Bracka Urethroplasty with Buccal Mucosa Graft: Ergonomic Management of Penile Skin Dartos in the First Stage to Facilitate Second-stage Neourethral Coverage.

AIMS: The aim of the study was to report a new technique of ergonomic penile skin-dartos management during buccal mucosa graft (BMG) to provide adequate penile skin-dartos for neourethral coverage at the time of second-stage tubularization.
MATERIALS AND METHODS: Ten proximal hypospadias with severe chordee underwent first-stage surgery with a new technique. An incision along the urethral plate margin and preputial edge was used to split inner prepuce off preputial dartos and penile degloving leaving inner prepuce attached to corona. Urethral plate was divided into the subfascial plane. Penile dartos was bisected in the dorsal midline. Distal half of penile skin-dartos bifurcated and joined to inner preputial edges. Mobilized and lateralized penile skin-dartos was sutured flanking edges of BMG. The second-stage tubularization after 6 months provided neourethral double dartos coverage with eccentric suture lines.
RESULTS: Adequate dartos for neourethral coverage during second-stage tubularization was available in all. Subcoronal urethrocutaneous fistula occurred in one that was repaired.
CONCLUSIONS: Ergonomic management of inner-preputial skin and ventral transfer of penile skin-dartos helps in providing neourethral coverage during subsequent second-stage tubularization to minimize the occurrence of complications. Copyright:

INTRODUCTION

Hypospadias is a very common birth defect with the incidence of 1:250–1:300 birth and incidence is steadily increasing.[12] In the literature, more than 250 procedures have been described for this defect which results from incomplete fusion of urethral folds indicating that none of the surgical techniques described in the past were perfect.[3] Leaving behind the several described techniques in the past, currently the technique of tubularized incised plate (TIP) urethroplasty described by Snodgrass and the technique of 2-stage urethroplasty described by Aivar Bracka are the most commonly performed techniques throughout the world.[4] However, TIP urethroplasty is not universally applicable in all varieties of hypospadias. The limitations are imposed by glans configuration, severity of chordee with quality, and width of the urethral plate.

Two-staged repair described by Aivar Bracka is a simple technical innovation which can be applied to all types of hypospadias including those with severe chordee where division of urethral plate is mandatory for chordee correction. It is also useful in hypospadias with poor urethral plate and poor glans configuration. There are two disadvantages also with Bracka's technique: first, all hypospadias require a two-staged repair, and second, after the placement of buccal mucosa graft (BMG) in the first stage, the second stage is associated with complication of urethrocutaneous fistula in 28%–33%.[56]

The purpose of this communication is to report a new technique of ergonomic penile skin-dartos management at the time of first-stage repair, i.e., placement of BMG, so that plenty of penile dartos and skin is available at the time of second-stage tubularization providing vascularized neourethral coverage. It will also help in placing eccentric suture lines to minimize the occurrence of urethrocutaneous fistula and other complications.

MATERIALS AND METHODS

In the past 2 years, ten patients of hypospadias with severe chordee were selected. The meatal location was penoscrotal in four and proximal penile in six patients. Age at first surgery ranged from 5 to 16 years.

Under general anesthesia, glans was held up with stay sutures. The incision lines were planned parallel to urethral plate on each side from corona to the point little beyond the hypospadiac meatus. The traditional circumcoronal incision was replaced with incision along the preputial edge [Figure 1a]. The marked incision lines were incised beginning at the preputial edge on dorsal side at 10 o'clock and 2 o'clock positions. Inner preputial urothelium was split off the outer preputial skin and dartos up to coronal sulcus [Figure 1b]. Leaving the inner preputial urothelium attached to corona, penile degloving was performed in sub-dartos plane all around, up to the root of penis [Figure 1c]. In all the cases, after penile degloving, the narrow strip of urethral plate acting as bowstring [Figure 1d] had to be divided in subfascial plane to straighten the penis [Figure 1e]. Distal segment of divided urethral plate was undermined up to fossa navicularis. Proximal segment of the divided urethral plate further released off the ventral midline of corpora cavernosa for the complete elimination of chordee. In none of the cases, dorsal plication was required. The midline of fossa navicularis was incised, and bilateral glans wings were raised off exposing the apex of corpora cavernosa [Figure 1f]. The length and width of required graft was mapped from the tip of glans to mobilized hypospadiac meatus at penoscrotal junction. On ventral aspect of exposed corpora cavernosa from 9 o'clock to 3 o'clock position, the width was measured, and sterile paper was cut to shape fitting in the surface area of exposed corpora cavernosa for mapping of buccolabial mucosa graft.

Figure 1

(a) Marking of incision line along the urethral plate that is distally continued along the preputial edge and proximally around urethral meatus, (b) splitting of outer prepuce skin-dartos from inner prepuce, left attached to corona, (c) penile degloving in subdartos plane up to base of penis, (d) after degloving, residual chordee as evidenced by bowstring effect of urethral plate causing bowstring effect, (e) division of urethral plate in subfascial plane for correction of residual chordee, and (f) bilateral glans wings raised in subfascial plane

The strip of buccolabial mucosa graft was harvested from the oral cavity taking following points in considerations: (a) posterior limit did not exceed the tragus, (b) superior limit did not exceed the opening of Stensen's duct, (c) in the gingivobuccal sulcus at least 3 mm of mucosa is left intact, and (d) angle of mouth was not encroached at all.[7]

The saline was infiltrated in the submucosal plane to facilitate graft dissection. After harvesting the buccolabial mucosa graft, it was defatted, and multiple small longitudinal cuts were made in it. In the midline avascular plane, the penile dartos was bisected up to dermal surface of penile skin, but its base to penile skin was not disturbed [Figure 2a]. The inner prepuce, which has already been split off the outer prepuce but left attached to corona, was reposited back on to the dorsal aspect of degloved penis. Through dorsal midline, distal half of penile skin dartos complex was bifurcated, and end point of bifurcated line was sutured to the free edge of inner preputial skin [Figure 2b].

