title: Factors that predict spontaneous passage of a small distal ureteral stone <5 mm.
abstract: OBJECTIVE
  We assessed the role of the unenhanced helical computed tomography (UHCT) for prediction of concurrent ureteral lesions associated with small impacted stones presenting in distal ureter.
  
  
  METHODS
  From May 2004 to June 2009, we evaluated 30 cases with impacted distal ureteral stones <5 mm. All of the patients were evaluated with unenhancing UHCT, and the secondary signs on UHCT were graded on a scale of 0 to 3. All of the patients were treated by ureteroscopic pneumatic lithotripsy. Ureteral lesions associated with impacted stones were characterized on the basis of the ureteroscopic findings.
  
  
  RESULTS
  Ureteroscopic procedures showed that impacted distal ureteral stones <5 mm had concurrent ureteral lesions such as severe mucosal edema, strictures, ureteral polyps, or submucosal stones. Long-term stone impaction and the UHCT findings of a higher degree of the tissue rim sign, hydronephrosis, and perinephric fat stranding were associated with a higher likelihood of the presence of underlying ureteral lesions.
  
  
  CONCLUSIONS
  The secondary signs on UHCT such as high degree of tissue rim sign, hydronephrosis, and perinephric fat stranding seem to be useful signs in predicting the presence of concurrent ureteral lesions. In those cases, early intervention might have better outcomes than conservative therapy.
authors.affiliation: Department of Urology, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Eugene
authors.initials: E
authors.lastname: Hwang
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Seung Mo
authors.initials: SM
authors.lastname: Yuk
authors.forename: Chong Koo
authors.initials: CK
authors.lastname: Sul
authors.forename: Jae Sung
authors.initials: JS
authors.lastname: Lim
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012075:Remission, Spontaneous; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014514:Ureteral Calculi / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology*; D014515:Ureteral Diseases / Q000150:complications / Q000000981:diagnostic imaging; D055815:Young Adult