LAUSR

Ureteral stricture is a common and challenging disease in urology. Pelvic surgeries, impacted stones and invasive ureteroscopic surgeries contribute to the incidence of ureteral stricture. A variety of treatments have been utilized according to the length and location of strictures. Short ureteral strictures less than 2 cm can be repaired by excision of the stricture segment with primary ureteroureterostomy. Long distal strictures can be treated by ureterovesical reimplantation combined with psoas hitch and/or Boari flap, Boari flap can repair ureter with lesions up to 14 cm in length and Boari flap in addition to the psoas hitch use can provide for an extra length up to more 5 cm to bridge the ureter to bladder. However, long complex strictures of the proximal and mid ureter are still big challenges to urologists, and traditional bowel interposition or renal autotransplantation will come with a high risk of vascular or bowel complications. In the past two decades, several surgical techniques have been used to address these issues. Analogous grafts including ileum and colon reconfigured by Yang-Monti principle, appendix, buccal mucosa and lingual mucosa grafts have been used in the treatment of complex proximal ureteral strictures. Based on the objective success, which defined as improvement in imaging results during the follow-up period, a series of studies reported that a total of 74 cases using ileal tissue (Yang-Monti principle or flap) to repair ureteral stricture reached a success rate of 95.9% (71/74) [1–3]. Steffens et al. [4] reported a 4-year experience of ileal ureteric replacement using the Yang-Monti procedure in 18 patients. During the mean follow-up 4.2 years (0.5–8 years), all of the treated renal units had evidence of improved renal function in ten and stabilization in eight patients. Minor short-term complications, mainly febrile urinary tract infection and paralytic ileus, occurred in 50%, and long-term complications, infections and hernia in 22%. A total of 18 cases using colon tissue (Yang-Monti principle) to treat ureteral strictures, the success rate was 94.4% (17/18). Lazica et al. [5] presented the long-term results of their technique with reconfigured colon segments. 10 of 14 patients received excellent renal function at a median followup of 52.4 months (range 7–136). The advantages are colon can be used in patients without usable small intestine, the proximity of the colon to the ureter in anatomy, the optimal cross-sectional diameter of the graft and less intraperitoneal surgical trauma than with ileal substitutes. Of all 72 cases using appendix tissue (interposition in 54, flap in 18) to repair ureteral strictures, the success rate was 98.6% (71/72) [6]. For adult patients with sufficient appendix, appendiceal onlay ureteroplasty is one of the techniques to repair the right-sided ureteral stricture. Because of the potential high tension, the surgeons should be cautious of using appendiceal ureteroplasty in treatment of the patients with the left-sided ureteral strictures. Since Naude first described buccal mucosal grafts (BMGs) for treatment of ureteric lesions in 1999 [7], 82 cases underwent this novel surgery, and the success rate was 93.9% (77/82). Zhao et al. [8] reported a midterm follow-up result in 19 patients (onlay technique in 15, augmented anastomotic technique in 4) treated with robot-assisted buccal mucosa graft ureteroplasty. The median stricture length was 4.0 cm (range 2.0–8.0). At a median follow-up of 26 months, the overall success rate was 90%. As in the case with BMG ureteroplasty, there are debatable advantages to dorsal versus ventral BMG placement for ureteroplasty. Placement of the graft in a ventral position is easier to perform anastomosis, while dorsal placement has the potential benefit of reducing the diverticular formation. All of these techniques brought a success rate of more than 90%. However, there is no existing consensus on which technique should be used in different types of the upper ureteral strictures. We congratulate the authors for * Bing Li [email protected]