MP35-14 A NOVEL PREOPERATIVE SCORING SYSTEM FOR PREDICTING SUCCESSFUL RENAL ACCESS FOR ULTRASOUND-GUIDED PERCUTANEOUS NEPHROLITHOTOMY

Abstract

You have accessJournal of UrologyCME1 Apr 2023MP35-14 A NOVEL PREOPERATIVE SCORING SYSTEM FOR PREDICTING SUCCESSFUL RENAL ACCESS FOR ULTRASOUND-GUIDED PERCUTANEOUS NEPHROLITHOTOMY Ukrit Rompsaithong, Heiko Yang, Wilson Sui, Rei Unno, David Bayne, Justin Ahn, Marshall Stoller, and Thomas Chi Ukrit RompsaithongUkrit Rompsaithong More articles by this author , Heiko YangHeiko Yang More articles by this author , Wilson SuiWilson Sui More articles by this author , Rei UnnoRei Unno More articles by this author , David BayneDavid Bayne More articles by this author , Justin AhnJustin Ahn More articles by this author , Marshall StollerMarshall Stoller More articles by this author , and Thomas ChiThomas Chi More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003269.14AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Renal access remains a challenging but important step in successful percutaneous nephrolithotomy (PCNL). Understanding factors that predict successful access will help operative planning. With ultrasound guidance for renal access being adopted for widespread clinical practice, this study aimed to develop and validate a novel preoperative scoring system for predicting renal access difficulty for ultrasound-guided PCNL. METHODS: We analyzed consecutive patients undergoing ultrasound-guided PCNL from the Registry for Stones of the Kidney and Ureter (ReSKU) between 2015 and 2022. A risk model was created using a randomized data-splitting approach, using 70% for model development and 30% for model validation. Ultrasound-guided access failure was defined as the inability to puncture the renal calyx of choice using ultrasound-only guidance. To create a multivariate model, the preoperative variables were determined using forward selection and modified according to clinical judgment. The predictive scores were created by weighting the coefficients of each significant factor. The total scores were classified into three risk groups according to the prevalence and the correlation of difficult renal access. The final model was validated. RESULTS: Three hundred renal units were used for model development and 90 for validation. Four significant factors were identified in the final model and scored: body mass index ≥40 kg/m2 (2 points), no/mild hydronephrosis (4 points), staghorn (5 points), and diverticular stone (7 points) (Table 1). The total scores were categorized into low (0-4 points), moderate (5-8 points), and high difficulty (9-18 points), with a failure rate of 4.1%, 15.4%, and 50% in each group, respectively. This scoring system had a sensitivity of 78.1% and specificity of 80.7% in predicting failures over the moderate difficulty cut-point. The area under the receiver-operating characteristic (ROC) curve in the final model and the validation group were 85.5% and 87.7%, respectively. CONCLUSIONS: Our novel scoring system may be an effective screening tool to identify difficult cases for ultrasound-guided access. In these patients, we suggest having backup imaging modalities available for alternate means of achieving access. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e474 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ukrit Rompsaithong More articles by this author Heiko Yang More articles by this author Wilson Sui More articles by this author Rei Unno More articles by this author David Bayne More articles by this author Justin Ahn More articles by this author Marshall Stoller More articles by this author Thomas Chi More articles by this author Expand All Advertisement PDF downloadLoading ...