Etiology

Understanding the anatomy of the neophallic urethra is paramount in managing complications. The urethra is divided into five segments from proximal to distal as follows: native (female) urethra, fixed urethra, anastomotic urethra, phallic urethra, and meatus ( Fig. 18.1A ). The fixed urethra is formed after lengthening of native urethra using local vaginal or labial flaps, regional flaps, and skin or mucosal grafts. The anastomotic urethra is the portion where the fixed urethra and phallic urethra are connected. The phallic urethra is constructed using prelamination, or tube-in-tube techniques. The anastomotic urethra is the most common site of urethral stricture.

A, The urethral anatomy of the neophallus in female-to-male patients is divided into five segments: native, fixed urethra, anastomotic urethra, phallic urethra, and meatus. B, Patient with meatal stenosis after phalloplasty. C, Patient with anastomotic stenosis who underwent creation of urethrostomy at the junction of the phallic and fixed urethra.

The rate of urethral stricture after phalloplasty is reported to be from 25% to 58%. Urethral stricture occurs in the anastomotic urethra in 41%, phallic urethra in 28%, meatus in 15%, fixed urethra in 13%, and multifocal in 8%. The most common etiologic factor is ischemia. At the level of the meatus, contracture of neourethral tissue and neophallic skin can cause meatal stenosis ( Fig. 18.1B ). One series reported a mean urethral stricture length of 3.6 cm (range 0.5–15 cm).

Urethrocutaneous (UC) fistula is the most common urethral complication from FTM gender confirmation surgery and is reported in 22–75% of radial forearm free flap phalloplasties. Fistulas are usually associated with a urethral stricture and typically occur just proximal to it. Most common locations are the point of urethral anastomoses between the native urethra and fixed urethra, and between the fixed urethra and phallic urethra. The anastomotic point between the fixed urethra and phallic urethra is compromised due to attenuated vasculature of the free flap. The phallic urethra is typically narrower than the fixed urethra as a result of primary construction or contraction, which causes relative obstruction of urinary flow and resulting fistula. Most UC fistulas will require surgical repair.

Diagnosis

Most common symptoms for patients with urethral stricture are obstructive, including weak stream, urinary hesitancy, straining to void, and incomplete emptying. Symptoms of urethral stricture and/or UC fistula may be recurrent urinary tract infection, dysuria, or suprapubic discomfort. Review of any available operative report of the gender confirming surgery will help with understanding of the anatomic reconstruction. Physical examination may reveal palpable scar or induration at the site of stricture. Any signs of cellulitis should be noted and may be a sign of local infection, abscess, or concomitant UC fistula. Fluctuance may be noted in cases of UC fistula or abscess. Suprapubic tenderness or fullness may be signs of urinary retention that are critical to note. Urethral strictures must be repaired as long-standing obstruction may result in chronic infections, sepsis, bladder stones, and renal insufficiency. Diagnostic assessment is done using retrograde urethrogram and/or voiding cystourethrogram to assess the location and length of stricture as well as presence of UC fistula. Examination under anesthesia may be necessary given the complex anatomy. Cystoscopy should be performed in a retrograde fashion as well as antegrade if there is an existing suprapubic tube.

Treatment

If the patient has urinary retention or severe obstructive symptoms, the urine should be diverted. Foley catheter placement generally requires endoscopy and placement of a small-caliber catheter over a wire. Placement of a suprapubic tube may be helpful by resolving the acute clinical problem and as an aid in surgical planning and treatment. The suprapubic tube should be placed away from the vascular anastomosis of the neophallus, which is typically lateral to the neophallus. If the vascular anastomosis is unknown, image-guided placement or open catheter placement may be safer. Placement of a 16Fr or larger suprapubic tube facilitates performing antegrade cystoscopy for assessment of the urethral anatomy at the time of diagnostic evaluation and surgical treatment. For optimal treatment planning, review of prior surgeries and understanding of the vascular anatomy of the existing flap are paramount.

Examination under anesthesia is done with retrograde and antegrade cystoscopy to determine stricture length and location and presence of fistula. Sometimes the neourethra is narrower than the native urethra and is unable to accommodate the 16Fr flexible cystoscope. A flexible ureteroscope may be used in these cases to directly visualize the urethra. Contrast injection through the scope can be used to perform a retrograde urethrogram using fluoroscopy.

Repair of UC fistula involves closure of the fistula and reinforcement using flaps or grafts. The possibility of use of grafts or flaps while performing urethroplasty or fistula repair should be discussed with the patient. More than one stage may be needed for durable repair. Patients should be made aware of the risk of vascular damage and partial or total loss of the neophallus. If the patient does not wish to urinate from the tip of the neophallus, a perineal urethrostomy ( Fig. 18.1C ) is a reasonable option.

General anesthesia is used in these cases with the endotracheal tube taped to the side opposite the proposed site of buccal mucosa graft harvest. The patient is positioned in a low lithotomy position as it provides access to the genitalia, suprapubic area, and bilateral thighs for possible regional flaps. A guidewire is placed through the fistula and visualized via the cystoscope; this aids in dissection of the fistula tract. Stay sutures placed at the edges of the fistula tract help in dissection and excision of the tract. The urethral opening is closed in several nonoverlapping layers. A local or regional fasciocutaneous flap or labial fat pad flap from the neoscrotum may be used for vascular support ( Figs. 18.2A and B ).

A, Fasciocutaneous flap harvested from the patient’s medial thigh for ventral coverage of a urethral defect. B, Fasciocutaneous flap used for coverage and to provide support for ventral buccal mucosa graft.

