Hemiazygos vein at a glance
- What it is
- The hemiazygos vein is the left-sided equivalent of the lower azygos vein.
- Location
- It begins from the left ascending lumbar and left subcostal veins, ascends on the left of the vertebral column and at about T8 to T9 crosses behind the aorta and esophagus to join the azygos vein. It receives the lower (about ninth to eleventh) left posterior intercostal veins.
- Function
- It drains the lower left posterior thoracic wall.
- Body system
- Cardiovascular · single, midline structure
- FMA ID
- FMA4944 (Foundational Model of Anatomy)
Key facts
- It forms part of the azygos system.
- Its arrangement varies widely; it may be joined to the accessory hemiazygos vein as one continuous vessel.
Structures next to the hemiazygos vein
The nearest named structures in the 3D model, measured from the centre of each part:
- Intervertebral disk of tenth thoracic vertebra · skeletal
- Tenth thoracic vertebra · skeletal
- Eleventh thoracic vertebra · skeletal
- Intervertebral disk of eleventh thoracic vertebra · skeletal
- Descending aorta · cardiovascular
- Intervertebral disk of ninth thoracic vertebra · skeletal
- Ninth thoracic vertebra · skeletal
- Longissimus thoracis · muscular
- Twelfth thoracic vertebra · skeletal
- Spinalis thoracis · muscular
References
- Foundational Model of Anatomy: Hemiazygos vein (FMA4944). EMBL-EBI Ontology Lookup Service.
- OpenStax. Anatomy and Physiology 2e, §20.1 Structure and Function of Blood Vessels. Rice University, 2022.
- Mitsuhashi N. et al. (2009). BodyParts3D: 3D structure database for anatomical concepts. Nucleic Acids Research 37, D782–D785. Data © The Database Center for Life Science, CC BY 4.0.
Explore the whole body in the interactive 3D human anatomy model, or browse the A–Z list of human structures.