title: An audit of routine grey scale sonograghic imaging for pelviureteric junction obstruction: do they identify lower polar vessels?
abstract: BACKGROUND
  Aberrant lower polar vessels are uncommon causes of pelviureteric junction (PUJ) obstruction. Preoperative identification would help in planning the appropriate procedure. We attempted to determine whether routine investigations would predict crossing lower polar vessels.
  
  
  METHODS
  This was a retrospective study of 20 patients that either had ultrasonographic investigation by a radiologist who was blinded to the aetiology of PUJ obstruction, or underwent minimal access surgery for PUJ obstruction, from 2005 to 2007, in the Birmingham Children's Hospital, UK.
  
  
  RESULTS
  There were 20 patients with PUJ obstruction, 8 were found at operation to have crossing lower polar vessels causing PUJ obstruction. The sonography correctly identified crossing vessels in only one, with a sensitivity of 12.5%, specificity of 66.6%, positive predictive value of 20%, and negative predictive value of 53%.
  
  
  CONCLUSIONS
  Preliminary results showed that none of these investigations could reliably identify lower polar vessels.
authors.affiliation: Departments of Paediatric Urology & Radiology, Diana Princess of Wales Hospital, Birmingham, UK.
authors.forename: G Krishna
authors.initials: GK
authors.lastname: Kumar
authors.forename: Stephen
authors.initials: S
authors.lastname: Chapman
authors.forename: Harish
authors.initials: H
authors.lastname: Chandran
mesh_terms: D000293:Adolescent; D002648:Child; D054869:Clinical Audit; D006776:Hospitals, Pediatric; D006801:Humans; D007682:Kidney Pelvis / Q000098:blood supply* / Q000000981:diagnostic imaging*; D008297:Male; D019060:Minimally Invasive Surgical Procedures; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018615:Ultrasonography, Doppler, Color / Q000379:methods; D006113:United Kingdom; D014513:Ureter / Q000098:blood supply / Q000000981:diagnostic imaging*; D014517:Ureteral Obstruction / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery