Figure 1. Scar excision and primary anastomosis of spatulated ends is the optimal stricture repair. Note the blue urothelium.
Methylene blue is injected per urethra to stain mucosa, which serves as an aid in suturing.
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In the treatment of urethral stricture disease, overall stricture length dictates the surgical technique to use. Thus, a well-performed
retrograde urethrogram to demonstrate the distal aspect and a voiding cystourethrogram to demonstrate the proximal part of
the stricture are essential to formulate a surgical plan. Cystoscopy and transperineal urethral ultrasound can further complement
the investigations.
When deciding on a choice of surgical method, another key issue is to define the outcome that both the surgeon and patient
desire. In other words, is the goal to create a long-term surgical cure or just temporary management? This article describes
the techniques for managing strictures, emphasizing the goal to provide a long-term, definitive cure.
Internal urethrotomy Internal urethrotomy encompasses all methods of transurethral incision or ablation to open a stricture. Direct visual urethrotomy
by cold knife (as described by Sacshe) with a deep cut at 12 o'clock (generally to 22F) is the traditional method. Others
prefer not to make deep cuts, but rather multiple small radial incisions circumferentially, to open up the urethra.
The goal of cutting a stricture is to have epithelial regrowth before scar re-approximation. At best, the result of urethrotomy
is to create a larger caliber stricture that offers no obstruction to voiding.
Figure 2. Buccal mucosal, which is the primary graft material used today, is shown being de-fatted. Note the graft harvest
size of 2 cm 3 5 cm.
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Pansodoro et al (J Urol 1996; 156:73-5) reported a 58% recurrence rate at 5 years for 142 patients with bulbar strictures
treated by urethrotomy. Second or third attempts at urethrotomy failed in all patients. Of the strictures, 71% were short
and would have been good candidates for definitive anastomotic urethroplasty.
Heyns et al (J Urol 1998; 160:356-8) reported similar results with a 61% recurrence rate in 210 men after 48 months, and 100%
recurrence after a second or third urethrotomy. Therefore, successive urethrotomies or dilatations are merely palliative and
not curative.
Furthermore, single or primary strictures, bulbar location, length <1 cm, and wide caliber are positive factors that predict
the long-term success of urethrotomy (J Urol 1996; 156:73-5).
Urethral dilatation and direct vision urethrotomy with cold knife are popular management techniques for anterior urethral
stricture mainly due to the perception that they are simple procedures that cause little morbidity. Complications can occur,
however, in up to 27% of urethrotomies (Br J Urol 1983; 55:698-700). Serious complications include lumen obliteration, hemorrhage,
sepsis, incontinence, local veno-occlusive erectile dysfunction, glans numbness, priapism (particularly for deep cuts made
at 12 o'clock), and rectal perforation (Urology 1981; 18:467). Reported long-term success rates for laser urethrotomy have
not shown any advantage over cold knife urethrotomy (Urol Int 1995; 55:150-3).
Another reason for the popularity of urethrotomy is that few urologists have continuing experience with urethroplasty surgery.
In a recent nationwide survey of practicing AUA members, 60% of urologists surveyed did not perform any urethroplasties in
the prior year, and only 0.9% performed more than 11 urethroplasties that same year (J Urol 2001; 165:53). Two-thirds of urologists
also believe that the literature supports that urethroplasty should be performed only after repeated failure of urethrotomies
or dilatations. Adhering to a treatment philosophy of a "reconstructive ladder"-a progression from simple to complex surgeries
only after successive failures-is clearly not supported by the published literature.
Figure 3. The buccal graft is ventrally sewn into the defect.
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In general, short bulbar urethral strictures should be treated with a single urethrotomy or dilatation as long as the patient
understands and accepts that long-term success is less than 50%. Others advocate two urethrotomies before proceeding to anastomotic
urethroplasty (Urology 1986; 27:233). However, successive, repeat urethrotomy is to be avoided because of its documented futility,
as well as its potential to reduce the success for future urethroplasty (J Urol 1994; 151:869-74).
Self-expanding stents. To improve the long-term results of urethrotomy, various metallic self-expanding endourethral stents
have been employed. The Urolume stent (American Medical Systems, Minnetonka, MN) is FDA approved for a narrow and specific
role. Indications for use are short, recurrent bulbar strictures in patients <55 years old in whom the urethra can be opened
to >26F. Urolume is contraindicated in strictures of traumatic etiology, the pendulous or membranous urethra, as initial stricture
treatment, or in cases of prior urethroplasty or urethral fistula.
Reported success rates vary greatly, from 43% to 86% (J Urol 1996; 155:904-8). Off-label uses of the Urolume typically produce
high rates of failure and complications.
Urethroplasty Urethroplasty is scar revision surgery. Prior to any urethroplasty, the scar should be stable and no longer contracting. Thus,
the urethra should not be instrumented for 3 months prior to planned surgery. If the patient is unable to void prior to definitive
surgery, a suprapubic tube should be placed.
Techniques for definitive stricture repair include: stricture excision and primary anastomosis, free graft (skin, buccal mucosa,
bladder epithelium), penile or preputial island flap, scrotal island flap, and combined tissue transfer.
