Global epidemiological trends and risk factors of ureteral strictures following ureteroscopic lithotripsy: a comprehensive study based on literature data and machine algorithms

INTRODUCTION: Urolithiasis prevalence and ureteroscopic lithotripsy utilization have increased ureteral strictures' visibility. It is imperative to summarize the global epidemiological trends and investigate risk factors associated with lithotripsy itself. EVIDENCE ACQUISITION: A systematic review of English literature was conducted to assess the incidence of ureteral strictures following lithotripsy across all age groups. Comprehensive analyses, including meta-regression, network meta-analysis, and Joinpoint regression, were used to investigate subgroup incidence. Machine learning algorithms identified influencing factors related to lithotripsy. EVIDENCE SYNTHESIS: This study included 43 studies, estimating an overall ureteral stricture (US) occurrence rate of 1.7% and 2.9% over the past decade, indicating an upward trend. Subgroup analysis showed the lowest postoperative stenosis incidence of 1.4% for flexible combined with semi-rigid ureteroscopy. Laser lithotripsy had a higher incidence (2.4%) than pneumatic lithotripsy (1.7%), with an odds ratio (OR) of 4.61 (95% CI: 2.0-10.6). Middle and proximal segment strictures had higher ORs compared to the distal segment (2.2, 95% CI: 1.1-4.1; 2.0, 95% CI: 1.1-3.5, respectively). Machine learning models indicated that operation time is a significant predictor of postoperative stenosis. Joinpoint regression identified a change point at 45 minutes of surgical time (MPC=2.18, P<0.05), with increased stenosis incidence thereafter. CONCLUSIONS: The prevalence of US post-lithotripsy is increasing. Different endoscope types, lithotripsy methods, and locations show distinct incidence rates. Patients with urinary lithotripsy lasting longer than 45 minutes should be actively evaluated for potential stenosis.