title: Multidetector computed tomography arteriography in the preoperative assessment of patients with ureteropelvic junction obstruction.
abstract: BACKGROUND
  Nowadays, endoscopic management of ureteropelvic junction (UPJ) obstruction is the treatment of choice. However, in the presence of crossing vessels, the success rate of endoscopic management decreases and the risk of hemorrhagic and vascular complications rises. The purpose of this study is to evaluate patients with UPJ obstruction using contrast enhanced multidetector computed tomography (CT) angiography to aid in surgical planning and management.
  
  
  METHODS
  Between 2001 and 2005, 27 patients (mean age: 43 years; age range: 17-75 years) with UPJ obstruction were studied with multidetector CT angiography. Identification and characterization of crossing vessels was performed with multidirectional images and three-directional reconstructions.
  
  
  RESULTS
  12 patients (44%) were found to have 16 crossing vessels (vessels in contact with the UPJ or within a vicinity of less than 2 mm). Nine of these vessels were arteries and seven were veins. Nine vessels crossed anteriorly, two posteriorly, and one anteromedially. Endopyelotomy was contraindicated in these 12 patients due to the presence of crossing vessels. Eleven out of the 12 patients underwent a pyeloplasty by open surgery or laparoscopy, where the presence of crossing vessels was confirmed. One of the 12 patients did not undergo surgery.
  
  
  CONCLUSIONS
  Multidetector CT angiography permits an adequate preoperative assessment of patients with UPJ obstruction as it is able to identify the presence and location of crossing vessels. Furthermore, it allows to study in detail the anatomy of the renal area and its vascular variants.
authors.affiliation: Department of Radiology, Hospital de la Plana, Ctra. de Vila-real a Borriana KM. 0.5, 12540 Vila-real, Spain. PetraBraun@gmx.de
authors.forename: Petra
authors.initials: P
authors.lastname: Braun
authors.forename: Jose Pamies
authors.initials: JP
authors.lastname: Guilabert
authors.forename: Faaiza
authors.initials: F
authors.lastname: Kazmi
mesh_terms: D000293:Adolescent; D000368:Aged; D000792:Angiography / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D007682:Kidney Pelvis / Q000098:blood supply* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods*; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*; D014517:Ureteral Obstruction / Q000000981:diagnostic imaging* / Q000601:surgery