Extraperitoneal Pelvic laparoscopic disconnection of accessory urethra from normal urethra in a case of urethral duplication.

We report an extraperitoneal pelvic laparoscopic approach to disconnect accessory urethra from normal urethra in complete urethral duplication. First stage consisted of chordee correction, partial excision of the accessory urethra and glansplasty. In the second stage the remaining accessory urethra was disconnected from the normal urethra through a pre-peritoneal minimal access approach to the retropubic space. The remaining distal mucosa was ablated using monopolar cautery.

INTRODUCTION

Urethral duplications are rare. Treatment involves excision of the accessory urethra usually through a suprapubic open approach. We report a novel use of extra peritoneal pelvic laparoscopic approach to disconnect accessory urethra from normal urethra in complete urethral duplication.

CASE REPORT

A 10-year-old boy presented with stress incontinence, splaying of urinary stream, and dorsal curvature of the penis. He had an intact foreskin, which, when retracted, revealed a dorsally grooved glans with two meati: one at the tip and the other smaller one at the corona. The prepuce itself was reverse aligned with the frenulum being dorsal, as in epispadias. A catheter could be passed independently through both meati into the bladder. Kidneys and the bladder were not palpable. He passed urine from both meati. Pelvic X ray, ultrasound for kidneys and the blood biochemistry were normal. Complete urethral duplication was the diagnosis.

Surgical treatment

First surgery: Cystoscopy, correction of chordee, repair of glans, rearrangement of foreskin and partial excision of the dorsal urethra. On cystoscopy, the ventral urethra, bladder neck and posterior urethra were normal. A tube passed through the dorsal urethra was seen entering the ventral urethra at the posterior urethra just opposite the veru. Penis was degloved and chordee corrected by ventral Nesbitt. The dorsal accessory urethra was partially excised in the distal shaft and glans repaired to achieve a conical glans with normal coronal collar. The remaining stump of the dorsal urethra was fixed to the shaft skin proximally. The skin was re-arranged to give a circumcised appearance [Figure 1]. Post-operatively he passed urine through both the meati but finger occlusion of the dorsal meatus produced one stream through the normal meatus.

Figure 1

Appearance after the first surgery. Note the repaired glans and the epispadic accessory meatus. Chordee has been corrected

Second surgery performed after 1 year: Through a suprapubic 10 mm port the prevesical space was developed with finger dissection and CO2 insufflation. Two 5 mm ports were inserted as shown in Figure 2a (inset). In the space of Retzius the accessory urethra was identified as it entered the normal urethra at the prostate. The normal urethra was safeguarded by a transurethral catheter. The accessory urethra was severed from the normal urethra using bipolar cautery and scissors [Figure 2a]. A drain was left through the left port site. The ports were removed and the linea alba repaired. The distal stump of the accessory urethra was obliterated by cautery ablation of the mucosa with monopolar electrode passed through the meatus [Figure 2b]. The drain and catheter were removed on 3rd and 10th days, respectively. He passed urine through a single stream and his cosmetic appearance was satisfactory. He is well in 3 year follow up with maintained upper tracts.

Figure 2a

Schematic diagram showing laparoscopic pre peritoneal dissection. Inset shows port placement

Figure 2b

Schematic diagram showing mucosal excision of the distal portion of the accessory urethra

DISCUSSION

Urethral duplications usually occur as an isolated deformity in males, the two urethra lying one behind the other in a sagittal plane. Usually the normally placed ventral urethra is more functional and contains the sphincter mechanism and verumontanum.[12] The accessory urethra nearly always lies dorsal. The classification is variable. Our case had an incomplete epispadic sagittal duplication as per William's classification. However, as per Effmann classification it falls into complete patent duplication Type II (A2).[3]

Surgery to excise the accessory urethra has traditionally involved a combined suprapubic and penile approach to deal with the proximal end and the distal end, respectively. The key step is suprapubic disconnection of the accessory urethra from the good ventral urethra through dissection in the retropubic space.[24] This is technically difficult due to limited space, and risk of venous bleeding from a rich prostatic venous plexus, and carries a risk of damage to the normal urethra, sphincter mechanism and the nerves.[2] We used cautery ablation of the mucosa of the distal most portion. Complete excision of the entire tract was another option. However, it would have been a major undertaking considering the length of the tract and its course between the corpora cavernosa. It would have been technically difficult to reach under the pubic bone to completely excise the distal portion. We used low current settings to ablate only the mucosa. Admittedly there is a risk of scarring with potential for chordee. However, the child has remained well in 3 year follow up. Further follow up is intended to pick up late complications.

The laparoscopic pre-peritoneal approach has been used in adults for excision of benign prostatic enlargement[56] and in partial cystectomy for bladder pheochromocytoma.[7] The reported advantages are minimal bleeding, a reduced transfusion rate, shorter hospitalization, reduced morbidity and faster recovery. In children retroperitoneoscopy has been used for pyeloplasty and other renal surgeries. However, the pre-peritoneal laparoscopic approach for disconnection of accessory urethra has not been described in children to the best of our knowledge. The advantages seem to be clear in that the dissection is easy and precise. Insufflations of gas then result in pressure dissection which creates more space to insert working ports. The visualization of accessory and the main urethra is easy as the view is magnified, free from bleeding and well “retracted”. We have used bipolar cautery and scissors to divide the connection. The stump was left opened. Since this is probably the first case report of such a procedure in urethral duplication, there is no available data in the literature about dealing with the stump. However, there is now sizable experience with laparoscopic pull thru for anorectal malformations with several authors[89] leaving the stump of rectourethral fistula open with no ill effects. Transfixation, suture closure and closure by an endo-loop are other options. Identification of the good urethra was a key safety step. In case of difficulty we had contemplated using a simultaneous cystoscopy through the normal urethra. The light of the telescope would have guided us. However, it was not necessary.