title: Navigating the mesentery: part II. Vascular abnormalities and a review of the literature.
abstract: OBJECTIVE
  Vascular abnormalities present advantages and/or disadvantages for the patient undergoing surgery. The aims of this study were to define, classify and demonstrate the courses, and to assess the clinical value, of arterial and venous abnormalities in the central mesentery.
  
  
  METHODS
  We conducted a review of the anatomy of 340 patients planned for enrolment in the 'Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic MDCT Angiography' trial, 312 of whom were submitted to surgery. Vascular abnormalities were analysed in context with surgical notes and images. A meta-analysis of the literature was performed.
  
  
  RESULTS
  Arterial Abnormalities were found in 28 (8.2%) of the 340 patients and were classified into the following three groups based on anticipated surgical difficulty: group 1, accessory or replaced arteries to solid organs [14 (4.1%)]; group 2, arterial shunts [11 (3.2%)] between the coeliac trunk and the superior mesenteric artery, which resulted in bleeding in three patients; and group 3, common stem abnormalities [3 (0.9%)]. Two groups of superior mesenteric vein abnormalities were noted. The first included morphological abnormalities in a single vein [4 (1.2%)]: aneurysm [1 (0.3%)]; and ring variants of principal tributaries [3 (0.9%)]. The second included double superior mesenteric vein trunks [31 (9.1%)]: genuine bifid [10 (2.9%)]; and pseudo bifid [21 (6.2%)]. The meta-analysis revealed 26 articles, including 10 series of anatomical dissections or angiographies [1970 cases with 205 (10.4%) arterial abnormalities] and 16 case reports, none of which described a clinical or surgical setting.
  
  
  CONCLUSIONS
  Vascular abnormalities occur frequently. Arterial abnormalities are a hazard when inadvertent injury occurs during surgery. Preoperative knowledge of a bifid superior mesenteric vein is useful.
authors.affiliation: Department of Gastrointestinal Surgery, Vestfold Hospital, Tonsberg, Norway.
authors.forename: J M
authors.initials: JM
authors.lastname: Nesgaard
authors.affiliation: Faculty of Medicine, Department of Cellular Physiology and Metabolism, Anatomy Sector, University of Geneva, Geneva, Switzerland.
authors.forename: B V
authors.initials: BV
authors.lastname: Stimec
authors.affiliation: Department of Digestive Surgery, Akershus University Hospital, University of Oslo, Lorenskog, Norway.|Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: A O
authors.initials: AO
authors.lastname: Bakka
authors.affiliation: Institute of Clinical Medicine, University of Oslo, Oslo, Norway.|Interventional Centre, Gastrointestinal and Pediatric Surgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway.
authors.forename: B
authors.initials: B
authors.lastname: Edwin
authors.affiliation: Department of Digestive Surgery, Akershus University Hospital, University of Oslo, Lorenskog, Norway.|Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: D
authors.initials: D
authors.lastname: Ignjatovic
mesh_terms: D000368:Aged; D000792:Angiography; D003082:Colectomy / Q000009:adverse effects* / Q000379:methods; D015179:Colorectal Neoplasms / Q000150:complications / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008638:Mesenteric Arteries / Q000002:abnormalities* / Q000000981:diagnostic imaging; D008643:Mesentery / Q000098:blood supply*; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology*
keywords:  right colectomy; Colonic neoplasms/surgery; digestive arteries; imaging, three-dimensional; mesentery/blood supply; vascular anomalies