title: Accessory iliac vein: surgical implications.
abstract: BACKGROUND
  One of the main difficulties in using an anterior retroperitoneal approach in prosthetic lumbar disk replacement surgery is the exposure of the anterior aspect of the spine because of the risk of hemorrhage because of vascular injury when the venous structures are mobilized.
  
  
  OBJECTIVE
  The goal of our study was to use computed tomography (CT) to research for anatomic variations of the ileocaval drainage network, which were likely to complicate this type of procedure.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Ninety patients (48 males, 42 females) explored between July 2003 and February 2007.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  All the patients had a CT scan before disk replacement surgery to treat degenerative lumbar disk disease by a microinvasive, anterior retroperitoneal approach.
  
  
  RESULTS
  Eighteen of 90 patients presented with variations in their iliocaval drainage network: 3 cases of double inferior vena cava, 1 case of duplication of the inferior vena cava, 5 cases of ectopic internal iliac veins, 9 cases of accessory iliac veins.
  
  
  CONCLUSIONS
  Anatomical variations in the iliocaval venous drainage system are fairly frequent but easy to analyze by CT. Even if they have no functional impact, they must be analyzed and described because they can be of great interest in the preoperative workup for retroperitoneal lumbar surgery.
authors.affiliation: Department de Radiologie, Hopital Timone, Marseille Cedx, France. vincent.vidal@ap-hm.fr
authors.forename: Vincent
authors.initials: V
authors.lastname: Vidal
authors.forename: Olivier
authors.initials: O
authors.lastname: Monnet
authors.forename: Alexis
authors.initials: A
authors.lastname: Jacquier
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Bartoli
authors.forename: Patrick
authors.initials: P
authors.lastname: Tropiano
mesh_terms: D005260:Female; D006801:Humans; D007084:Iliac Vein / Q000000981:diagnostic imaging* / Q000601:surgery; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000601:surgery; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging / Q000601:surgery; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D011446:Prospective Studies; D011859:Radiography; D013123:Spinal Fusion; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging* / Q000601:surgery