Genitoplasty for Congenital Adrenal Hyperplasia

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CHAPTER 55

INTRODUCTION

Surgical management of the neonate with sexual am- biguity presents one of the most enigmatic and true emergencies in pediatric urology. This pathology re- quires a team approach by the neonatologist, pediatric endocrinologist, psychiatrist and urologist. It is man- datory to identify the genetic sex and the biochemical abnormality quickly, and then to schedule the timing and the type of surgical reconstruction. Surgical management of patients with intersex conditions is aimed to achieve near-normal appearance of the genitalia with good function enabling sexual relations.

Female pseudo-hermaphroditism due to congenital adrenal hyperplasia (CAH) is the most common cause of ambiguous genitalia in newborns. This condition is inherited as an autosomal recessive disorder and is associated in 75% of patients with a life-threat- ening salt-losing metabolic condition. Exposure of the 46XX female fetus to adrenal androgens results in varying degrees of virilization of the external genitalia and the distal vagina, although Müllerian pre- cursors of the internal genitalia, fallopian tubes, uter- us and proximal vagina develop normally in the ab- sence of Müllerian inhibiting substance. The progno- sis of these patients when reconstructed surgically and raised as females is excellent for puberty devel- opment, attainment of normal female characteristics, sexual activity and reproductive capability. Success- ful reconstruction depends on accurate pre-opera- tive recognition of the anatomy while the main inter- est is the location of the vaginal opening into the urogenital sinus and its relations to the pelvic floor and the external sphincter mechanism. That can be achieved by ultrasound, voiding cystourethrography (VCUG), computed tomography (CT) or magnetic resonance imaging (MRI) and panendoscopy. The most common anatomical finding is that caused by the 21-hydroxylase deficiency mainly with moderate to severe virilization of the clitoris with the vaginal opening at the “veru montanum” or just below it.

Feminizing genitoplasty should achieve five main goals: (1) provide an adequate opening for the vagina into the perineum, (2) create a normal-looking, wet introitus, (3) fully separate the vagina from the urinary tract, (4) remove the phallic erectile tissue while preserving the glans with its innervation, sensation and blood supply, and (5) avoid urinary tract compli- cations such as infection or incontinence. To fulfill the above-mentioned requirements, we have to deal

with two main problems: with the enlarged clitoris and with the vagina. This surgical challenge may be approached either separately or as a one-stage procedure. In recent years several techniques of one-stage feminizing genitoplasty have been described [1]. Our technique and experience is based on the principle of the vaginal pull-through, by the complete en bloc mobilization of the urogenital sinus via the perineum, reduction clitoroplasty and reconstruction of the introitus utilizing the mucosal redundant urogenital sinus with the phallic skin.

The issue of timing of the genital reconstruction in any intersex situation is a subject of great debate.

Psychiatrists and medical ethicists have raised the issue of irreversible damage caused by early gender as- signment by parents and doctors before the child reaches gender identity. Fortunately, this debate has very little relevance to our decision in the cases of the 46XX karyotype CAH, since these patients have female gender identity. Until recently, nearly all sur- geons recommended that girls with CAH, especially those with high vaginal communication to the urogenital sinus, should undergo the repair in two stag- es: firstly clitoral reduction performed early in life in order to avoid familial and environmental anxiety, and then vaginoplasty postponed to an older age, in order to avoid vaginal stenosis. This complication of vaginal stenosis can be solved by the techniques described by Passerini-Glazel, Gonzales, Rink and Far- kas, since the phallic, preputial skin and urogenital sinus are used instead of a perineal and other skin flaps. Therefore, the early one-stage operation has the major advantage of using the redundant phallic and preputial skin for reconstruction, especially in those girls who are maximally virilized. This excellent material is discarded and wasted if the clitoral surgery is performed as a separate operation. De Jong and Boemers (1995) advocate one-stage operation as early as neonate. The prenatal hyperstimulation by the maternal and placental estrogens that persists into the first 3–4 weeks of life produces vaginal en- largement by mucosal secretions and vaginal wall hy- pertrophy, facilitating an easier vaginal pull-through.

