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.
Purpose: 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.
Design: Prospective study.
Patient Sample: Ninety patients (48 males, 42 females) explored between July 2003 and February 2007.
Outcome Measures: 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.