Refinements in Surgery for Complications of Hypospadias

• 13 Dec 2021 11:17:24 AM
• |Pediatic Urology

Dear All,

I am providing a commentary by Hunter Wessels on ‘Refinements in Surgery for Complications of Hypospadias’. I am sure this will be useful in increasing our knowledge.

I hope our pundits will shed more light on this with their experience

With warm Regards,

Venu

Refinements in Surgery for Complications of Hypospadias

Hunter Wessells

Stricture and fistula after childhood hypospadias repair can play out over decades and represent one of the most challenging problems for reconstructive urologists. The original surgical technique is from a different era, creating uncertainty as to the presence or absence of the urethral plate, how skin tubes were created, and whether grafts or flaps were used. Underpinning these questions are fundamental challenges: uncertain vascularization of rearranged tissue; deficiency of shaft skin; persistence of chordee; a meatus that may be difficult to recreate; lack of Spongiosal support for reconstruction; the risk or presence of fistula; Lichen Sclerosus; and the challenges of graft take.

In 2021, two studies were published,^1,2 which provide refinements and an alternative to the most commonly used and most successful approach to hypospadias complications; namely, staged urethroplasty.

The advent and dissemination of staged urethroplasty arose out of the need to create a reliable situation out of an unreliable one. Often the urethra that is strictured or fistulized is removed because it is poorly vascularized and created from unpredictable skin. By laying down oral mucosa grafts onto the tunica albuginea, or occasionally the dartos, one can establish a high probability that the urethral plate will become pliable, will have a reliable blood supply, and can be tubularized without undue tension. In a summary of urethroplasty options and outcomes for hypospadias-associated urethral strictures in adults, Saavedra and Rourke demonstrate that the vast majority of patients with a previous hypospadias repair and a long penile urethral stricture undergo a staged procedure with oral mucosa.³ Only the occasional patient can be offered a single-stage procedure with either oral mucosa or a flap. Thus, the questions that most of us face is whether we 1) need to do the staged procedure, and 2) how can we improve its outcomes.

Usually with a stricture there is little choice but to proceed with staged urethroplasty due to the length and severity of the narrowing. However, Shaw and associates describe the novel use of the Asopa technique in case of penile Urethrocutaneous fistula repair with stricture after hypospadias.² Importantly, although fistula is one reason to use the Asopa technique, this could equally be applied to strictures. The important point with this procedure is that 1) there must be enough of a urethral lumen so that when the urethra is split and lateralized there is still adequate tissue to close ventrally, and 2) that the urethral lumen and tube is sufficiently mobile so it can be lateralized dorsally. In particular, if there is an existent urethral plate from the original hypospadias, with elements of corpus spongiosum, those lateralize effectively. Similarly, a skin tube created from local or pedicled skin flaps will generally split dorsally and lateralize. In contrast, the urethra reconstructed entirely from Buccal Mucosa that has been previously fixed to the tunica albuginea may not lateralize well enough to accommodate the dorsal inlay graft, which is the core of an Asopa repair.

In their limited series, Shaw et al avoided the more extensive staged reconstruction of a strictured fistula while trying to solve the problem of the unreliable local skin flaps, which are the typical approach to an Urethrocutaneous fistula after hypospadias. The default position of proceeding to a staged urethroplasty and removing the strictured fistulised urethra may still be necessary and should be in the armamentarium of the surgeon proceeding down this pathway, particularly if the fistulae are large or long.

Azuma, Horiguchi, and colleagues provided an approach to enhance the success of staged oral mucosa graft urethroplasty.³ Acknowledging that narrowing at the proximal urethrostomy created during first-stage urethroplasty is a problem and challenge that often requires additional grafting (‘stage 1.5’), the authors propose a triangular extension of the Buccal Mucosa in the first stage in order to create a “hinge flap” to be used in the second stage. The principle of the hinge flap is not new. However, the use of the oral mucosa free graft in stage 1 to create hairless healthy tissue to be used as a hinge flap is novel in the area of urethral reconstruction. This is particularly appropriate for failed hypospadias strictures, where there again is limited local skin that has reliable blood supply and is hairless. By extending the graft a centimetre proximal and distal to the urethrostomies (for a mid-penile urethral stricture) or the proximal urethrostomy (for a stricture that extends all the way to the meatus), the surgeon invests some additional oral mucosa to mitigate against potential stomal stenosis, which could become problematic at stage 2.

Using the hinge flaps, the authors were able to avoid an intermediate-stage procedure requiring additional Buccal Mucosa, which had been required in 20% of their patients in an historical control group.