At present, we prefer to perform the one-stage procedure as described below at the age of 3–4 months.

The preoperative management consists of complete bowel preparation, adequate steroids supple- ment and biochemical stabilization.

Genitoplasty for Congenital

Adrenal Hyperplasia

Amicur Farkas

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Figure 55.1

The initial and integral first step of the operation is panendoscopy. A 10-Fr pediatric cystoscope is used.

The bladder is inspected and the communication of the vagina to the urogenital sinus is located. Once the opening is identified, it is almost always possible to pass the scope into the vaginal cavity. At that point the telescope is removed from the sheath and a 6F sil- icone Foley catheter is introduced into the vagina, through the scope sheath. The balloon is inflated to 2–3 cc. The sheath is pulled back and the catheter is

clamped at the distal end of the urogenital sinus to prevent the balloon from deflating. The distal end of the catheter is cut off to enable complete removal of the sheath. The catheter is then re-clamped at its edge. In some cases where there is a narrow vaginal opening, a Fogarty catheter can be used with the scope inserted only as far as the opening and not into the vaginal cavity. A second 8 to 10F catheter is inserted into the bladder in the conventional manner.

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Figure 55.2

The patient is placed in an exaggerated lithotommy position with the thighs widely spread to maximally expose the perineum. The operation begins with a circumferential skin incision around the enlarged clitoris and around the urogenital sinus orifice. This incision is extended into two vertical incisions on the dorsal and ventral aspects of the clitoris. The ventral

incision extends distally into a Y-shape to join the circumfering incision just below the glans and termi- nates proximally in an inverted wide U-shape perineal flap. This flap is extended to the ischium tube- rositas bilaterally. These incisions provide an excellent exposure of the phallic structures and the whole perineum with the urogenital sinus.

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Chapter 55 Genitoplasty for Congenital Adrenal Hyperplasia 579

Figure 55.1

Figure 55.2

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Figure 55.3a,b

The urogenital sinus is dissected from the corporal bodies of the phallus and detached completely. The dissection is continued using electro-coagulation with a needle shaped electrode between the urogenital sinus and the rectum, which is retracted dorsally.

The plain of dissection is carried on laterally between the urogenital sinus and the crurae of the corpora cavernosa. and continued below the lower rami of the pubic bones until the whole urogenital si-

nus can be freely mobilized en-block and pulled out.

The posterior vaginal wall is then exposed and brought to the perineum without tension. The con- tinuous palpation of the balloon in the vagina en- ables accurate and safe dissection.

The two muco-cutaneous flaps made out of the phallic and preputial skin are completely dissected off the corpora cavernosa and pulled aside.

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Figure 55.4

At this point the clitoroplasty is performed using the technique described by Kogan et al [3]: two suture ligatures are placed at the proximal ends of the previously exposed crurae of the corporal bodies. The incisions in Buck’s fascia are at the ventro-lateral aspect of the phallus, in order to preserve the blood supply and the sensitivity of the glans of the clitoris. The Buck’s fascia is dissected from the erectile tissue, which is again ligated just below the glans and then the whole erectile tissue is removed.

If the glans appears to be too bulky, it should be reduced by removing tissue centrally and leaving as much lateral tissue as possible, as this area is more sensitive. The glans is reconstructed with 6/0 sutures.

Then the glans of the clitoris is placed under the pubic arch and sutured in place with two or three 4/0 absorbable sutures.

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Figure 55.3a,b

Figure 55.4

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Figure 55.5a,b

The posterior aspect of the urogenital sinus is brought tension-free as close as possible to the perineum. The bulbo-cavernous muscles are divided in the midline and retracted laterally, thus exposing the

posterior vaginal wall. The vaginal wall is widely in- cised in its posterior aspect over the balloon and between traction and haemostatic sutures.

