Radiological evidence of anatomical variation of the inferior vena cava: report of two cases.

The inferior vena cava (IVC) is a retroperitoneal key structure whose location and integrity must be checked in every scan. A number of studies are reported in the literature concerning congenital variations of the inferior vena cava. Anatomical variations of this main venous trunk are relatively infrequent clinical findings during surgery or diagnostic procedures in patients without symptoms such as an aberrant venous drainage or abdominal pain. Among the other imaging techniques, computerized tomography is a non-invasive, effective technique for diagnosing diseases of the retroperitoneal space and, particularly, for detecting anomalies of the main vessels, such as the aorta or IVC, in asymptomatic patients. We present two cases of IVC variation as an incidental finding in patients studied by means of CT scan for the gradation of kidney carcinoma and pancreatic cancer respectively. Two different configurations of the system of the IVC (agenesis of the IVC with hypertrophy of the azygos vein and a double IVC respectively) were found in our cases. The embryological development of the IVC system is discussed, bearing in mind that knowledge of the different variations is important in order to avoid major surgical complications.