title: Computed Tomography-Based Novel Prediction Model for the Outcome of Shockwave Lithotripsy in Proximal Ureteral Stones.
abstract: Computed tomography (CT) is one of the most commonly used diagnostic modalities for urinary stone disease. In this study we developed a CT and clinical parameter-based prediction model for shockwave lithotripsy (SWL) outcome in proximal ureteral stones.
  
  
  
  Data from 223 patients with single proximal ureteral stones treated with SWL between January 2009 and January 2015 were reviewed retrospectively. Clinical parameters including age, sex, body weight, and body mass index (BMI) were analyzed in combination with stone-related CT parameters (stone diameter, height, volume, location, Hounsfield units [HU], stone-to-skin distance [SSD]), and secondary signs (hydronephrosis, perinephric edema, and rim sign). Based on the cutoff values determined by c-statistics, a scoring system for the prediction of SWL outcome was developed.
  
  
  
  The success rate was 65.9% (147/223), and in a univariate analysis body weight, BMI, SSD (vertical, horizontal), HU, stone diameter, height, volume, and all secondary signs were significantly associated with the success of SWL. However, on multivariate analysis only BMI (odds ratio [OR] = 1.322, confidence interval [CI] 1.156, 1.512, p = 0.00), stone diameter (OR = 1.397, CI 1.259, 1.551, p = 0.00), and perinephric edema (grade 0-1 vs 3-4, OR = 2.831, CI 1.032, 7.764, p = 0.043) were independent predictors of SWL success. The prediction model based on the logistic regression analysis was as follows: SWL success = 1/[1 + exp (-10.165 + 0.279 × [BMI] + 0.334 × [diameter] + 1.040 [perinephric edema])], having an area under the curve of 0.881. In the prediction model based on these parameters, scores of 0, 1, 2, and 3 correlated with SWL success rates of 98.5%, 65.7%, 31.4%, and 0%, respectively.
  
  
  
  BMI, stone diameter, and perinephric edema were independent predictors of SWL outcome and a prediction model based on these parameters will facilitate decision-making for SWL in proximal ureteral stones.
authors.affiliation: 1 Department of Urology, College of Medicine, Korea University , Seoul, Korea.
authors.forename: Hong Seok
authors.initials: HS
authors.lastname: Park
authors.affiliation: 2 Department of Urology, Urological Science Institute, Yonsei University College of Medicine , Seoul, Korea.
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Gong
authors.affiliation: 2 Department of Urology, Urological Science Institute, Yonsei University College of Medicine , Seoul, Korea.
authors.forename: Cheol Yong
authors.initials: CY
authors.lastname: Yoon
authors.affiliation: 1 Department of Urology, College of Medicine, Korea University , Seoul, Korea.
authors.forename: Du Geon
authors.initials: du G
authors.lastname: Moon
authors.affiliation: 1 Department of Urology, College of Medicine, Korea University , Seoul, Korea.
authors.forename: Jun
authors.initials: J
authors.lastname: Cheon
authors.affiliation: 2 Department of Urology, Urological Science Institute, Yonsei University College of Medicine , Seoul, Korea.
authors.forename: Young Deuk
authors.initials: YD
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D001835:Body Weight; D000066491:Clinical Decision-Making; D003661:Decision Support Techniques; D004487:Edema / Q000000981:diagnostic imaging / Q000209:etiology; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging / Q000209:etiology; D008096:Lithotripsy / Q000379:methods*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D036542:Tomography, Spiral Computed; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014514:Ureteral Calculi / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy*