title: Pathologic findings in patients with ureteropelvic junction obstruction and crossing vessels.
abstract: OBJECTIVE
  To define the role of crossing vessels in the pathophysiology of ureteropelvic junction (UPJ) obstruction, we analyzed the relationship between the presence of crossing vessels and UPJ pathologic findings in patients undergoing laparoscopic pyeloplasty. The significance of crossing renal vessels in patients with UPJ obstruction is unclear.
  
  
  METHODS
  We performed a retrospective analysis of 155 consecutive patients undergoing laparoscopic pyeloplasty. Pathologic specimens from the UPJ were evaluated in 95 patients. The presence or absence of crossing vessels was documented intraoperatively. The histopathologic findings allowed for categorization into 5 groups: group 1, normal ureteral tissue; group 2, chronic inflammation; group 3, smooth muscle hypertrophy, group 4, fibrosis; and group 5, smooth muscle atrophy. The pathologic findings between patients with and without crossing vessels were compared.
  
  
  RESULTS
  Overall, crossing vessels were identified in 98 patients (63.2%). Of the 95 cases with specimens retrieved for histologic analysis, 65 had crossing vessels and 30 did not. The most common UPJ histologic finding in patients with crossing vessels was no intrinsic abnormality (43%). In contrast, this was seen in only 10% of patients without a crossing vessel. In the group without crossing vessels, chronic inflammation (40%) was the predominant histologic findings. Patients with a crossing vessel were less likely to have intrinsic histologic pathologic findings (P < .0003).
  
  
  CONCLUSIONS
  Patients with crossing vessels and UPJ obstruction had no histologic abnormalities identified in 43% of cases. This finding implicates crossing vessels in the pathogenesis of select cases of UPJ obstruction and direct mechanical compression as the etiology of obstruction in these individuals.
authors.affiliation: Smith Institute for Urology, North Shore-Long Island Jewish Health System, New Hyde Park, New York 11040, USA. Lrichsto@yahoo.com
authors.forename: Lee
authors.initials: L
authors.lastname: Richstone
authors.forename: Casey A
authors.initials: CA
authors.lastname: Seideman
authors.forename: Ernesto
authors.initials: E
authors.lastname: Reggio
authors.forename: Rachel
authors.initials: R
authors.lastname: Bluebond-Langner
authors.forename: Peter A
authors.initials: PA
authors.lastname: Pinto
authors.forename: Bruce
authors.initials: B
authors.lastname: Trock
authors.forename: Louis R
authors.initials: LR
authors.lastname: Kavoussi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D006801:Humans; D007682:Kidney Pelvis / Q000098:blood supply* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014517:Ureteral Obstruction / Q000473:pathology*; D055815:Young Adult