Spatial average density corresponds to?

Spatial average density corresponds to?

• A. Size of crystal in machine
• B. Area of sound head
• C. Frequency
• D. Time of exposure

Answer: (A)

Spatial distribution of ultrasound energy, or how energy is spread across the treatment area, is governed by the emitting surface of the transducer. The crystal size defines the beam’s footprint on the tissue; a larger crystal emits energy over a broader area, shaping the spatial average density of the field. Frequency and exposure duration affect how the energy interacts with tissue and how much total energy is delivered, but they don’t set the area over which that energy is spread. So the main factor determining spatial average density is the size of the crystal in the machine.

Spatial distribution of ultrasound energy, or how energy is spread across the treatment area, is governed by the emitting surface of the transducer. The crystal size defines the beam’s footprint on the tissue; a larger crystal emits energy over a broader area, shaping the spatial average density of the field. