become a contentious issue without winners [ 1, 2 ].
In 1953, Presman introduced the ventral grafting by a ventral urethrotomy which gives an easy access to the urethra and a good visualisation of the stricture [ 3 ].
In 1996, this technique was revived by Morey and McAninch [ 4 ]. In 1996, Barbagli introduced the novelty of the dorsal grafting by the dorsal urethrotomy [ 5 ]. Nevertheless, the same Author recognized that dorsal approach is simpler in the distal bulbar urethra, whereas ventral approach with ventral grafting is more efficacious in the proximal bulbar urethra, where the spongiosum tissue is thick [ 6 ]. Also he advised that the dorsal access might damage the erectile function and the bulbar arteries when the dissection from the corpora needs to be very proximal [ 6, 7 ]. The dorsal urethral mobilisation proved itself to be difficult in scarred urethras with marked periurethral fibrosis following prior treatments[ 8 ]; even an extensive dorsal approach could cause urethral ischemia. Therefore, in 2001, Asopa described a different dorsal grafting by a ventral urethrotomy approach stating that the procedure is easier because the urethra is not mobilized [ 8 ]. Recently, Kulkarni and Barbagli elaborated a modified dorso-lateral approach which preserves one lateral vascular supply to the urethra [ 9 ].
In 2008, we described, for the first time, the combined dorsal plus ventral double graft for the repair of very tight bulbar strictures [ 10 ]. To investigate the feasibility, efficacy and versatility of the ventral approach, in this study we performed a retrospective evaluation and statistical analysis of outcomes in 216 patients who underwent graft bulbar urethroplasty using the ventral urethrotomy access and with the BM placed on the dorsal, ventral or dorsal plus ventral surface of the urethra. We also analysed the risk factors that could affect the success rate over a median follow-up period of 37 months using both bivariable and multivariable analyses.
Material and Methods
We reviewed the charts of patients with bulbar urethral strictures who underwent BM graft bulbar urethroplasty by a ventral-sagittal urethrotomy approach. The study included 216 consecutive patients who were treated between 1999 and 2008 and completed a minimum follow-up period of 12 months. None of the patients were lost for follow-up. Patients with lichen sclerosis and failed hypospadias repair were excluded. The study population was divided into 3 groups according to the location of the BM graft: dorsal, ventral or combined dorsal and ventral.
The techniques were selected according to the site and length of the stricture within the bulbar urethra, and according to the urethral plate quality. Generally, we used the dorsal graft in strictures located in distal or middle bulbar urethra where, following the incision of the urethral plate, it is easy to expose the corpora. The ventral graft was preferred in strictures located in proximal bulbar urethra where it is difficult to work dorsally and the split of the corpora causes the lack of adequate support for the graft; furthermore, the abundant ventral spongiosum provides adequate vascularization and support for the graft [ 4 ] . Finally, the dorsal plus ventral double graft was used in tight strictures with narrow residual urethral plate ( < 5 mm ) in which a single patch seemed to be insufficient to make a wide enough lumen.
Baseline patients and strictures characteristics are shown in table 1. Preoperative evaluation included clinical history, physical examination, oral cavity examination, urine culture, uroflowmetry, retrograde and voiding cystourethrography and urethroscopy. All patients were informed of the rare postoperative complications at the oral donor site.
All surgical procedures were carried out by the same urologist (E.P.). Through a Y-inverted incision the bulbocavernous muscles were divided, exposing the bulbar urethra. The strictured tract was opened by the ventral-sagittal urethrotomy approach, exposing the urethral plate, and then the BM patch graft was inserted dorsally, ventrally or dorsally-ventrally to augment the urethra (fig. 1). Of 216 urethroplasties, the graft was placed on the dorsal urethral surface by Asopa technique in 32 (14.8%) cases, on the ventral surface in 121 (56%) and on the dorsal plus ventral surface by our previously described technique [ 10 ] in 63 (29.2%).
Dorsal graft urethroplasty (DGU):
The exposed dorsal urethral plate was incised in the midline down to the tunica albuginea. The margins of the incised dorsal urethra were dissected from the tunica without lifting the two halves of the bisected urethra. An elliptical raw area was created over the tunica where the graft was placed and sutured. The catheter was inserted and the lateral margins of the augmented urethral plate were sutured together with a running suture. Finally the adventitia of the spongiosum was closed [ 8 ].
Ventral graft urethroplasty (VGU):
The graft was sutured to the mucosal margins of the exposed dorsal urethral plate. A few stitches fixed the ventral spongiosum to the graft. Finally the adventitia of the spongiosum was closed over the graft [ 4, 11 ].
Dorsal plus ventral graft urethroplasty (DVGU):
The exposed dorsal urethral plate was incised in the midline to create an elliptical area where the first dorsal-inlay graft was placed to augment the urethra dorsally. Subsequently, the second ventral-onlay graft was sutured to the lateral urethral margins to complete ventrally the augmented urethroplasty by preserving the urethral plate. Finally, the spongiosum was closed over the graft [ 10 ] .
Harvesting of BM
The BM was harvested from the cheek. Of 153 DGUs and VGUs the BM was harvested from the right cheek in 152 patients and from both cheeks in 1. Of 63 DVGUs, 58 patients had a wide single graft harvested from one cheek and subsequently tailored into two smaller grafts according to the length of the dorsal and ventral urethral openings, while in 4 patients the two grafts were harvested bilaterally from both cheeks.
Average length of the harvested BM graft was 6 ± 0.36 cm (range 5 – 8) and average width was 1.7 ± 0.38 cm (range 1 to 2.5).
A suction drain was left in place for 2 days. An 18 Fr. Foley catheter was left in place for 3 weeks. Patients were usually discharged from the hospital 3 days after the surgery and voiding cystourethrography was performed 3 weeks later.
Follow up assessment included recording of post-urethroplasty complaints (urinary, genital and ejaculatory) by simple clinical interview, uroflowmetry and urine culture every 4 months in the first year and annually, thereafter.
Whenever obstructive symptoms developed or peak flow rate deteriorated < 14 ml. /s, urethrography and urethroscopy were performed. Successful reconstruction was defined as normal voiding without need for any postoperative procedure, including dilation [ 4, 6, 10 ].
All patients were followed for a minimum duration of 12 months, mean 37 ± 19.8 months (range 12 – 113).
Data were presented as mean ± SD or median.
Comparison between groups was carried out by Chi square and student’s t tests. The 5-year actuarial success rates were estimated by the Kaplan Meier curves and difference between groups was calculated by the Log Rank test. Study of the risk factors was carried out by the calculation of the Odds ratio using bivariable analyses.
To study the independent effect of the prognostic factors on estimates of success rate, only at least borderline significant variables, were entered into a multivariable analysis of Cox proportional hazards model. Statistical significance was considered if the P value was < 0.05. Statistical analysis was performed using the SPSS 12.0 software.
The study was approved by the local ethical committee.
In 11 (5%) cases, at the voiding urethrography after catheter removal, we observed a fistula that resolved spontaneously with a 12 Fr catheter for two additional weeks: 2 cases were in the DGU group, 5 in the VGU group, and 4 in the DVGU group. Two patients had a perineal hematoma that was drained the third day after surgery.
The overall 5-year actuarial success rate of the whole series was 91.4%. The 5-year actuarial success rates were 87.8%, 95.5% and 86.3% for the dorsal, ventral and combined dorsal and ventral grafts, respectively. There was no statistically significant difference between the 3 groups (figure 2-a, P = 0.162). The stricture length had a significant impact on the 5-year actuarial success rate with strictures < 4 cm having better prognosis (figure 2-b, P = 0.026). Patients with no history of urethral dilation prior to treatment had better 5-year actuarial success rate with a trend towards significance (figure 2-c, P = 0.058). On the other hand, patient’s age, previous urethrotomy and previous urethroplasties had no statistically significant (p> 0.05) impact on the 5-year actuarial success rate (table 2).
Significant and borderline significant variables on bivariable analyses were entered into a multivariable Cox proportional hazard model. Stricture length was the only independent factor that sustained statistical significance on the multivariable analysis. The Odds of failure among cases with stricture length of > 4 cm was 3 times more than those with a length of < 4 cm, with a 95% confidence interval of 1.09 – 8.22.
Among successful cases, there was a marked improvement of Qmax from a mean preoperative value of 8.64 (range 2-15) ml/s to a mean postoperative value of 28.54 (range 14-49.6) ml/s at the last follow-up (P<0.001).
Sexual complaints were not reported by any of the patients. Of 16 failures, 3 were in the DGU group, 5 in the VGU group, and 8 in the DVGU group. Ten patients developed a short re-stricture at the distal or proximal site of the reconstruction; they were treated with 1 internal urethrotomy in 9 cases and with 2 urethrotomies in 1 case. In 6 patients, the re-stricture involved the entire grafted area; they were treated with perineostomy and are currently waiting for a staged solution.
In our experience, using the ventral approach, the ventral, dorsal and dorsal-ventral grafting techniques showed good 5-year actuarial success rates (95.5%, 87.8% and 86.3%; respectively). Our ventral graft urethroplasties showed a success rate (95.5%) similar to 90-91.4% reported by other authors[ 11, 12 ]. Our dorsal graft urethoplasties by a ventral urethral approach showed a success rate (87.8%) similar to dorsal graft techniques by a dorsal urethrotomy approach (90-98%) as reported by other authors using similar follow-up time [ 2 ] . On the other hand, even if many surgeons prefer to use the popular dorsal approach, recent overviews have confirmed that ventral or dorsal graft procedures have a similar success rate [ 13, 14 ]. Thus, larger prospective randomized studies with longer follow-up will be necessary to analyze the outcome differences between the two approaches.
