Inferior vena cava in urology: importance of developmental abnormalities in clinical practice.

Anomalies of the inferior vena cava (IVC) have been known since 1793, when Abernethy first described a congenital, mesocaval shunt and azygous continuation of the IVC in a 10-month-old infant with polysplenia and dextrocardia. The IVC is formed by a complex process of embryogenesis during the sixth to tenth week of gestation. It forms from continuous appearance and regression of the three paired veins: posterior cardinal, subcardinal, and supracardinal. Improper completion of the developmental process may result in at least 14 anatomic anomalies, out of which the following four are usually encountered in clinical practice: duplication of the IVC, transposition or left-sided IVC, retroaortic left renal vein, and circumaortic left renal vein. It is suggested that the preoperative diagnosis of the vascular anomalies reduces the complication rate of abdominal vascular procedures. Our vast experience with approximately 400 kidney donors who were evaluated preoperatively with spiral CT scan with three-dimensional reconstruction (3D) reconfirmed this view. Thereafter, it became easier to choose the side and decide between laparoscopic vs. open approach. This prompted us to write the present article focusing on those developmental anomalies of the IVC that may be encountered by the urologist and their implication on the clinical practice.