If the UC fistula is associated with a urethral stricture, it should be repaired at the same time. Options for treatment of urethral stricture include direct vision internal urethrotomy (DVIU), single-stage anastomotic urethroplasty, single-stage substitution urethroplasty, staged urethroplasty, and perineal urethrostomy. Due to the lack of corpus spongiosum and compromised blood supply, urethral dilation and DVIU have an overall failure rate of 88% in this population. However, for strictures of 3 cm or less, it may be a reasonable option. In one study, the success rate of first DVIU was reported to be 44%, with an additional 13% success rate after a second DVIU at a median follow-up of 51 months. More than two endoscopic procedures were not successful.

One-stage anastomotic urethroplasty techniques include nontransecting urethroplasty using the Heineke-Mikulicz principle, excision and primary anastomosis, buccal mucosa graft urethroplasty, or pedicle flap urethroplasty. In a Heineke-Mikulicz nontransecting anastomotic urethroplasty, the stricture is incised vertically and closed horizontally resulting in a wider lumen. Excision and primary anastomotic urethroplasty is done when the strictured segment of the urethra is less than 2–3 cm long. The stricture is excised, healthy ends spatulated, and primary anastomosis done. The success rate of excision and primary anastomotic urethroplasties has been reported to be about 57% in neophallus patients; low success rates are attributed to decreased blood supply and inability to maximally mobilize tissue.

One-stage substitution urethroplasty is performed when the stricture is longer and not amenable to anastomotic repair. Several flaps or grafts have been used including fasciocutaneous flap, bladder mucosa, and buccal mucosa grafts. A dorsal inlay approach is preferred over ventral onlay due to the better vascular bed on the dorsal surface. In traditional native dorsal inlay urethroplasty, the urethra is mobilized circumferentially. However, in neophallic urethroplasty, circumferential mobilization is not recommended as it may compromise the blood supply to that portion of the urethra. Instead, after the urethra is opened, a ventral urethrotomy on the dorsal surface is made and the graft placed on the dorsal surface, followed by closure of the ventral urethrotomy. In the perineal or neoscrotal area, overlapping double-face grafts can be used ( Figs. 18.3A and B ). Dorsal inlay is done as described. In addition, a ventral onlay graft is placed and covered with a labial fat pad from the neoscrotum or a gracilis flap. As in urethroplasty for natal males, buccal mucosa graft is the graft of choice for substitution urethroplasty for two main reasons: (1) presence of pan-laminar vascular plexus and (2) nonkeratinized epithelium used in a wet environment.

A, Neophallus with stricture of the anastomotic urethra. Urethrotomy is made ventrally. B, Buccal mucosa graft is placed ventrally, and a fasciocutaneous flap is moved over for coverage of the graft.

A two-stage substitution urethroplasty may be done for long or recurrent strictures. The urethra is opened ventrally. A buccal mucosa graft is placed to widen the urethral plate ( Figs. 18.4A and B ). Six months later, the urethra is tubularized and the neophallus is closed. This technique has the highest success rate (70%) as reported in a large neophallus urethroplasty study.

A, First-stage urethroplasty using buccal mucosa graft. B, Bolster dressing is placed over the graft for 1 week until the graft takes.

Perineal urethrostomy is another option if the patient does not have a desire to urinate in a standing position. The fixed urethra is opened and approximated to the perineum to expose the native urethral meatus (see Fig. 18.1C ). Despite the approach, stricture recurrence rates remain high at 60%, and multiple procedures may be necessary. Urinary incontinence is not an uncommon problem in these patients. This is due to urine trapping in the fixed and phallic urethra. Lifelong follow-up on bladder function is important due to the high risk of bladder dysfunction given the prevalence and recurrence of urethral strictures.

Etiology

Many FTM patients undergo vaginectomy as a part of their gender confirmation surgery. However, if there is a distal urethral stricture, the back pressure of urine causes urine to leak from the fixed urethra into the obliterated vaginal cavity ( Fig. 18.5A ). Incomplete vaginectomy predisposes to this condition. A collection of fluid in this cavity leads to obstructive symptoms, urinary incontinence, and recurrent urinary tract infections.

A, CT scan showing urine leaking into a cavity that is the remnant of the vagina. B, Image of robotic-assisted laparoscopic excision of the remnant vaginal cavity. C, Appearance of meatus after meatal reconstruction. D, The addition of the robotic technique to the standard perineal approach allows for intraabdominal deep pelvic dissection, helping to identify neighboring structures.

Diagnosis

If a persistent vaginal cavity is present, retrograde urethrogram and voiding cystourethrogram will reveal extravasation from the urethra and filling of a cavity. Examination under anesthesia and cystoscopy will help confirm the findings and aid in surgical planning.

Treatment

When a persistent vaginal cavity is found, it must be completely excised and the remaining space obliterated. The transabdominal robotic-assisted laparoscopic approach has been used to facilitate complete removal of the remaining vaginal epithelium (see Fig. 18.5B ).

Etiology

The urethral meatus can become stenosed in about 15% of neophallus patients due to contraction of skin and the neourethra; blood flow may also be compromised at this point.

Diagnosis

Diagnosis is made by physical examination. Retrograde urethrogram may be done if urethral stricture is suspected in the rest of the neourethra. Alternatively, cystoscopy is done at the time of reconstruction to assure that the rest of the urethra is normal.

Treatment

Meatal stenosis is treated with meatotomy if the rest of the urethra is uninvolved. The patient should be advised that this may result in mild hypospadias. To avoid the appearance of hypospadias, we incise the meatus in a ventral as well as dorsal fashion, excise the dense scar, and spatulate the opening ( Fig. 18.5C ).