What term identifies the maximum intensity within the ultrasound beam?

What term identifies the maximum intensity within the ultrasound beam?

• A. Spatial average intensity
• B. Spatial peak intensity
• C. Temporal average intensity
• D. Pulse energy

Answer: (B)

In ultrasound, intensity changes across the beam’s cross-section and over time. The quantity that identifies the largest energy per unit area anywhere within the beam is the spatial peak intensity. It represents the maximum value of the beam’s spatial distribution, i.e., the brightest spot in the cross-section. This differs from the spatial average intensity, which is the mean intensity across the entire beam cross-section, and from the temporal average intensity, which averages intensity over time (taking into account the pulse’s on/off pattern). Pulse energy, on the other hand, measures the energy contained in each pulse, not the maximum instantaneous intensity within the beam.

In ultrasound, intensity changes across the beam’s cross-section and over time. The quantity that identifies the largest energy per unit area anywhere within the beam is the spatial peak intensity. It represents the maximum value of the beam’s spatial distribution, i.e., the brightest spot in the cross-section. This differs from the spatial average intensity, which is the mean intensity across the entire beam cross-section, and from the temporal average intensity, which averages intensity over time (taking into account the pulse’s on/off pattern). Pulse energy, on the other hand, measures the energy contained in each pulse, not the maximum instantaneous intensity within the beam.