CT findings of bilateral inferior vena cava:Differentiation from dilated retroperitoneal veins

ABSTRACT

We expierienced five cases of bilateral inferior vena cava for recent one year. We evaluated the CT findings of the cases and of dilated veins located in the left retroperitoneum (seven left gonadal, seven inferior mesenteric, and two left ascending lumber veins)in the viewpoints of the size, location and relation with the surrounding structures. Bilateral inferior vena cava (IVC) may be asymmetric and the left IYC may be smaller than other retroperitoneal veins with a round contour. The left lYC was located anterior to the spinal body and corresponded with contralateral vena cava in the anteroposterior plane. The gonadal vein was located anterior or anterolateral side of the psoas and always crossed the ureter. Most of the inferior mesenteric vein showed similar location to the opposite site of the vena cava in the anterolateral side of the psoas muscle, medial to the left ureter without crossing. The left ascending lumbar vein was similarly located to the left vena cava but dilated in a short segment. It is required to trace the vessel upward and downward and observe its continuity for correct differentiation. If it is impossible, some differential points suggested in the results of our study will be helpful for distinguishing them.