Urethral Complications in Phalloplasty
David J. Ralph
[Abstract] Full Text [PDF]
The majority of complications that occur in female to male gender reassignment surgery relate to the urethra and this is common to all phalloplasty procedures. The common complications include:
- urethral fistulae;
- urethral strictures;
- stone formation;
- urethral diverticula.
The urethra in the pubic phalloplasty is fashioned out of hairless labia majora and vestibular skin. One side is mobilised and incorporated in the phallus and the opposite side forms the perineal (perineum) urethra to gain continuity to the patients’ native urethra.
The fistula rate when the urethra was fashioned in one stage was 95% but this has been reduced in the two stage urethroplasty to 60%. In this technique the fistula is usually located at the junction of the native urethra with the neourethra and this is likely to be caused by an overlap of the suture line.
With this high fistula rate changes have been made to the technique of closure of the perineal urethra. Firstly, a martius fat pad is taken from the labia majora and mobilised to cover the entire suture line so that there is no apposition of subsequent sutures during the three layer closure. Since this has been performed the fistula rate has been drastically reduced.
The other feature that has been changed is that urethral catheters were previously left in situ for approximately three weeks to allow healing to occur and it is the impression that this is unnecessary. Consequently now the phallic urethra is fashioned and once this is stabilised and shown to be patent the perineal urethra is then formed and a urethral stent left in situ for approximately five days with a covering suprapubic catheter.
A urethrogram is then performed at three weeks and this too has reduced the fistual rate. Alternative techniques to prevent fistulae have been the use of an anterior vaginal flap which is mobilised and sutured to the vestibular skin.
This with a combination of the Martius fat pad reduces further suture line apposition and and consequent urethral fistula formation. Urethral fistulae may also occur with the radial forearm flap phalloplasty. This is likely to be due to ischaemia of the urethral skin at the junction of the native and neourethra.
In all phalloplasty techniques, providing there is no distal urethral obstruction, a simple repair with great care to avoid suture apposition and the use of healthy vascular tissue usually result in a successful closure.
Urethral strictures occur commonly in all phalloplasty procedures due to ischaemic necrosis of the tissue that has been used. With the forearm flap phalloplasty the stricture rate depends on the position of the Urethral strip.
The stricture rate is less if the urethra is centrally based over the radial artery and more of a problem when the strip is harvested from the hairless kin of the ulnar border of the forearm. Strictures with this technique may occur anywhere along the pendulous urethra but more commonly at the junction of the skin tube to the perneal neourethra, particularly is spatulation has been inadequate. In the pubic phalloplasty, urethral strictures commonly occur at the meatus. This is due to ischaemic necrosis of the mobilsed labial flap.
The flap is based on the clitoral blood supply and consequently the most distal areas are prone to ischaemia. Strictures in other areas using this technique are rare as the labial and vestibular skin makes an ideal urethral substitute.
Many treatment options have been used to treat these urethral stricutes to include repeated dilation, urethrotomy, meatoplasty and urethroplasty. It is common for patients to perform self meatal dilation in the pubic phalloplasty though it is clear that a longstanding cure using dilation is unlikely.
Other patients will maintain a small urethral stent in the meatus to direct the stream and to prevent restricture. Recurrence after urethrotomy is also the rule and a permanent cure can only be achieved by a formal meatoplasty or urethroplasty depending on the position of the stricture.
It is also important that a minimal number of re-operations be performed as multiple procedures are likely to disfigure the cosmetic appearance of the phallus. Urethroplasties using a split skin graft and pedicled island skin flaps have so far been unsuccessful. Great advances have however been achieved using free grafts of buccal mucosa.
The buccal mucosa is harvested from the inner cheek but for longer flaps extension to the lower lip can be performed. It is important that the graft is thin to increase the chance of being viable and therefore it should be de-fatted before being used. It is an ideal substitute as it used to being permanently wet, unlike the use of skin. It can be used as a patch or tubed over a catheter with spatulations at both ends: however tubed grafts are more likely to develop anastomotic strictures. Many recipient beds have been used. Where there is a meatal stenosis the penis is opened through the original incision and cut down to healthy vascular neourethra.
