title: Prevalence of circumcaval ureters and double caudal vena cava in cats.
abstract: OBJECTIVE
  To determine the prevalence of circumcaval ureters and other caudal vena cava variations in cats and determine whether circumcaval ureters were associated with macroscopic evidence of ureteral obstruction.
  
  
  METHODS
  301 domestic cat cadavers obtained from an animal shelter.
  
  
  METHODS
  All cat cadavers were examined, and anatomic variations of the ureters and caudal vena cava were recorded. In cadavers with a circumcaval ureter, kidney length, width, and height were measured, and the ureters were examined macroscopically to determine whether there was gross evidence of ureteral obstruction in cats with circumcaval ureters.
  
  
  RESULTS
  At least 1 circumcaval ureter was present in 106 of the 301 (35.2%) cats, with a right circumcaval ureter identified in 92 (30.6%) cats, a left circumcaval ureter identified in 4 (1.3%), and bilateral circumcaval ureters identified in 10 (3.3%). Twenty-one (7.0%) cats had a double caudal vena cava, including 2 cats in which the double caudal vena cava was the only anatomic abnormality identified. No sex predilection for anatomic abnormalities was found. Mean right kidney length was significantly greater than mean left kidney length in cats with a right circumcaval ureter.
  
  
  CONCLUSIONS
  Circumcaval ureter was present in approximately a third of cats in this study. Variation in the development of the caudal vena cava is the proposed cause. The clinical relevance of this variation is unknown.
authors.affiliation: Department of Small Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 4B5, Canada.
authors.forename: Régine
authors.initials: R
authors.lastname: Bélanger
authors.forename: Cindy L
authors.initials: CL
authors.lastname: Shmon
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Gilbert
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Linn
mesh_terms: D000818:Animals; D002102:Cadaver; D002415:Cats / Q000002:abnormalities*; D005260:Female; D008297:Male; D015995:Prevalence; D064749:Retrocaval Ureter / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology; D014513:Ureter / Q000002:abnormalities* / Q000473:pathology; D014682:Vena Cava, Inferior / Q000002:abnormalities* / Q000473:pathology