To investigate the clinical efficacy of dorsal mosaic surgery with penis free flap for the treatment of anterior urethral stricture after TURP.

We analyzed the clinical data of the patients with anterior urethral stricture after TURP from January 2010 to December 2017 in Yan′an hospital affiliated to Kunming medical university retrospectively. The patients' age ranged from 58 to 75 years, with an average of 64.3 years. The time from TURP to the diagnosis of anterior urethral stricture was 1-12 month, with an average of 3.5 months. 5 cases were urethral stricture at penis segment, 11 cases were urethral stricture at the junction of penis and scrotum, and the length of the narrow urethra was 2-5 cm, with an average of 3.4cm. The average maximum uroflowmetry in preoperative was (5.3±2.7) ml/s.11 cases were treated with regular urethral dilatation and the treatment durable time was more than 6 months, 5 cases were treated with intraurethral incision combined with urethral dilatation(1 or 2 times). 16 cases were not effective after receiving the above treatment, so that all cases were treated with dorsal mosaic surgery with penis free flap. Subarachnoid anesthesia combined with epidural anesthesia, the patient took the supine position.The distal end of urethral stricture was defined by urethral dilator. Incision from the ventral side of the urethra. The length of the incision was extended 0.5 cm based on the length of urethral stricture in urethral angiography.Anatomize the left and right sides of the urethral stricture and longitudinally incision the ventral side of the urethral cavernous body. The length of the incision was extended 0.5 cm to the normal urethral mucosa. The traction line retracts the ventral urethral edge along both sides.The corresponding medial line of the dorsal urethra was incised to the tunica albuginea, and the urethral edge of the dorsal side was separated from the tunica albuginea to form an elliptical region on the tunica albuginea.According to the size of the ellipse, the full thickness of the penis flap was taken, and the size of the flap was beyond the edge of the elliptical area about 0.3 cm.The free flap was covered with the 6-0 absorbable suture on the elliptical area (the skin surface was on the inner side of the urethra), the edge of the free flap was intermittently sutured with the urethral edge of the dorsal side, Multi-needle intermittent sutured flap surface on the corpus cavernosum bed.Using a silicone catheter as the stent tube of the new urethra, the 6-0 absorbable suture closes the ventral side of the incisional urethral sponge.The multi-layered meat film was sutured to prevent leakage of urine, and the fascia and skin were sutured layer by layer. The 5-0 absorbable thread sutures the wound after the foreskin was taken.

The operations were successfully completed. The operation time was 90-120 min, with an average of 102.3 min. The intraoperative blood loss was 10-30 ml. The symptoms of dysuria were relieved in all patients after removal of the catheter at 3 weeks postoperative. 4 weeks after surgery, no signs of urethral stricture were observed in urethrography. And the maximum flow rate was >15 ml/s in 13 cases, while 3 cases was 10-15 ml/s. The mean maximum flow rate in postoperative was [(20.4±7.3) ml/s], which was significantly higher than that in preoperative (t=7.7602, P<0.05). B-ultrasound showed 13 cases without residual urine and 3 cases of residual urine volume <30 ml. All patients had no serious complications such as urinary fistula, urethral diverticulum and extravasation of urine. After 1 year of follow-up, 1 patient was lost to follow up, and none of the remaining15 cases had urethral obstruction due to re-stricture.

Dorsal mosaic surgery with penis free flap could be an effective method and had no obvious complications for the treatment of anterior urethral stricture after TURP.

Urethral stricture; Free flap; Dorsal mosaic; Transurethral resection of the prostate