title: Evaluation of patients with suspected ureteral calculi using sonography as an initial diagnostic tool: how can we improve diagnostic accuracy?
abstract: OBJECTIVE
  The purpose of this study was to evaluate the usefulness of sonography as an initial diagnostic tool in patients with suspected ureterolithiasis.
  
  
  METHODS
  We performed a prospective study of 318 patients with suspected ureteral stones over a 14-month period. All patients underwent sonography after fasting for 8 hours and bladder filling. If no cause of the flank pain was found by sonography, computed tomography or intravenous urography was performed immediately to confirm the absence of ureteral stones.
  
  
  RESULTS
  We found urolithiasis with sonography in 291 of 296 patients with confirmed urolithiasis. The 5 remaining cases were identified after non-contrast-enhanced computed tomography (n = 3), intravenous urography (n = 1), or the passage of a stone (n = 1, pregnant patient). We detected 313 calculi in the 291 patients with sonography as follows: 307 ureteral calculi in 285 patients, 5 urinary bladder calculi that were probably passed from the ureter in 5 patients, and 1 urethral calculus. The locations of the 313 calculi in the 291 patients with a sonographic diagnosis were as follows: 21 were in the ureteropelvic junction, 96 in the proximal half of the ureter, 69 in the distal half of the ureter, 121 in the ureterovesical junction, 5 in the urinary bladder, and 1 in the urethra. Hydronephrosis was seen in 200 of the 291 patients with calculi identified by sonography (68.7%). Twinkling artifacts helped confirm the presence of tiny calculi in 184 of the 214 calculi (86%).
  
  
  CONCLUSIONS
  Sonography can be used as an initial diagnostic tool in patients with suspected ureterolithiasis.
authors.affiliation: Department of Radiology, Soonchunhyang University Bucheon Hospital, Gyeonggi-do 420-021, Korea. indawn@hanafos.com
authors.forename: Seong Jin
authors.initials: SJ
authors.lastname: Park
authors.forename: Boem Ha
authors.initials: BH
authors.lastname: Yi
authors.forename: Hae Kyung
authors.initials: HK
authors.lastname: Lee
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Gong Jo
authors.initials: GJ
authors.lastname: Kim
authors.forename: Hyun Cheol
authors.initials: HC
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*; D014514:Ureteral Calculi / Q000000981:diagnostic imaging*; D055815:Young Adult