Our success rate (90%) of graft urethroplasties for strictures ranging from 1.5 to 2 cm was comparable with success rates (87-96%) of different series of Aus [ 12, 15 ]. Al-Qudah and Santucci suggested that AU is controversial in the treatment of urethral strictures ranging from 0.5 to 3 cm. They presented a series of short strictures treated with AU or BM graft and compared the results: the recurrence rate was 7% in the AU group and 0% in the BM group; sexual complications occurred in 18% of the patients after AU [ 16 ]. In our series, none of the patients reported sexual disfunctions. Nevertheless, similar to other investigators [ 17 ], we did not use a validated questionnaire for proper assessment of the sexual function. Thus, bigger series with longer follow-up and adapted questionnaires will be necessary to clarify whether, for short non-obliterative bulbar strictures, graft techniques could represent an alternative to the traditional AUs which are supported by the current evidence as the method of choice. Traditionally, the old ventral urethrotomy access has been considered an easy access to the urethral lumen which gives a good visualisation of the strictured tract [ 3, 4, 11 ]. As there is no mobilisation-rotation of the urethra, it is very simple to perform, particularly for reconstructive urologists in training with not enough experience.
The better visualisation of the urethral plate by the ventral opening may allow any of the 3 solutions: dorsal, ventral, or dorsal plus ventral graft augmentation. The choice of the graft placement is conditioned by the site of the stricture within the bulbar urethra and by the urethral plate characteristics. Generally, we used the dorsal graft in strictures located in the distal or middle bulbar urethra where the corpora represent a valid support for the graft. In the proximal bulbar urethra the split of the corpora causes the lack of this support; furthermore the difficulty to work dorsally in the deep bulb and the hearty ventral spongiosum encourage the ventral grafting [ 6 ]. In tight strictures with a very narrow urethral plate in which a single patch seemed to be insufficient to reconstruct an adequate lumen, we preferred the dorsal plus ventral double grafting. Also, McAninch group stated that in the presence of a very narrow urethral plate the standard ventral augmentation could be inadequate, suggesting the use of a 2.5 mm wider graft [ 11 ].
In 2008, we introduced the use of DVGU postulating some advantages [ 10 ]. Avoiding a wide single ventral graft, the double grafting may decrease the chance of fistulas and diverticulum. The dorsal augmentation is rather small due to the difficulty of mobilization of the urethral plate that the ventral approach entails; so, the additional second graft could correct the initial use of a single dorsal graft that was later judged to be insufficient for an adequate augmentation. Avoiding the complete section of the spongiosum, the DVGU preserves the urethral plate and the urethral vascularity [ 10, 18 ]. The aim was to maintain the urethral axial integrity and the original urethral length, reducing the hypothetical sexual complications related to the anastomotic urethroplasties (AU) [ 16, 19 – 22 ]. Abouassaly and Angermeier advised against the use of the AU in case of a distal urethral disease in which the urethral transection would further compromise the blood supply [ 18 ]. Furthermore, they stated that, following the urethral transection, the stricture could be longer than the one seen on urethrography and it could cause difficulty in performing the AU with an increased risk of complications. Conversely, the ventral urethral opening allows choosing the adequate solution after the evaluation of the stricture and its length [ 18 ].
In this study we reviewed our results according to the factors that can potentially influence the success rate of the urethroplasties: stricture aetiology, patient age, and prior urethrotomy or urethroplasty proved not to have statistically significant impact on the results, whilst success rate decreased with stricture length > 4 cm.
The main weakness of this study is being retrospective and not prospective. Our population could not be considered homogeneous with regard to the number of patients, stricture etiology and characteristics, patient’s characteristics, and surgeon’s preference. This could bias our statistical analysis. Nevertheless, our study clearly demonstrated that BM graft through ventral urethrotomy access is a versatile technique which could be used for dorsal, ventral or combined dorsal and ventral grafting with comparable success rate.
In graft bulbar urethroplasties, the ventral urethrotomy approach appears simple to perform and versatile because it allows a better visualization of the urethral plate and it enables any of the 3 different solutions: dorsal, ventral, or dorsal plus ventral graft augmentation. The dorsal or ventral grafting is performed according to the stricture characteristics and site within the bulbar urethra. The double dorsal plus ventral graft is useful in tight strictures in which a single graft augmentation is insufficient. Using the ventral approach, all 3 grafting techniques showed a comparable success rate which decreased with the increase of stricture length.