Identification of Structures

The difference between veins and arteries can be determined by compressibility, i.e. veins compress and arteries do not. Image 1 displays the normal internal jugular vein (IJV) and the carotid artery.

When the probe is pressed into the neck to compress the structures, the vein is obliterated while the artery remains, as shown in Image 2.

Meanwhile, if the patient carries out a Valsalva manoeuvre, the IJV dilates, as shown in Image 3. Furthermore, the shape of the vessels is different. Arteries tend to be circular in transverse view, with muscular walls, whereas veins are often oval.

Veins are readily compressible, arteries are not.
Image 1 Image 2 Image 3
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