Endourology & Stone Disease(구연) (E-164) 경피신루설치술을 시행한 상태의 상부 요관 결석 환자에 대한 충격파 쇄석술은 성공률에 부정적인 영향을 줄 수 있다 충남대학교 의과대학 비뇨의학교실 나현석, 양승우, 이충렬, 이지용, 박종목, 이재근, 김용, 신주현, 나용길, 임재성, 송기학 Introduction & objectives: Shock wave lithotripsy (SWL) offers an effective and minimally invasive method for treating urinary calculi. In this study we investigated whether the presence of a percutaneous nephrostomy (PCN) has any impact on the stone-free rate in SWL patients with upper ureter stone. Also analyzed the data obtained from patients who underwent SWL to assess the factors influencing the outcome. Materials & Methods: We analyzed a total of 236 patients who underwent SWL for upper ureter stone between 2015 and 2019. We retrospectively reviewed the medical data of these patients and evaluated the possible prognostic features, including patient population characteristics, stone characteristics on a non-contrast computed tomographic image. Results: After propensity score matching, 147 patients were extracted from the total patient cohort. There were no significant differences between PCN and no PCN groups after matching, except for a lower stone free rate in the PCN group (55.1% vs. 74.5%, p=0.018). In univariate analysis, younger age, sex (female), smaller size, lower mean stone density (MSD), and absence of PCN were positive predictors for stone-free in patients who underwent SWL. In multivariate analysis, smaller size, lower MSD, and absence of PCN were positive predictors for stone-free in patients who underwent SWL. Conclusion: Stone volume, MSD and PCN were prognostic factors influencing the outcome of SWL. The results of the current study suggest that the PCN during SWL was a negative predictor of stone free in patients with upper ureter stone. keywords : lithotripsy, percutaneous nephrostomy, urinary calculi