title: Cold-knife endoureterotomy for nonmalignant ureterointestinal anastomotic strictures.
abstract: OBJECTIVE
  To evaluate the long-term results of cold-knife incision (CNI) of nonmalignant ureterointestinal anastomosis strictures (UASs) after urinary diversion in a consecutive series of patients.
  
  
  METHODS
  Since 1994, we have evaluated retrospectively 40 patients with 43 UASs, who were primarily treated with CNI (group 1). Six patients from group 1 with 7 UASs who failed primary CNI comprised group 2. After placement of an 8F nephrostomy tube, a 0.035-inch guidewire bypassed the stricture in an antegrade fashion under guidance of a centrally opened ureteral catheter (5F). A wire-mounted cold-knife was pulled through the strictured area in retrograde fashion under fluoroscopic control. Postoperatively, an 8 to 12F stent was left indwelling for 6 to 12 weeks. Successful treatment was defined as radiographic and scintigraphic resolution of obstruction and symptomatic relief.
  
  
  RESULTS
  In group 1, after removal of the stent, the ureteroenteric area remained patent in 26 (60.5%) of 43 UASs during a follow-up period of 38.8 months (range 12 to 85). The success rate at 1, 2, and 3 years was 86%, 67.8%, and 60.5%, respectively. In group 2, no success occurred. The diameter and length of the stricture, kidney function, hydronephrosis grade, presence of urinary infection at presentation, past CNI or radiotherapy, number of incisions with the cold-knife, and premature appearance of the anastomosis stricture were statistically significant influences on the outcome (P <0.05). Considering only the patients (n = 8) with the most favorable predictive factors (interval to stricture formation 12 months or longer, stricture length 1.5 cm or less, and hydronephrosis grade I-II), the success rate was 100%. No complications were observed.
  
  
  CONCLUSIONS
  CNI is an effective and minimally invasive treatment for primary UASs, providing durable results compared with other modalities used for endoureterotomy, and should be considered as an initial approach. The selection of patients with the most favorable prognostic factors leads to excellent results. As a secondary procedure, CNI was not successful.
authors.affiliation: Department of Urology, Krankenhaus Nordwest Teaching Hospital of Johann-Wolfgang-Goethe-University Frankfurt, Frankfurt/Main, Germany.
authors.forename: Vassilis
authors.initials: V
authors.lastname: Poulakis
authors.forename: Ulrich
authors.initials: U
authors.lastname: Witzsch
authors.forename: Rachelle
authors.initials: R
authors.lastname: De Vries
authors.forename: Eduard
authors.initials: E
authors.lastname: Becht
mesh_terms: D000368:Aged; D000714:Anastomosis, Surgical / Q000009:adverse effects*; D003251:Constriction, Pathologic / Q000209:etiology / Q000601:surgery*; D003452:Cryosurgery; D005260:Female; D006801:Humans; D007410:Intestinal Diseases / Q000209:etiology / Q000601:surgery*; D007422:Intestines / Q000601:surgery; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014513:Ureter / Q000601:surgery*; D014517:Ureteral Obstruction / Q000209:etiology / Q000601:surgery*; D018666:Ureteroscopy / Q000379:methods*; D014547:Urinary Diversion / Q000009:adverse effects* / Q000379:methods