Figure 2

(a) Dorsal penile dartos bisected in avascular midline up to base of penis, leaving penile skin undisturbed, (b) bisecting the distal part of dorsal penile skin dartos and joining it to the midpoint of inner prepuce, (c) buccal mucosa graft placed and quilted over ventral surface of corpora cavernosa and gland bed and flanking of adequate penile dartos over the lateral edge of buccal mucosa graft, (d and e) suturing of adequate penile dartos and penile skin to the lateral edge of graft, (f) showing the adequacy of dartos tissue available for subsequent tubularization

Edges of bisected penile skin-dartos flap were sutured to the edges of inner preputial skin. On ventral side, harvested and defatted buccal mucosa was placed and quilted. Parallel to the lateral edge of placed buccolabial mucosa graft, it is possible to flank it with penile dartos which is already partially mobilized and shifted laterally from the dorsal midline [Figure 2c]. Then on to flanked penile dartos, from corona to root of the scrotum, the edges of penile skin were also sutured [Figure 2d and e]. The resultant effect is that the chordee is completely eliminated, adequate width of graft placed on ventral aspect of corpora cavernosa, availability of plenty of dartos and skin from corona to root of penis lateral to graft edge [Figure 2f], which at the time of subsequent second-stage tubularization, will be readily available for vascularized neourethral coverage with eccentric suture line.

After 6 months, the graft was tubularized and covered with double dartos available throughout the length of graft.

The outcome measurement included (a) graft uptake, (b) recurrent chordee, (c) adequate availability of dartos and skin at the time of second-stage tubularization, and (d) the occurrence of urethrocutaneous fistula after second-stage tubularization.

RESULTS

Graft uptake – Out of ten cases, the graft uptake was excellent in nine patients [Figure 3a]. In one patient because of stitch line infection, the graft uptake was not excellent. However, there was no case of graft loss

Figure 3

(a) Excellent graft uptake, (b) presence of adequate dartos tissue on both the sides of tubularized neourethra, (c) dartos tissue covering the neourethra in a double-breasted manner with eccentric suture lines, (d) the final appearance

Recurrent chordee due to contracture along the junction of BMG and penile skin – There was initial chordee in five patients which subsequently disappeared with topical application of fluticasone ointment. There was no case of persistent chordee at the time of tubularization

Adequate availability of dartos and skin at the time of second-stage tubularization – availability of plenty of dartos strip to provide double dartos cover over the tubularized neourethra with eccentric suture lines, all along the tubularized neourethra [Figure 3b and c]. With this technique of ergonomic penile skin and dartos management, enough dartos was available in all cases to provide vascularized dartos cover over tabularized urethra with eccentric suture lines. The availability of skin was more than necessary with this technique, and it was possible to create median raphe in all the cases

The occurrence of urethrocutaneous fistula after second-stage tubularization – After second-stage tubularization, there was no fistula in nine patients. One patient had subcoronal fistula, which was subsequently repaired. Hence, the overall occurrence of urethrocutaneous fistula was 10%. The overall availability of adjacent dartos tissue enabling 100% neourethral coverage with provision of eccentric suture line was possible in all the patients.

DISCUSSION

Tubularization of buccal mucosa without tension was the first important factor that has been uniformly reported for the healing of second-stage tubularization of urethral plate; the preservation of vascularity of buccolabial mucosa graft at the time of tubularization was the second-most factor, and the third, most important factor reported was neourethral coverage with vascularized dartos flap and eccentric suture line.[8]

Surgical anatomy of hypospadias and its vascularity has been reported by Kureel et al., in 2015.[9] It was pointed out that inner preputial skin receives blood supply from double sources. Apart from vessels, directly from preputial dartos, inner preputial skin also receives blood supply from dorsal penile vessels. Therefore, inner preputial skin even if separated from preputial dartos will always survive because of its double vascularity. Inner preputial skin, once separated and reposited back, will provide skin coverage to distal most part of the penile shaft. The penile dartos has axial pattern of blood supply, and in almost all cases, the axial pattern vessels which come from external pudendal vessels run along 10 o'clock and 2 o'clock position as dorsolateral and dorsomedial branches. If in the dorsal midline, we incise the dartos fascia but leave it attached to penile skin, it is possible to shift the longitudinal strip of dartos with axial pattern blood vessels and place parallel to the margin of BMG, thus providing adequate dartos tissue flanking the edges of BMG on ventral side. It can be subsequently used for double dartos cover with provision of the eccentric suture line [Figure 3b and c].

After the second-stage tubularization, the occurrence of urethrocutaneous fistula is reported as high as 28%.[56] With the application of facts of surgical anatomy and ergonomic management of penile skin-dartos complex preserving axial pattern penile vessels, it has been possible to provide enough vascularized dartos tissue for provision of double dartos coverage with eccentric suture lines. It is because of the combined effect of these factors that in this series, we have only one fistula in cohort of ten cases. Continued study with larger sample size is needed to confirm the efficacy of this procedure. With this procedure, the availability of skin is sufficient so that it is possible to create median raphe on ventral surface enabling the esthetic appearance [Figure 3d].

The limitation of this procedure is that the patient who was earlier operated, with loss of penile skin and dartos with disturbance of the axial pattern of vascularity, this procedure may not be effective.

CONCLUSIONS

The described technique of ergonomic management of inner preputial skin and ventral transfer of penile skin-dartos helps in providing better neourethral coverage at the time of subsequent tubularization and contributes to minimize the occurrence of urethrocutaneous fistula with provision of double dartos flap cover and eccentric suture line.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.