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Figure 55.6

Once the posterior vaginal wall is opened, its communication to the urogenital sinus and the urethra can be seen. This communication is closed by inter- rupted 5/0 absorbable sutures from inside the vagina.

The previously inserted Foley catheter in the bladder is protecting the urethra.

An adequate length of the urogenital sinus is pre- served as a tube and sutured just below the clitoral glans to serve as urethra. The redundant part of the urogenital sinus is split in the midline in the dorsal aspect, creating a mucosal plate.

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Figure 55.5a,b

Figure 55.6

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Figure 55.7a, b

The mucosal plate of the dorsally split urogenital sinus is sutured to the two lateral flaps of the phallic and preputial skin previously dissected off the phal-

lus. This will create a wide plate that is mucosal in its centre and its tip, while its lateral parts are made of phallic non-hairy soft and distendable skin.

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Figure 55.7a Figure 55.7b

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Figure 55.8

The muco-cutaneous plate is turned downwards, its mucosal base is sutured to the ventral vaginal wall and its lateral edges to the lateral vaginal wall, enabling a muco-mucosal anastomosis around almost 300° of the vaginal opening. The tip of the previously prepared inverted U-shaped perineal flap is sutured to the posterior dorsal corner of the vagina. The

phallic skin is sutured circumferentially, creating labia majora and labia minora.

A Xeroform packing is placed in the vagina and the wound is covered with a compression dressing.

The compression and the vaginal tampon are removed after 48–72 h. The urethral catheter is left in place for 7 days.

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Figure 55.8

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CONCLUSION

Since 1991, 67 patients underwent one-stage feminizing genitoplasty using the above described technique. In two cases mild anterior rectal wall lacera- tion was observed during the operation, which was sutured primarily without any further complica- tions. Wound infection in the buttock area occurred in three cases, resulting in a hypertrophic scar in one case. One clitoris was totally lost due to inadequate blood supply. Two cases resulted in repeated clito- romegalia due to inadequate androgen suppression.

The cosmetic results are very satisfactory. In the few girls who have already reached puberty, we observed a mucosal wide introitus and no evidence of fibrosis.

None of our patients has so far experienced sexual relations and therefore we do not have any informa- tion regarding difficulties in intercourse, sexual satis- faction, fertility and the psychological aspects of intersexuality.

It is important to emphasize that the technique described is mainly suitable for the majority of the CAH cases with 21-Hydroxylase deficiency and with vaginal communication to the urogenital sinus at the pelvic floor or just below it (at the veru montanum). In the low vaginal insertion, a simple cutback is adequate or the use of a small perineal flap as described by Fortun- off et al. In the rare cases of very high vaginal insertion above the pelvic floor at the bladder neck, the perineal approach might be insufficient. Passerini-Glazel advocated the use of abdominal trans-vesical approach by dividing the bladder wall trans-trigonally. This technique was originally described by Monfort to reach the prostatic utricle. We believe, however, that in such rare complicated cases the posterior transanorectal approach advocated by Peña is the best choice. This technique is described in Chap. 4 of this volume by the master himself.

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SELECTED BIBLIOGRAPHY

1. Farkas A, Chertin B, Hadas-Halpern I (2001) One-stage feminizing genitoplasty: 8 years of experience with 49 cases.

J Urol 165 : 2341–2346

2. Fortunoff S, Lattimer JK, Edson M (1964) Vaginoplasty, technique for female pseudohermaphrodites. Surg Gynecol Obstet 118 : 545–547

3. Kogan SJ, Smey, P, Levitt SB (1983) Subtunical total reduction clitoroplasty, a safe modification of existing techniques. J Urol 130 : 746–748

4. Monfort G (1982) Transvesical approach to utricular cysts.

J Pediatr Surg 17 : 406–408

5. Passerini-Glazel G (1989) A new one-stage procedure for clitorovaginoplasty in severely masculinized female pseudohermaphrodites. J Urol 142 : 565–568

6. Peña A (1997) Total urogenital sinus mobilization: an easier way to repair cloacas. J Pediatr Surg 32 : 263–268