Gender-affirming vaginoplasty is a reconstructive surgery for people assigned male sex at birth who have gender dysphoria. The goal is to create a natural-appearing vulva as well as a functional vaginal canal of adequate depth and width. Dissection of the neovaginal space is the most challenging step, with risk of injury to neighboring structures. Once the space is developed, the surgeon then lines the space with graft or flap tissue to create the neovagina.

Canal Dissection

Approaches to dissect the neovaginal space broadly follow established prostatectomy approaches: perineal or robotic.

Perineal Approach

The perineal approach mirrors the Young technique for perineal prostatectomy, beginning beneath the bulb of the urethra.¹ It continues above the perineal body and through the rectourethralis muscle. The bulbourethral glands, although variable, are a useful landmark (fig. 1). We find a Lowsley retractor to be helpful in identifying and aiding dissection on to the prostate, as well as helping identify and avoiding the external urinary sphincter. Frequent rectal examinations are imperative to guide the direction of the dissection and avoid injury to the rectum. Once it is certain that the rectum has been safely dissected down from the apex of the prostate, the dissection passes through the ventral rectal fascia and exposes the body of the prostate. The puborectalis muscles are partially divided to allow sufficient width. Blunt dissection from this point develops the space up to the peritoneal reflection, with neovaginal canal depth typically 12 to 14 cm.

Figure 1. During perineal dissection of vaginal canal, important landmarks include bulbourethral glands (B), external urinary sphincter (S) and apex of prostate (P).

Robotic Approach

An alternative method uses robotic assistance to dissect from an intraperitoneal approach as a perineal surgeon simultaneously begins a superficial dissection beneath the bulb of the urethra.² Use of the da Vinci® single port robot facilitates simultaneous abdominoperineal surgery, although the canal dissection can also be achieved using Si™ or Xi™ system. The canal dissection begins by incising the peritoneum under the vas deferens and is carried inferiorly under the seminal vesicles, through Denonvilliers’ fascia, to develop the potential space between the rectum and the prostate, widening levator ani muscles, until it meets with the perineal dissection. A robotic approach can be used for primary or revision canal construction and is especially advantageous for revisions where significant depth or even the entire vaginal canal is lost after prior perineal approach vaginoplasty. Postoperative mean neovaginal depth ranges from 13 to 14 cm.³

Lining the Neovaginal Canal

The “penile inversion” technique uses the penile skin tube, dissected free from the deep structures of the penis, to help line the neovaginal space. In our experience, most patients will need additional tissue to fully cover the space, ie a graft of scrotal skin not needed for vulvar construction. Occasionally patients may require an additional extragenital skin graft. In the robotic approach, peritoneal flaps from the posterior aspect of the bladder and pararectal fossa bilaterally can be used to create the majority of the neovaginal canal, an excellent option for patients with limited genital skin (fig. 2).² Lastly, although more common with revision surgeries, ileum or colon may instead be used, with the inherent risks of intestinal surgery, mucous production and possibly visible intestinal mucosa at the introitus.⁴

Figure 2. Laparoscopic view shows boundaries (ureter and vas deferens) of canal dissection during robotic approach. Composites of anterior peritoneal flap (posterior bladder wall) and posterior peritoneal flap (pararectal fossa) are also highlighted. Photography courtesy of Dr. Lee Zhao, New York University.

Complications

The anorectal junction is densely adherent at the apex of the prostate, increasing the risk of injury to the urinary sphincter and rectum. Reported rates of urinary incontinence are low but are probably understudied.⁵ We do not offer neovaginal canal dissection when someone has had prior treatment for prostate cancer due to the increased risk of injury to the rectum and urinary sphincter.⁶ Rectal injury is rare but can lead to rectovaginal fistulas, which are very difficult to treat.⁷ Meticulous hemostasis is crucial to avoid hematoma formation, which can cause skin graft failure.⁸ Robot-assisted peritoneal flap vaginoplasty carries risks of injury to intra-abdominal structures similar to robotic prostatectomy, in addition to rare peritoneal flap separation.³ Other postoperative complications such as wound separation, granulation tissue and urinary infections may occur and are managed conservatively.

Regardless of canal technique, patients must perform regular dilation of the neovaginal canal after surgery to prevent wound contraction from causing stenosis.⁸ Neovaginal stenosis can lead to loss of function and entrapment of skin debris, which may be prone to infection. In our experience, stenosis occurs most commonly at the passage through the pelvic floor, but may also occur starting from the apex of the vagina. Pelvic floor physical therapy may be beneficial both preoperatively and postoperatively.⁹

Conclusions

Gender-affirming neovaginal canal creation is a challenging surgery that requires extensive knowledge of genitourinary anatomy and function, as well as reconstructive techniques. Urologists are uniquely positioned to lead in this rapidly growing field of surgery.