All of the following are characteristics of veins on ultrasound except:

In the context of ultrasound characteristics of veins, the correct statement regarding what is not a characteristic of veins is that they exhibit increased vascular resistance. Veins are typically low-resistance vessels, which allows for the easy flow of blood back to the heart.

When veins are examined using ultrasound, they should demonstrate several specific characteristics:

• Compression refers to the ability of veins to collapse when pressure is applied, which is a normal response and helps distinguish veins from arteries during an ultrasound examination.

• Augmentation is the increase in venous flow that occurs when there is an increase in intra-abdominal pressure, such as during leg movement or calf muscle contraction.

• Phasicity describes the rhythmic variation in blood flow velocities due to the respiratory cycle, where flow increases during inspiration and decreases during expiration.

Understanding that veins have low resistance is crucial. This characteristic is fundamentally different from arteries, which typically exhibit higher vascular resistance due to their thicker walls and pressure dynamics. Thus, increased vascular resistance does not apply to veins and aligns with the characteristics being examined in the question.