//Penile and bulbar urethroplasty using dorsal onlay techniques
Penile and bulbar urethroplasty using dorsal onlay techniques2017-04-05T18:51:36+00:00

Penile and bulbar urethroplasty using dorsal onlay techniques

 

Uretra, stenosi uretrale

pdf chirurgia uretrale

Authors:
Enzo Palminteri et Al.

Publication:
Atlas of the Urologic Clinics

Volume:
11, 29-41

Centre:
Center for Urethral and Genitalia Reconstructive Surgery, Arezzo, Italy

 

 

The surgical treatment of adult anterior urethral strictures has been a constantly evolving process. Recently, considerable changes have been introduced: the wider use of the buccal mucosa graft and the use of the dorsal onlay approach, also named the Barbagli procedure. Moreover, in penile urethra, the dorsal placement of the graft is now combined by the incision of the urethral plate, as suggested by Snodgrass for childhood hypospadias surgery and its augmentation, as suggested by Bracka, Asopa and Hayes.
Three different techniques are presented:

  • Penile one-stage urethroplasty with urethral plate incision and augmentation using a dorsal buccal mucosa graft;rologiv
  • Bulbar one-stage urethroplasty with urethral plate augmentation using a dorsal buccal mucosa graft;
  • Bulbar one-stage urethroplasty with urethral place replacement using a dorsal buccal mucosa graft.

The developrnent of the dorsal onlay graft urethroplasty

Several studies and experiences have contributed to the development of the dorsal onlay urethroplasty for the treatment of penile and buIbar urethral strictures. In 1979, Devine popularized the use of skin graft techniques in anterior urethral reconstruction. In 1980, Monseur described a new urethroplasty: a wide urethrotomy is made on the dorsal urethral surface, and the opened urethra is sutured to the corpora cavernosa. Regeneration of the dorsal urethral mucosa is obtained, leaving a catheter in pIace for a long periodo In 1995, the authors combined the Devine suggestions with the Monseur technique, and described the dorsal onlay graft urethroplasty: the graft (skin or buccal mucosa) is sutured to the corpora cavernosa, and the urethra, which is opened a!ong its dorsa! surface, is sutured to the lateral edges of the patch. In this technique, the regeneration of the urethral mucosa is facilitated by the presence of the graft, thus considerably reducing the time for urethral regeneration. Moreover, the presence of the dol’sal graft facilitates urethral regeneration without formation of the scar tissue, according to the experimental and clinica! studies by Moore and Weaver. Urethroscopy in the patients who have undergone a dOl’sa! on!ay graft urethrop!asty shows a norma! appearance of the new urethra! mucosa, particularly when the substitute materia! was a bucca! mucosa.

 

The significance

Or anatomy In the buibar urethra, the relationship between the corpus spongiosum tissue and the urethral lumen is different than that noted in the pendulous erethra. In the bulbous area of the urethra, the corpus spongiosum is thicker in the ventral aspect and thinner dorsally (Fig. I). Furthermore, the urethral lumen is located dorsally and not centrally (Fig. 1), and a dorsal incision may be more likely to preserve the residual blood supply to the spongiosum tissue. An adequate neovascularization of the graft is achieved by applying the patch so that it becomes adherent to the corpora cavernosa, whereas spread fixation may decrease the risk of graft contraction. Moreover, the graft is covered by the over1ying corpus spongiosum, and fistula formation or patch necrosis has not yet been reported in the literature.

 

Preoperative considerations

In patients who have undergone repeated and deep internai urethrotomies at 12 o’dock, the urethrallumen may be adherent and firmly fìxed to the tunica albuginea because the 101lgitudillal internai cut involves the urethral mucosa, corpus spongiosum tissue, and the tunica albuginea. The healillg of this kind of urethrotomy, along with the extravasatioll can cause a scar that fuses the urethral mucosa to the tunica albuginea. In these situations, mobilization of ~he corpus spongiosum and the dorsal urethra from the corpora cavernosa may be difficult. In patients with an implanted bulbar urethral stent in piace, it likewise may be difficult to approach and free the dOl’sal urethrallumen. In obese patients, exposure ofthe dorsal aspect ofthe urethra may also not be optimal. Finally, in patients with buibar strictures 10cated more proximal or just to the external distai sphincter, the dorsal approach to the urethra may be particularly difficult. Fig. l.

