title: Intrahepatic portal venous variations: prevalence with US.
abstract: A prospective ultrasound study was undertaken to determine the prevalence of variants of the intrahepatic branching of the portal venous system. Of the 507 patients examined, 55 (10.8%) had trifurcation, 24 (4.7%) had a right posterior segmental branch arising from the main portal vein, 22 (4.3%) had a right anterior segmental branch originating from the left portal vein, and one (0.2%) had absence of the horizontal segment of the left portal vein. Not one patient had complete absence of the right portal vein in this series. The remaining 405 (79.9%) patients had normal distribution of the portal venous system; some patients of the normal group had minor variations in distribution.
authors.affiliation: Department of Diagnostic Radiology, Montreal General Hospital, Que, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Atri
authors.forename: P M
authors.initials: PM
authors.lastname: Bret
authors.forename: M A
authors.initials: MA
authors.lastname: Fraser-Hill
mesh_terms: D006801:Humans; D011168:Portal System / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D011169:Portal Vein / Q000002:abnormalities* / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D014463:Ultrasonography