A case of double inferior vena cava with renal, ovarian and iliac vein variation

We encountered a rare case of an anatomic variant of inferior vena cava (IVC) duplication with renal, ovarian and iliac vein variation in an 81-year-old Japanese female cadaver during a student dissection course of anatomy at Aichi Gakuin University School of Dentistry. The two IVCs ran upwards bilaterally to the abdominal aorta. The left IVC joined with the left renal vein (RV) to form a common trunk that crossed anterior to the aorta and ended at the right IVC. We detected a vein [interiliac vein (IiV)] connecting the two IVCs at the level of the aortic bifurcation. The IiV was formed by the union of two tributaries from the left IVC and a tributary from the left internal iliac vein (IIV) and ran obliquely upwards from left to right. Two right ovarian veins, arising separately from the ipsilateral pampiniform plexus, ran vertically in parallel to each other, and each one independently terminated at the right IVC and the right RV. Two right IIVs, connecting each other with small branches, ascended and separately joined the right external iliac vein. The right and left IIVs were connected to each other. These variations cause abnormal drainage, which could lead to clinical symptoms associated with the dysfunction of the vascular and urogenital systems. Here we describe the detailed anatomical features of the area and discuss the related anatomical and developmental aspects.