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Ureteral strictures following ureteroscopic stone treatment.

Background and purpose: Ureteral stricture is a rare, but serious complication following ureteroscopy (URS) for stones. The aim of this study was to investigate how many patients ended up with a ureteral stricture after URS at our hospital and how these were treated. We also wanted to identify potential risk factors for post endoscopic stricture formation. Materials and methods: A retrospective evaluation of 1001 URS for stone treatment at the day-case surgery unit between 2013 - 2018 was performed. Data on pretreatment status, the surgical procedure and follow-up were recorded. Exact χ2 and independent-samples t-tests were used comparing data among those who developed strictures and those who did not. Multiple logistic regression was performed analyzing risk factors for stricture formation. Results: In total, 1001 URS were performed in 725 patients, 289 women and 436 men. Of these, 995 cases were eligible for analysis. At follow-up with computed tomography after 3 months, 28 (3.0%) strictures were identified. Of these, 20 received endourological treatment with balloon dilatation of which 15 (75%) were successful. Definitive treatment in the 13 patients with failed or unattempted endourological treatment included nephrectomy, reconstructive surgery, permanent nephrostomy or observation with no further treatment. In multiple regression analysis, use of access sheath (UAS) (OR 4.6, p = 0.011), ureteral perforation (OR 11.8, p < 0.0001) and surgical time > 60 minutes (OR 5.7, p < 0.005) were found to be risk factors for stricture formation. Conclusion: Ureteral stricture is a rare complication of URS. Balloon dilatation should be the first line of treatment. Use of UAS, perforation and excessive operating time were found to be risk factors for post endoscopic ureteral stricture formation. Special attention to these risk factors should be given to reduce the incidence of ureteral strictures.