Advances in surgical repair of ureteral injury

Ureteral injury can be classified as iatrogenic or traumatic, which represents a rare but challenging field of reconstructive urology. Due to their close proximity to vital abdominal and pelvic organs, the ureters are highly susceptible to iatrogenic injury, while ureteral injury caused by external trauma is relatively rare. The signs of ureteric injury are difficult to identify initially and often present after a delay. The treatment of ureteral injury, which is depended on the type, location, and degree of injury, the time of diagnosis and the patient's overall clinical condition, ranges from simple endoscopic management to complex surgical reconstruction. And long defect of the ureter presents much greater challenges to urologists. Ureterotomy under endoscopy using laser or cold-knife is available for the treatment of 2-3 cm benign ureteral injuries or strictures. Pyeloplasty is an effective treatment for ureteropelvic junction obstruction and some improved methods showed the possibility of repairing long-segment (10-15 cm) stenosis. Proximal and mid-ureteral injuries or strictures of 2-3 cm long can often be managed by primary ureteroureterostomy. When not feasible due to ureteral defects of longer segment, mobilization of the kidney should be considered, and transureteroureterostomy is alternative if the proximal ureter is of sufficient length. And autotransplantation or nephrectomy is regarded as the last resorts. Most of the injuries or strictures are observed in the distal ureter, below the pelvic brim, and are usually treated with ureteroneocystostomy. A non-refluxing technique together with a ureteral nipple or submucosal tunnel method, is preferable as it minimizes vesico-ureteral reflux and the risk of infection. In order to cover a longer distance, ureteroneocystostomy in combination with a psoas hitch (covering 6-10 cm of defect) or a Boari flap (covering 12-15 cm) is often adopted. Among various ureteral replacement procedures, only intestinal ureteral substitution, which includes ileal ureter, appendiceal interposition and reconfigured colon substitution, has gained wide acceptance when urothelial tissue is insufficient. Ileal ureter can be used to replace the ureter of >15 cm defect and even to replace the entire unbilateral ureter or bilateral ureter. Laparoscopic and robotic-assisted techniques are increasingly being employed for ureteral reconstruction and adopted with encouraging results.