"The inferior vena cava receives the lumbar veins draining the lateral and posterior abdominal wall. The right lumbar veins are shorter and enter the posterior surface of the inferior vena cava directly. On the left-hand side, the veins pass behind the aorta and communicate via the ascending lumbar vein which runs parallel to the inferior vena cava. The first and second lumbar veins on the left side usually don't reach the inferior vena cava directly and instead join the ascending lumbar vein. The third and fourth lumbar veins enter the inferior vena cava posteriorly. The right and left ascending lumbar veins each ascend on the vertebral bodies at the root of the transverse processes deep to the psoas muscle and join the subcostal veins to form the azygos vein on the right and the hemiazygos vein on the left before entering the thorax."
"It should be noted that the posterior abdominal wall does not have a consensus definition and the psoas and quadratus lumborum muscles are sometimes included as the posterior compartment of the retroperitoneum 4."
Expected headings
"Musculotendinous"
"CT and MRI"
"The ascending lumbar veins, azygos and hemiazygos veins can become more visible if enlarged in inferior vena cava or superior vena cava obstruction."