Anomalous accessory hemi-azyos system with persistent cranial segment of posterior cardinal vein - A case report
J. Morphol. Sci., vol.26, n3-4, p.0, 2009
Anomalies of the azygos system of vein are not uncommon. The case presented here exhibits persistent cranial part of the left posterior cardinal vein. This embryological variation gives rise to a well developed venous channel to the left side of the aortic arch and the thoracic aorta and drains the upper six left intercostals spaces. The superior intercostal vein on the left drains into this venous channel. The channel itself drains into the left brachio-cephalic vein after crossing the arch of aorta vertically on its left. Any communication between this anomalous channel and the azygos system on the right couldn’t be found. The inferior hemi-azygos system on the left is rudimentary. This persistent cephalic part of the posterior cardinal vein serves as a communication between the superior hemi-azygos vein to the brachio-cephalic vein on the left side. The existence of such an anomaly, the position of this vein and its proximity to the structures near the arch of aorta should be taken into consideration to avert radiological mis-diagnosis and surgical complications.
azygos system, posterior cardinal vein, hemi-azygos vein, brachio-cephalic vein, oblique vein of left atrium.