Endourology & Stone Disease(구연) (E-159) 변형된 앙와위 자세의 경피신결석제거술에서 술 전 신천자를 위한 KMP 카테터의 효율성 및 안전성 경북대학교 의과대학 비뇨기과학교실 이상희, 권순오, 박경민, 민경찬, 정재욱, 이준녕, 유은상, 김범수 Introduction Traditionally, percutaneous nephrostomy (PCN) using pig-tail catheter was preferred for a pre-percutaneous nephrolithotomy (PCNL) nephrostomy. However, it can sometimes cause difficult situation for guidewire passage down to ureter and access tract loss can even occur. For this reason, Kumpe Access Catheter (KMP) has been recently used as a pre-PCNL nephrostomy for easier guidewire passage to ureter during tract dilation at our institute. In this study, we aimed to analyze the efficacy and safety of KMP for the surgical outcomes of PCNL and compare with those of PCN. Materials and methods From July 2017 to December 2019, a total of 175 patients underwent modified supine PCNL in a single tertiary center. Patients who underwent bilateral operation, multiple punctures or combined operation were excluded and 93 patients were enrolled in this study. Pre-operative renal access was performed by two radiologists and pre-PCNL nephrostomy catheter was selected by preference of each radiologist (Radiologist A: PCN and Radiologist B: KMP). All patients were divided into 2 groups according to the kind of pre-PCNL nephrostomy catheter and patients’ characteristics and surgical outcomes, including stone-free rate, operation time, radiation exposure time, and complications were compared. Results Of 93 patients, 35 patients underwent PCN and 58 patients underwent KMP insertion for pre-PCNL nephrostomy. Patients’ baseline characteristics were not significantly different between the two groups except the presence ratio of calyectasis. Operation time, stone-free and complication rate were not significantly different between both groups, whereas radiation exposure time was significantly shorter in KMP group. Conclusions Compared to the PCN, KMP insertion as a pre-PCNL nephrostomy showed comparable surgical outcomes and shorter radiation exposure time during modified supine PCNL. This study demonstrated that it is feasible to insert KMP for a pre-PCNL nephrostomy, especially in terms of reducing radiation exposure time during surgery. keywords : percutaneous nephrolithotomy, kumpe access catheter, radiation exposure time