MP54-15 STONE HETEROGENEITY INDEX DEFINED AS THE STANDARD DEVIATION OF HOUNSFIELD UNITS ON NON-CONTRAST COMPUTED TOMOGRAPHY IS A NOVEL PREDICTOR FOR SHOCK-WAVE LITHOTRIPSY OUTCOMES IN URETERAL CALCULI

Abstract

You have accessJournal of UrologyStone Disease: Shock Wave Lithotripsy1 Apr 2016MP54-15 STONE HETEROGENEITY INDEX DEFINED AS THE STANDARD DEVIATION OF HOUNSFIELD UNITS ON NON-CONTRAST COMPUTED TOMOGRAPHY IS A NOVEL PREDICTOR FOR SHOCK-WAVE LITHOTRIPSY OUTCOMES IN URETERAL CALCULI Joo Yong Lee, Dong Hyuk Kang, Doo Yong Chung, Jae Heon Kim, Yong Jin Kang, Hae Do Chung, Jong Kyou Kwon, Won Sik Ham, Young Deuk Choi, and Kang Su Cho Joo Yong LeeJoo Yong Lee More articles by this author , Dong Hyuk KangDong Hyuk Kang More articles by this author , Doo Yong ChungDoo Yong Chung More articles by this author , Jae Heon KimJae Heon Kim More articles by this author , Yong Jin KangYong Jin Kang More articles by this author , Hae Do ChungHae Do Chung More articles by this author , Jong Kyou KwonJong Kyou Kwon More articles by this author , Won Sik HamWon Sik Ham More articles by this author , Young Deuk ChoiYoung Deuk Choi More articles by this author , and Kang Su ChoKang Su Cho More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.585AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Variations in morphology and internal structure of urinary calculi may cause differences in stone fragility. Stone heterogeneity index (SHI), a proxy of such variations, was defined as the standard deviation of a Hounsfield unit (HU) on non-contrast computed tomography (NCCT). As shown in Fig. 1, because the composition of urinary stones can vary even though they have a similar MSD, we postulated that a heterogeneous stone may be more fragile than a homogeneous stone. Herein, we defined the stone heterogeneity index (SHI) as the standard deviation of stone density on NCCT, and investigated whether SHI can be a novel predictor for SWL outcomes in patients with ureteral stones. METHODS Medical records were obtained from the consecutive database of 1,519 patients who underwent the first session of SWL for urinary stones between Nov 2005 and Dec 2013. Ultimately, 604 patients with radiopaque ureteral stones were eligible for this study. Stone related variables including stone size, mean stone density (MSD), skin-to-stone distance, and SHI were obtained on NCCT. Patients were classified into the low and high SHI groups using mean SHI and compared. RESULTS One-session success rate in the high SHI group was better than in the low SHI group (74.3% vs. 63.9%, P=0.008). Multivariate logistic regression analyses revealed that smaller stone size (Odds ratio [OR] 0.889, 95% Confidence Interval [CI]: 0.841-0.937, P<0.001), lower MSD (OR 0.995, 95% CI: 0.994-0.996, P<0.001), and higher SHI (OR 1.011, 95% CI: 1.008-1.014, P<0.001) were independent predictors of one-session success. Similarly, stone size, MSD, and SHI also had an independent impact on one-session stone-free status (Table 1). CONCLUSIONS The radiologic heterogeneity of urinary stones or SHI was an independent predictor for SWL success in patients with ureteral calculi and a useful clinical parameter for stone fragility. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e732 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Joo Yong Lee More articles by this author Dong Hyuk Kang More articles by this author Doo Yong Chung More articles by this author Jae Heon Kim More articles by this author Yong Jin Kang More articles by this author Hae Do Chung More articles by this author Jong Kyou Kwon More articles by this author Won Sik Ham More articles by this author Young Deuk Choi More articles by this author Kang Su Cho More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...