These two papers^2,3 provide very specific solutions for advanced problems; namely, a Urethrocutaneous fistula in the context of a penile urethral stricture after hypospadias reconstruction on the one hand, and stomal stenosis at the proximal (or distal) urethrostomy after first-stage urethroplasty using oral mucosa grafts on the other. One could imagine expanding the use of these approaches. The Asopa technique for penile Urethrocutaneous fistula may be applied to a broader range of urethral strictures after hypospadias surgery. This will require larger case series and careful consideration of the quality and viability of the remnant urethra preserved for the ventral closure. Incorporating the triangular extension onto every oral mucosa graft used in staged urethroplasty will over treat, but conversely may help prevent some of the long-term stricture recurrences which we see years and decades after staged reconstructions. The mainstay of urethral complications of hypospadias surgery remains the staged urethroplasty with oral mucosa grafts. These refinements may reduce the need for such extensive staged procedures in selected individuals and complement and improve the success of the workhorse of reconstructive urologists currently for the remaining majority of patients.

References:

1.       https://link.springer.com/content/pdf/10.1007/s11255-020-02767-6.pdf

2.       https://onlinelibrary.wiley.com/doi/epdf/10.1111/iju.14582 (PDF available)

3.       https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6877363/pdf/cuaj-11-e335.pdf

 

Comments(1)

• 

  PANKAJ JOSHI

  24 Dec 2021 12:17:23 PM

  From Sanjay Kulkarni and Pankaj Joshi 

  
  

  Dear Venugopal Sir,

   

  We sincerely thank you for highlighting the most relevant information of all articles published on complex subjects.

  Hypospadias Cripple, urethral stricture in hypospadias and Fistula after hypospadias surgery are among the most significant and controversial topic on reconstructive urologythat needs to be handled by experts in high volume centers.

   

  We have carefully read the letter by Prof . Venugopal and the articles suggested in.

   

  As per our standard approach, after urethral trauma, we  usually prefer transection of the urethra with direct anastomosis. On the contrary, i

  n hypospadias or any non-traumatic urethral strictures, we prefer to avoid transection. Indeed, those condition usually are not presenting with complete obliteration of the corpus spongiosum and urethral epithelium. Thus, transection may cause irreversible loss of vascularity and native tissue, which cannot be replaced. So the message is DO NOT EXCISE in non-traumatic strictures.

   

  In our practice of a center located in India, we tend to avoid Bracka two stage procedure for hypospadias repair due to the high rates of graft shrinkage and contraction which may reached up to 40%

   

  1) stricture:

  To accomplish this problem, we have progressively shifted to a two-stage procedure where the graft is placed on the second stage. The technique follow the principles of Johanson’s Stage I and Stage II repair. Here, after 6 months from stage I,

  we insert BMG as dorsal inlay and tubularized the urethra.This approach significantly increases our patency rate and completely avoided the risk of graft contracture[1].

  Another option can be to counsel patients to perform vacuum physiotherapy after Bracka stage I and continues moisture of the graft with ointments, as suggested by Djinovic et al[2].

   

   

  2) Fistula:

  A multicenter study conducted among our center and Shaw et all from Washington, described the technique of fistula closure. According to the technique, the first step is to identify the narrow portion of the urethra that is distal to the fistulae and enlarged by using dorsal inlay graft. Secondly, the fistulae can be closed by excising the scarring tissue and re-approximate healthy margins. An algorithm on fistulae after urethral reconstruction management can be found at this link.

   

   

  Taken into account these discussed points, our message is:

  1) We prefer to avoid staged urethroplasty for either penile of bulbar urethral stricture, when possible.

  2) If staged-urethroplasty is the only option, we prefer to insert the buccal mucosa graft during the second stage and tabularize it immediately.

   

   

   

  Reference

   

  [1]​Joshi PM, Barbagli G, Batra V, Surana S, Hamouda A, Sansalone S, et al. A novel composite two-stage urethroplasty for complex penile strictures: A multicenter experience. Indian J Urol 2017;33:155–8. https://doi.org/10.4103/0970-1591.203426.

  [2]​Bandini M, Sekulovic S, Spiridonescu B, Dangi AD, Krishnappa P, Briganti A, et al. Vacuum physiotherapy after first stage buccal mucosa graft (BMG) urethroplasty in children with proximal hypospadias. Int Braz J Urol2020;46:1029–41. https://doi.org/10.1590/S1677-5538.IBJU.2019.0845.