A Case of the Malformation of Azygos and Hemiazygos System

A malformation of azygos and hemiazygos system were observed from the cadaver for anatomy practice in College of Medicine, Chungnam National University. The observing results were as followings ; Hemiazygos vein was connected with left superior vena cava and drained into coronary sinus, which engorged enough to fill up with blood about 20cc to 30cc. Communicating pathway from hemiazygos vein to azygos veln wasn't found the diameter of left brachiocephalic vein was very small, about 2mm to 3mm. And, the diameter of left internal jugular vein was smaller than that of right infernal jugular vein. In this case, the azygos and hemiazygos system ceased its development at early embryologic stage(around 7 week embryo) and didn't progress into next stage.