What do "flow phantoms" simulate in ultrasound testing?

Flow phantoms are specially designed materials that mimic the properties of blood, allowing them to simulate real blood flow. This simulation is crucial for validating various ultrasound equipment and techniques. By using flow phantoms, technicians can assess the accuracy and effectiveness of ultrasound systems in measuring blood flow characteristics such as velocity and direction.

The ability to create controlled conditions in a flow phantom enables a standard against which ultrasound measurements can be compared. This ensures that the ultrasound equipment is properly calibrated and can provide reliable data in clinical settings, contributing to accurate diagnoses and patient care. The physical characteristics of these phantoms, including viscosity and flow patterns, closely imitate those of actual blood, making them essential tools in the training and evaluation of vascular ultrasound technology.

In contrast, other options do not align with the primary function of flow phantoms. For example, while pressure changes in arteries and vascular resistance are important aspects of hemodynamics, these are not the primary focus of flow phantoms. Similarly, flow phantoms do not simulate electric currents in tissues, as their primary purpose is to replicate fluid dynamics rather than electrical properties.