title: Anatomy of the inferior mesenteric artery evaluated using 3-dimensional CT angiography.
abstract: BACKGROUND
  The branching of the inferior mesenteric artery and vein varies among individuals. Three-dimensional CT angiography is a less invasive modality than traditional angiographic examination to assess the artery and vein.
  
  
  OBJECTIVE
  We aimed to demonstrate the clinical applicability of CT angiography by evaluating bifurcations of the inferior mesenteric artery and the positional relationship between the inferior mesenteric artery and vein.
  
  
  METHODS
  This was a prospective observational study of patients undergoing preoperative CT angiography.
  
  
  METHODS
  This study was conducted at a single tertiary care institution in Japan.
  
  
  METHODS
  A total of 471 consecutive patients who underwent preoperative CT angiography from April 2012 to December 2013 were prospectively enrolled.
  
  
  METHODS
  The branching pattern of the inferior mesenteric artery, the positional relationship between the inferior mesenteric artery and vein, and the associations between inferior mesenteric artery length and clinical features were evaluated.
  
  
  RESULTS
  The length of the inferior mesenteric artery varied widely, from 10.1 to 82.2 mm. In 41.2% patients, the left colic artery arose independently from the sigmoid artery, and in 44.7% of the patients, the left colic artery and sigmoid artery had a common trunk, whereas the left colic artery did not exist in 5.1%. The left colic artery was located lateral to the inferior mesenteric vein at the level of the origin of the inferior mesenteric artery in 73.0% of the patients. The incidence of a short inferior mesenteric artery was significantly increased in men with high BMIs (75.0%).
  
  
  CONCLUSIONS
  Three-dimensional reconstruction was performed by the use of a single software, and angiographic examination was not performed. Therefore, accuracy and reliability of the 3-dimensional reconstruction could not be established for each modality.
  
  
  CONCLUSIONS
  Using 3-dimensional CT angiography, preoperative understanding of the anatomic vascular variations can be easily obtained, which would help surgeons to safely perform laparoscopic surgery in the left-side colon and rectum.
authors.affiliation: Department of Surgical Oncology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Murono
authors.forename: Kazushige
authors.initials: K
authors.lastname: Kawai
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Kazama
authors.forename: Soichiro
authors.initials: S
authors.lastname: Ishihara
authors.forename: Hironori
authors.initials: H
authors.lastname: Yamaguchi
authors.forename: Eiji
authors.initials: E
authors.lastname: Sunami
authors.forename: Joji
authors.initials: J
authors.lastname: Kitayama
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D063405:Anatomic Variation; D000792:Angiography; D015992:Body Mass Index; D012809:Colon, Sigmoid / Q000098:blood supply*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D017537:Mesenteric Artery, Inferior / Q000000981:diagnostic imaging*; D008642:Mesenteric Veins / Q000000981:diagnostic imaging*; D008875:Middle Aged; D050177:Overweight; D011446:Prospective Studies; D012007:Rectum / Q000098:blood supply*; D012737:Sex Factors; D014057:Tomography, X-Ray Computed; D055815:Young Adult