Excision and primary anastomosis. Excision of the complete scar and primary anastomosis (EPA) is the optimal method of stricture
repair (figure 1). EPA involves mobilization of the urethra from the penoscrotal junction to proximal bulb, excision of all
scarred tissue, urethral spatulation, and watertight re-approximation.
In general, EPA is appropriate for bulbar urethral strictures up to 3 cm in length (J Urol 1993; 149:505A). Re-approximation
of longer strictures can result in ventral curvature, pain, tension on the anastomosis, and penile foreshortening. Impotent
patients or those with unusually long perineum or penis can often undergo longer anastomotic repairs.
Figure 4. Photo shows a circular fasciocutaneous flap being developed. Note the length of 14 cm for use in reconstruction.
(Photographs courtesy of Steven B. Brandes, MD)
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The success of this procedure is based on the natural elasticity of the urethra, which allows it to be stretched to bridge
the gap after the stricture has been excised. Contemporary series of bulbar anastomotic urethroplasty have demonstrated an
88% to 95% success rate at 5 years (J Urol 2002; 167:1715-9), 87% at 10 years, and 86% at 15 years (Br J Urol 1998; 81:735-7).
Recurrence after EPA is typically the result of inadequate excision of the fibrosis and inadequate urethral mobilization.
Common benign complications include post-void dribbling and reduced force or ejaculate. For complex and/or long strictures,
onlay flap or patch grafting techniques are utilized.
Patch-graft urethroplasty. A graft is a tissue transfer that is dependent on the host blood supply for survival. The process
is called a graft "take" and occurs in two stages: imbibition and inosculation. The primary graft used today is buccal mucosa,
while penile skin and bladder epithelium have fallen into disfavor.
Buccal grafts are highly successful in the bulbar urethra as a patch technique after either dorsal stricturotomy (Barbagli
procedure) or ventral stricturotomy and subsequent spongiosaplasty to cover the graft. Buccal mucosa is easy and quick to
harvest, minimally morbid, and has excellent take (up to 86%), mostly due to a thin lamina propria and thick epithelium (figures
2 and 3).
Dorsal urethrotomy (as described by Barbagli) and grafting has recently become a popular technique to avoid the complications
of diverticula and post-void dribbling. Comparative studies of ventral versus dorsal placement, however, have not demonstrated
differences in troublesome dribbling and significant out-pouchings (BJU Int 2001; 88:385-9). In obese patients with a bulbar
stricture, buccal grafts are particularly useful, since their use can help minimize time in the lithotomy position.
Two-stage urethroplasty. Staged reconstruction is usually reserved for patients who have undergone failed urethroplasties
or those in whom the urethra and local skin are severely scarred. Two-stage reconstruction is also indicated when the stricture
is associated with a fistula or abscess, or when sufficient well-vascularized local skin is lacking for a one-stage reconstruction.
The technique by Schreiter-a modification of the original two-stage urethroplasty by Johansson-uses a ventral urethrotomy
to marsupialize the urethra and a meshed skin graft to the Dartos and urethral edges. After 6 months of graft maturation,
the urethra is tubularizing in standard Thiersch-Duplay fashion.
Penile, scrotal flaps. A flap is a tissue transfer in which the donor blood supply is left intact. The success of a flap is
described as "survival" and has better overall success than grafts.
Penile skin flaps are the mainstay of urethral reconstruction (figure 4). They rely on the rich vascular collaterals within
the tunica Dartos for its blood supply. The anterior lamella of Buck's fascia is elevated to ensure taking the entire Dartos.
The correct planes are relatively avascular.
Island flaps are versatile and can be mobilized to all areas of the anterior urethra. Success rates of 85% to 90% are seen
with onlay flaps where the urethral plate remains intact. Tubularized flaps have a 45% failure rate (J Urol 2001; 165:1131-4).
Depending on the location and the length of the stricture, flaps can be ventral-longitudinal (as described by Orandi, for
pendulous urethra), ventral-transverse (Jordan/Devine, for fossa strictures) or transverse-circumferential (Quartey, McAninch,
or Q-type procedures, for anterior urethra) and rotated to reach the defect. Proper mobilization will not put the flap on
tension or cause penile torsion. The advantages of transverse-circumferential flaps are that they are hairless, can be mobilized
to any area of the anterior urethra, and are long (10 cm to 15 cm). Ventral flaps require less mobilization, but hair is often
present at the proximal aspect.
Scrotal flaps have a role for patients with bulbar strictures in whom time in lithotomy needs to be minimized or in those
in whom other tissues are not available. Care should be taken to choose a non-hair-bearing area. However, scrotal skin flaps
have fallen into disfavor because they are usually difficult to work with, tend to contract, are more prone to sacculation,
and have a unilateral blood supply.
Occasionally, stricture length is such that flap length is insufficient. In these cases, the combination of distal flap and
proximal graft is used.
Summary The management of urethral strictures should not be considered a reconstructive ladder, ie, the use of successive dilatations
and urethrotomies before considering urethroplasty. Rather, the general goal of stricture management should be cure, not simply
temporary management. Urethrotomy can be curative in short strictures (<1 cm) with minimal spongiofibrosis. Urethroplasty
has durable success rates and should be considered the gold standard by which all other methods should be judged.
