Anatomic variations: a rare variant of formation of the portal vein.

The portal vein derives from the vitelline veins, a component of the extraembryonic venous system, and is normally formed by the confluence of the superior mesenteric and splenic vein. The knowledge of the anatomy of the portal vein and its abnormalities is important for interventional and surgical procedures. Variant portal architecture is a common finding during imaging studies. Ultrasonography, computed tomography and magnetic resonance are non-invasive methods for studying and understanding portal vein's anatomy and abnormalities. We describe a rare case of variation in the formation and course of the portal vein. To the best of our knowledge, there is no evidence of this kind of abnormality in literature.