 

Surgical techniques

Penile one-stage urethroplasty with urethral plate incision and augmentation using a dO/’sal buccal mucosa graft

A circumcoronal incision is made through the foreskin completely degloving the penis. The penile urethra is exposed and the strictured tract is fully opened by a ventral midline incision (Fig. 2). The dorsal urethral wall is longitudinally incised (Fig. 3) to the tunica albuginea of corpora cavernosa. The wings of the dorsal urethral wall are laterally mobilized (Fig. 4). The buccal mucosa graft is sutured and quilted onto the bed of the dorsal urethral incision with interrupted 6-0 sutures, and augmentation of the urethral lumen is obtained (Fig. 5). The ventral urethral wall is closed and tubularized (Figs. 6 and 7). A dartos fasciai f1ap is elevated to cover the urethral suture, and the glans and the penile skin are closed. A silicone catheter 14 Ch is left in piace (Fig. 7) for 3 weeks. This technique has been applied to patients with ischemic penile strictures and to the complex hypospadias patient, in which the urethral plate can be mobilized using a midline incision. The technique is not possible when the dorsal urethral wall is fibrous or hirsute, or in patients with Lichen Sclerosus Balanitis Xerotica Obliterans.

Bulbar one-stage urethroplasty with urethral plate augmentation using a dO/’sal buccal mucosa graft

The patient is placed in a low lithotomy position, and a midline perineoscrotal incision is made. The bulbospongiosus muscles are separated in the midline, and the bulbar urethra is freed for its entire length. The dissection of the urethra from the corpora cavernosa (Fig. 8) begins well distai to the area of the lumen, avoiding the portion of the urethra involved in previous urethrotomies. Using a vessei loop, the urethra is completely mobilized from the corpora
cavernosa and rotated 180 degrees (Fig. 9). l’he strictured portion of the urethrallumen is incised dorsally extending the sticturotomy for 2 cm into the healthy urethra both proximal and distai to stricture (Fig. lO). l’he ovoid-shaped graft is spread fixed and quilted to the overIying tunica albuginea of the corporeal bodies (Fig. Il). Currently, the authors preferentially use buccal mucosa. l’he right epithelial margin of the opened urethra is sutured to the right side of the patch graft (Fig. 12), and the urethra is rotated back to its originaI position (Fig. 12). l’he Ieft urethra1 margin is sutured to the 1eft side of the patch graft and the corporal bodies, and the grafted area is entireIy covered by the corpus spongiosum (Fig. 13). l’he bulbospongiosus muscles are reapproximated over the grafted area, and a small suction drain is placed. An indwelling 4 Ch siiicone catheter is left in pIace for 3 weeks. In the authors’ practice, suprapubic cystostomy is not fe!t to be necessary. The day after surgery, the drain is removed and the patient is discharged from the hospital. Three weeks after surgery, the bladder is filled with contrast medium, the catheter is removed, and a voiding urethrogram is obtained.

Bulbar one-stage urethroplasty with urethral plate replacement using a dorsal buccal mucosa graft

The patient is placed in a !ow lithotomy position, and a midline perineoscrotal incision is made. The bulbospongiosus musc!es are separated, and the bulbar urethra is freed for its entire !ength. The area of the stenosis is identified and carefully marked (Fig. 14). A midline incision is made through the ventral urethral surface, and the damaged epithe!ium and corpus spongiosum are identified and evaluated (Fig. 15). The urethral epithelium is removed, leaving in piace the b!eeding corpus spongiosum on the dorsal urethral surface (Fig. 16). A bucca! mucosa graft is tailored according to the length and width of the damaged epithelium. The graft is sutured to the dorsal urethral surface using 6-0 interrupted stitches and is quilted to the underlying corpus spongiosum and the tissues of the corpora cavernosa (Fig. 17). A 4 Ch silicone catheter is inserted, and the urethra is c!osed using 4-0 interrupted stitches (Fig. 18). The bulbospongiosus musc!es are reapproximated over the corpus spongiosum, and a small suction drain is left in piace for I day. The catheter is left in piace for 4 weeks.
The authors fee! that this kind of urethroplasty is advisable in patients with bulbous urethral stricture associated with false passages into the urethra! epithelium and spongiosum tissues or in patients requiring the complete removal of the urethral epithelium, with its complete replacement with a graft.

 

Summary

The armamentarium of the reconstructive urethral surgeon is continuously evolving and requires the surgeon to be familiar with new concepts and concerns. The great elasticity and handiness of the buccal mucosa may increase the number of new surgical techniques that arrange the graft in originai ways. The dorsal approach to the urethral lumen allows a variety of surgical options that vary according to the stricture site and characteristics or to the surgeon’s preference. Long-term followup will be necessary to establish whether buccal mucosa is superior to penile skin as a urethral substitute and, in the future, it is possible that other materials will be available. The dOl’sal onlay techniques are simple, reliable, and effective over the long term; reproducible in the hands of any surgeon; and do not require extensive training in reconstructive procedures using tissue transfer techniques.

 

Acknowledgment

The authors thank Andrea Gennari, Professor at the Artistic Anatomy Department of the Accademia di Belle Arti, Florence, Italy, who provided the illustrations.

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