What is azygos and hemiazygos?

What is azygos and hemiazygos?

The azygos venous system arises from the supracardinal veins embryologically. The right supracardinal vein becomes the azygos vein, while the left supracardinal vein becomes the hemiazygos vein 4.

What drains into the accessory hemiazygos vein?

The accessory hemiazygos vein, also called the superior hemiazygos vein, drains the superior left hemithorax. In a majority of cases there is a small connection to the left superior intercostal vein, and rarely, 1–2% of the time, the accessory hemiazygos vein drains into the brachiocephalic vein [3].

What does the accessory hemiazygos drain into?

The accessory hemiazygos vein is formed by the confluence of the middle left posterior intercostal veins. It descends to the left of midline, adjacent to the thoracic vertebrae and crosses posteriorly to the aorta at the level of T7-8 to drain into the azygos vein.

What level does hemiazygos join azygos?

Accessory hemiazygos vein It joins the azygos vein behind the oesophagus at the level of T8.

What are the functions of the azygos the hemiazygos and the accessory Hemiazygos veins?

That is, the azygos vein serves to drain most of the posterior intercostal veins on the right side of the body, and the hemiazygos vein and the accessory hemiazygos vein drain most of the posterior intercostal veins on the left side of the body.

What is the difference between azygos and hemiazygos veins?

Thus, azygos means unpaired. The azygos vein is unpaired in that there is only one in the body, mostly on the right side. While there is the hemiazygos vein and its accessory on the left side of the body, they are considered tributaries of the azygos vein rather than its left-side equivalent.

Does hemiazygos vein drain into azygos?

The hemiazygos vein runs in the posterior mediastinum and drains into the azygos vein at the level of the eighth thoracic vertebra. Along its course, the hemiazygos vein receives several tributaries which include: ninth, tenth and eleventh left posterior intercostal veins, mediastinal and esophageal veins.

What does hemiazygos vein drain?

The hemiazygos vein helps to drain the left mediastinum and left lower esophagus. The hemiazygos vein crosses from left to right at approximately the level of T9 and terminates by emptying into the azygos vein.

What are the functions of the azygos the hemiazygos and the accessory hemiazygos veins?

What does the hemiazygos vein do?

What is the role of the azygos vein?

The azygos vein is a unilateral vessel that ascends in the thorax to the right of the vertebral column, carrying deoxygenated blood from the posterior chest and abdominal walls.

What does hemiazygos mean?

Medical Definition of hemiazygos vein : a vein that receives blood from the lower half of the left thoracic wall and the left abdominal wall, ascends along the left side of the spinal column, and empties into the azygos vein near the middle of the thorax.