Long-segment urethral stricture disease is a challenge for even the most accomplished reconstructive urological surgeon and the best set of techniques required to repair them has not been adequately established. However, what is generally agreed uponis that in cases where a portion of the strictured urethra is severely diseased and narrowed, complete removal of the segment is a requirement for a successful long-term outcome. In the bulbar urethra, excision of the diseased segment can often be followed by a relatively straightforward, anastomotic urethroplasty, as the urethra is quite elastic in this area [9
]. However, in the pendulous urethraextensive mobilization of the non-diseased urethra after excision is not as simple, as the blood supply distally is less reliable [10
] and anastomotic procedures will usually lead to problems with penile chordee. This makes replacement of the entire excised penile urethral segment a requirement.
Single-stage operations to replace circumferential segments of the urethra have been described before and results have been generally unfavourable. Tubularization of free (buccal/posterior auricular) grafts lead to a nearly 50% short-term re-stricture rate, the cause of the poor results hypothesized to be the unreliable blood supply the healing graft receives at its lateral edges [12
]. Tubularization of fasciocutaneous flaps have equally poor outcomes, despite that these grafts bring with them their own, generally reliable blood supply [1
]. These findings have led many to abandon the single-stage repair when complete segments need to be replaced, and performance of a two-stage repair, originally described by Johanson, is now more commonly performed [3
The principles of the two-stage repair include excision of the diseased tissue and then grafting of the underlying, exposed corpus cavernosum with a free graft, most commonly a BMG. The graft is usually left to heal for 6 months, over which time the blood supply to the graft matures. At the second-stage, the lateral edges of the graft are lifted with its new underlying blood supply, and a tube is rolled. This technique has the advantage of ensuring that the tissue being used to replace the urethral tissue has a reliable blood supply before it is rolled into a tube. This improved blood supply is probably why the two-stage repair has been retrospectively shown in the literature to have superior outcomes for re-stenosis rates, as compared with any previously described one-stage tubularization procedures [3
]. However, the two-stage repair leaves the patient with an open, hypospadiac urethra for at least 6 months, and for many patients, this is unacceptable. Additionally, while the original Johansson technique is described as a two-stage repair, a large percentage of men will ultimately require three or more operations before their definitive urethroplasty [3
In the present study, we describe our experience with single-stage segmental urethral replacement using combined tissue-transfer techniques. This technique has previously been described in a few patients by Morey [14
], and more recently, has been shown to be effective in the paediatric population for complex hypospadias repairs [15
]. We find that there are distinct advantages to this technique vs other single-stage operations. For one, the segment of circumferential neourethra relies on two distinct blood sources during the healing process. The dorsal BMG relies on inosculation from the underlying tunica, which has been shown to be extremely reliable [2
], while the ventral fasciocutaneous flap brings with it its own versatile blood supply. Unlike tabularized single-stage repairs, the healing of the ventral and dorsal aspects of the neourethra are, then, effectively independent of each other. Secondly, both the flap and the BMG can be sutured to the lateral edges of corpora, which gives the replaced segment improved stability as compared with tubularized grafts, and possibly helps prevent contracture of this segment.
The results from our early experience with this technique are encouraging. Initial success was nine of 14 men at moderate-term follow-up and after two patients that initially failed underwent a single endoscopic procedure for short anastomotic strictures, the final success rate was 11 of 14 men (78%). These outcomes are significantly better than our previously reported experience with fasciocutaneous flap tubularization in a similar population of patients, in which success was achieved less than half of the time [1
The single-stage repair we have described is not appropriate in some men that require segmental pendulous urethral replacement. Men with significant lichen sclerosus severely affecting the distal penile skin would not usually be suitable candidates for a fasciocutaneous flap, and therefore, might best be managed in two stages using extragenital skin. This may also be true in hypospadias failures where reliable skin to form the fasciocutaneous flap is often absent. Additionally, in some men with long strictures, a first-stage Johanson procedure performed without the second stage may be their best option. We have found that it is not unusual for men with these severe strictures, especially in those with a history of multiple prior operations, to be completely satisfied with a unobstructed, hypospadiac urethral meatus after the first stage has been performed, and this phenomenon has previously been described [6
]. Therefore, in men that are unwilling to accept treatment failure or the need for additional procedures, a single-stage operation might not be appropriate. Still, we have been very satisfied with this surgical option for a select group of men, and feel it offers a reasonable alternative to the traditional two-stage repair, without compromising overall success rates. This, we believe, is because of its incorporation of a dual-blood supply to the neourethra, although this has not been clinically proven. A prospective trial comparing this type of single-stage operation to a two-stage operation would be feasible and appropriate.
In conclusion, we have shown that single-stage, segmental urethral replacement surgery is possible using the combination of a dorsal onlay BMG and a ventral onlay circular fasciocutaneous flap. This technique incorporates a dual blood supply to the neourethra, which is probably responsible for the favourable outcomes as compared with the historical success rates of single-stage tubularization procedures.