A prospective study was performed on 43 ureteral strictures (22 malignant, 21 benign) from 37 patients treated with retrograde balloon dilation from October 1997 to May 1999. After the stricture segments were dilated, ureteral stents were indwelled uniformly for 3 weeks. Strictures were postoperatively followed up radiographically at 1, 3, 6 and 12 months, and annually thereafter. Success was defined by symptomatic and radiographic improvement. The follow-up periods ranged from 8 to 57 months (mean 41 months).

The success rates of the benign strictures at 12 and 36 months were much higher than those of the malignant strictures (67 and 57% vs., 18 and 14%, p=0.0009). While 56% and 47% of the patients with strictures shorter than 2cm were successful at 12 and 36 months, respectively, none with strictures longer than 2cm were successful at the same follow-up periods (p=0.0002). Of the successful benign cases with a shorter segment at 12 months, 12 out of 14 (86%) showed persistent long-term successes at the 36 months follow-up. Other prognostic factors, such as sex, age, location, disappearance of a waist, dilation time and grade of hydronephrosis, were not found to influence the success rate. A multivariate analysis revealed the etiology and stricture length were the only significant prognostic factors affecting the final outcome (p=0.030 and p=0.0262, respectively, by Cox's proportional hazards model).

In consideration of its minimal invasiveness and acceptable long-term outcome, simple retrograde balloon dilation is an effective treatment modality for benign ureteral stricture with a short segment (≤ or= 2 cm), and a shorter duration of stenting (3-weeks) is viable.