Which intensities are the same for both Continuous Wave (CW) and Pulsed Wave (PW) sonography?

In sonography, understanding the characteristics of intensity is crucial for analyzing the behavior of ultrasound waves, particularly when differentiating between Continuous Wave (CW) and Pulsed Wave (PW) modalities. The intensities being evaluated have specific definitions that inform their relationship in both modes of sonography.

When considering the correct response, pulsed average intensity refers to the average intensity of the ultrasound wave during the “on” time of the pulse, while temporal average intensity refers to the overall average intensity across both the “on” and “off” times, accounting for the duty factor. Both CW and PW sonography report these as averages, though their specific calculations can differ based on the method of wave propagation.

The key distinction for the correct answer lies in the fact that in CW systems, the wave is continuously transmitted, thus the pulsed average intensity can be equivalent to the temporal average intensity due to the continuous nature of the signal. In contrast, PW involves pulsed transmission and typically has a duty cycle, which can result in different average intensities; however, it is essential to recognize that in the context of the question, both modalities report these averages consistently in cases that can be directly compared.

By contrast, the other combinations of intensities refer to interactions of