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The lower vena cava is normal
Last reviewed: 20.11.2021
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The lower hollow vein usually changes its diameter during the respiratory cycle, while it compresses during inspiration, expands during expiration: these changes in diameter make it possible to recognize and differentiate the lower vena cava from the aorta. In the transverse sections, the inferior vena cava is flat or oval, while the aorta is always rounded: The lower hollow vein is flatter during inspiration and more oval during vodoha, especially with forced inspiration (Valsalva's test).
After recognizing the inferior vena cava, a thorough examination of the hepatic and renal veins, and in some cases of iliac veins:
In elderly patients, the aorta can move the lower vena cava to the right or lie in front of it. Very rarely, there may be two lower hollow veins on either side of the aorta: they can be considered as hypoechoic, enlarged lymph nodes. The change in the diameter of these formations during the respiratory cycle will make it possible to differentiate the veins from other solid structures.