title: Sensitivity of digital abdominal radiography for the detection of ureter stones by stone size and location.
abstract: OBJECTIVE
  To assess the sensitivity of digital abdominal radiography in the detection of ureteral stones by stone size and location.
  
  
  METHODS
  We retrospectively reviewed the digital abdominal radiography of 163 patients for the detection of ureteral stones. Each ureteral stone was confirmed by unenhanced computed tomography (CT) in the emergency department between January and December, 2009. Stone location was defined as proximal or distal by the level where the ureter crossed anterior to iliac vessels, and the stone size was defined as small if smaller than 5 mm and large if larger than 5 mm on unenhanced CT. The interpretation of digital abdominal radiography was classified as visible, invisible, or equivocal.
  
  
  RESULTS
  In 163 ureteral stones, 77 stones (47.2%) were in the proximal ureter and 86 stones (52.8%) were in the distal ureter. The mean (SD) size of the ureteral stones was 3.4 (1.7) mm (range, 1-9 mm). Overall sensitivity of digital radiography for ureteral stones was 29.4%. The sensitivity of digital radiography for the proximal ureteral stones was 37.7% and that for the distal ureteral stones was 22.1% (P < 0.05). The sensitivity of digital radiography for small ureteral stones was 23.6% and that for large ureteral stones was 50.0% (P < 0.05). As a group, the sensitivity of digital radiography for large proximal ureteral stones was the highest sensitivity-72.2%-in all groups (P < 0.05).
  
  
  CONCLUSIONS
  Digital abdominal radiography is useful in detecting large proximal ureteral stones.
authors.affiliation: Department of Radiology, Konkuk University Medical Center, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea. radsijung@kuh.ac.kr
authors.forename: Sung Ii
authors.initials: SI
authors.lastname: Jung
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Kim
authors.forename: Hee Sun
authors.initials: HS
authors.lastname: Park
authors.forename: Hae Jeong
authors.initials: HJ
authors.lastname: Jeon
authors.forename: Hyoung Keun
authors.initials: HK
authors.lastname: Park
authors.forename: Sung Hyun
authors.initials: SH
authors.lastname: Paick
authors.forename: Hyeong Gon
authors.initials: HG
authors.lastname: Kim
authors.forename: Yong Soo
authors.initials: YS
authors.lastname: Lho
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011860:Radiography, Abdominal / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D014514:Ureteral Calculi / Q000000981:diagnostic imaging*