This scar tissue base seems to have a reasonable vascularity to accept the buccal graft. Where patients have had an absence of the urethra a catheter has been inserted intially, left for three weeks to allow granulation tissue to form and this granulation tissue bed used for a long tubed buccal graft.
Occasionally two segments of buccal graft harvested from both cheeks can be used although at the junction of the two tubes anastomotic stricture may occur. Therefore with longer tubes it may be necessary to harvest the buccal mucosa in one segment extending from one cheek to around the lower lip and on to the other side.
The buccal donor area is closed primarily with catgut and after three weeks the scar is very difficult to see. There is minimal morbidity from the donor site area and patients are recommended to start eating the following day.
Other techniques using buccal mucosa include an onlay. Here the skin can be de-epithelialised to leave the dermal tissue bed with is an excellent recipient of the buccal graft.
After a three month period to allow contraction this area can then be tubed as a second stage.
Stone formation is common if there are large areas of redundant urethra and therefore pooling of urine within these areas. If hair bearing skin has been incorporated into the urethra this will also precipitate secretions to collect and stone/hairball formation. Recurrent urine infections are common when this occurs. Patients also complain of a post micturition dribble, which is common in all patients that have artificial urethras fashioned.
Great advances have now been made with the urethral formation in patients having a phalloplasty procedure. The urethra should be harvested from vascular areas of the body to have a uniform structure to prevent stone formation and spraying at micturition.
Urethral fistulae and strictures will of course continue to occur routinely but the treatment of these has now been revolutionised by the use of buccal mucosa and the careful avoidance of suture line apposition.
anastomosis: a communication between or coalescence of blood vessels; the surgical union of parts and esp. hollow tubular parts anterior adjective 1: relating to or situated near or toward the head or toward the part in headless animals most nearly corresponding to the head 2: situated toward the front of the body.
apposition: the placing of things in juxtaposition or proximity.
buccal: of, relating to, near, involving, or supplying a cheek.
catheter: a tubular medical device for insertion into canals, vessels, passageways, or body cavities usu. to permit injection or withdrawal of fluids or to keep a passage open.
dermis: the sensitive vascular inner mesodermic layer of the skin.
distal: situated away from the point of attachment or origin or a central point: as located away from the center of the body. back
epithelium: a membranous cellular tissue that covers a free surface or lines a tube or cavity of an animal body and serves esp. to enclose and protect the other parts of the body, to produce secretions and excretions, and to function in assimilation. back
fistula: an abnormal passage leading from an abscess or hollow organ to the body surface or from one hollow organ to another and permitting passage of fluids or secretions.
granulation: one of the minute red granules made up of loops of newly formed capillaries that form on a raw surface (as of a wound) and that with fibroblasts are the active agents in the process of healing.
granulation tissue: tissue made up of granulations that temporarily replaces lost tissue in a wound.
ischemia: localized tissue anemia due to obstruction of the inflow of arterial blood junction noun : a place or point of meeting.
meatoplasty: plastic surgery of a meatus.
necrosis: death of living tissue.
patent: affording free passage; being open and unobstructed.
perineal: of or relating to the perineum.
perineum: the area between the anus and the posterior part of the external genitalia esp. in the female.
phalloplasty: plastic surgery of the penis or scrotum back
radial: of, relating to, or situated near the radius or the thumb side of the hand or forearm.
stenosis: a narrowing or constriction of the diameter of a bodily passage or orifice.
stent: a mold formed from a resinous compound and used for holding a surgical graft in place.
stricture: an abnormal narrowing of a bodily passage (as from inflammation, cancer, or the formation of scar tissue) <esophageal ~> : the narrowed part.
suprapubic: situated, occurring, or performed from above the pubis.
urethra: the canal that in most mammals carries off the urine from the bladder and in the male serves also as a genital duct. back
urethrogram: a roentgenogram of the urethra made after injection of a radiopaque substance.
vascular: of, relating to, constituting, or affecting a tube or a system of tubes for the conveyance of a body fluid (as blood or lymph).
vestibule: any of various bodily cavities esp. when serving as or resembling an entrance to some other cavity or space: as the space between the labia minora containing the orifice of the urethra.
Citation: Dr David J. Ralph,1999