Transposition and variant termination of azygos and hemiazygos veins: an extremely rare variation
- PDF / 1,172,971 Bytes
- 4 Pages / 595.276 x 790.866 pts Page_size
- 6 Downloads / 152 Views
ANATOMIC VARIATIONS
Transposition and variant termination of azygos and hemiazygos veins: an extremely rare variation Satheesha B. Nayak1 · K. V. Soumya2 Received: 4 March 2020 / Accepted: 10 April 2020 © Springer-Verlag France SAS, part of Springer Nature 2020
Abstract Azygos system of veins is the main source of venous drainage from the thoracic wall. Knowledge of azygos vein anomalies could be of importance to cardiothoracic surgeons and radiologists. We report a rare variation of azygos vein as seen in an adult male cadaver aged 65 years approximately. The azygos vein was formed by the union of left ascending lumbar and subcostal veins. It coursed upwards on the left side of descending thoracic aorta and crossed the left subclavian artery and the left vagus to terminate into the left brachiocephalic vein. It received left superior intercostal vein and left fifth to eleventh posterior intercostal veins. The hemiazygos and accessory hemiazygos veins were situated on the right side of the vertebral column. They received the right posterior intercostal veins and terminated into the azygos vein at the level of eighth thoracic vertebra. Keywords Azygos vein · Hemiazygos vein · Accessory hemiazygos vein · Variation · thoracic veins
Introduction The azygos system of veins drains the venous blood from the thoracic wall into the superior vena cava. These veins are situated closed to the vertebral column, in the posterior mediastinum. They also form an anastomotic channel between superior and inferior vena cava and help in shunting the blood either way in case of blockage of one of these great vessels. Normally, the azygos vein is formed by the union of right ascending lumbar and subcostal veins. It runs upwards in the posterior mediastinum along the right side of descending thoracic aorta and thoracic duct and arches over the root of right lung before opening into the superior vena cava. It receives the right superior intercostal vein, fifth to eleventh right posterior intercostal veins, and some oesophageal and mediastinal veins. The accessory hemiazygos vein is formed by the union of the left fifth to eighth posterior intercostal * K. V. Soumya [email protected] 1
Melaka Manipal Medical College (Manipal Campus), Manipal Academy of Higher Education, Madhav Nagar, Manipal, Karnataka State, India
Department of Mathematics, Manipal Institute of Technology, Manipal Academy of Higher Education, Madhav Nagar, Manipal, Karnataka State 576104, India
2
veins. The hemiazygos vein is formed by the union of left ascending lumbar and subcostal veins. It receives left ninth to eleventh posterior intercostal veins. These two hemiazygos veins run along the left side of the descending thoracic aorta and cross in front of the body of eight thoracic vertebrae to open into the azygos vein. Azygos vein is known to show variations in its origin, course, termination and tributaries. It may be absent in some cases or may be doubled or may be formed as the continuation of inferior vena cava. We found an extremely rare variatio
Data Loading...
