What does hemiazygos vein mean?
What does hemiazygos vein 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.
What is the function of the hemiazygos and accessory hemiazygos veins?
The accessory hemiazygos vein drains the superior left hemithorax. It arises from the 4th to 8th left posterior intercostal veins and lies longitudinally on the left side of the vertebral bodies. It also drains the left bronchial vein and some veins from the oesophagus.
Which vein drains into hemiazygos?
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].
Where is the hemiazygos vein located?
posterior mediastinum
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.
How is hemiazygos vein formed?
Origin. The hemiazygos vein is formed by the confluence of the left ascending lumbar and left subcostal veins.
What is azygos and hemiazygos vein?
The azygos venous system is located on either side of the vertebral column and drains the viscera within the mediastinum, as well as the back and thoracoabdominal walls. This system consists of the azygos vein and its two main tributaries: the hemiazygos vein and the accessory hemiazygos vein.
What is azygos and hemiazygos?
How is accessory hemiazygos vein formed?
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.
How do you identify azygos vein?
The azygos vein originates at the junction of the right ascending lumbar and subcostal veins, entering the chest through the aortic hiatus. It ascends along the anterolateral surface of the thoracic vertebrae and arches ventrally to the right main bronchus at T5–T6, draining into the SVC.
Where is the azygos and hemiazygos veins located what muscles do they supply blood to?
The azygos and hemiazygos veins are located on either side of the vertebral column, and drain the back and the thoracic and abdominal walls. Their anatomy is variable. They assume particular importance in cases of SVC obstruction where they provide important collateral pathways.
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.