Trunk vessels (aorta, vena cava, abdominal branches)
Hemiazygos vein
Vena hemiazygos
- Origin
- Formed on the left by the junction of the left subcostal and left ascending lumbar veins
- Insertion
- Ascends to T8-T9 level, crosses the vertebral column posterior to the aorta, esophagus, and thoracic duct to join the azygos vein
- Function
- Drains the 9th to 11th left posterior intercostal veins, lower esophagus, and mediastinum
- Innervation
- Thoracic sympathetic plexus
- Movement & chain
- Venous drainage across midline
- Palpation
- Not palpated directly
- Clinical
- Key systemic-portal and cavo-caval collateral conduit.
- Segmental innervation
- T8-T12 spinal levels
- In clinical practice
- CT interpretation of dilated retroperitoneal/mediastinal collateral veins
- Region in the model
- Trunk vessels (aorta, vena cava, abdominal branches)