title: Venous variants and anomalies on routine abdominal multi-detector row CT.
abstract: OBJECTIVE
  This study aims to determine the types and prevalence rates of anatomic variations of the hepatic veins, portal vein, inferior vena cava and renal veins, and to establish statistical correlations between various anomalies and frequency differences between male and female using multi-detector row computed tomography (CT).
  
  
  METHODS
  One thousand one hundred and twenty patients (588 men, 532 women) were evaluated with routine abdominal CT. Frequencies of different variants were noted and compared, and correlations between three categories of variation were tested.
  
  
  RESULTS
  In total, 1261 abdominal vein variants and anomalies were identified in 756 (67.5%) of 1120 patients. Six hundred and forty-two hepatic vein variants were detected in 468 (41.8%) patients. One or more inferior right hepatic veins were identified in 356 (31.8%) individuals, and tributary hepatic veins were detected in 147 (13.1%) patients. Portal vein variations and anomalies were observed in 307 (27.4%) cases. The most frequent of these was trifurcation (139 patients, 12.4%). A total of 311 inferior vena cava and renal vein variants were identified in 258 (23%) cases. Six patients (0.5%) exhibited inferior vena cava anomalies, 62 (5.5%) had circumaortic renal veins, 53 (4.7%) had retroaortic renal veins, and 210 (18.8%) had multiple renal veins.
  
  
  CONCLUSIONS
  The prevalence of abdominal vein variations is high, and routine abdominal CT demonstrates these abnormalities very well. The data suggest that hepatic vein variants and multiple right renal veins are more frequent in women than in men, and that hepatic vein variation is correlated with portal vein variation.
authors.affiliation: Başkent University, School of Medicine, Department of Radiology, Adana, Turkey. koczafer@gmail.com
authors.forename: Zafer
authors.initials: Z
authors.lastname: Koc
authors.forename: Serife
authors.initials: S
authors.lastname: Ulusan
authors.forename: Levent
authors.initials: L
authors.lastname: Oguzkurt
authors.forename: Naime
authors.initials: N
authors.lastname: Tokmak
mesh_terms: D000005:Abdomen / Q000098:blood supply; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006503:Hepatic Veins / Q000002:abnormalities / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000002:abnormalities / Q000000981:diagnostic imaging*; D012082:Renal Veins / Q000002:abnormalities / Q000000981:diagnostic imaging*; D017678:Sex Distribution; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014682:Vena Cava, Inferior / Q000002:abnormalities / Q000000981:diagnostic imaging*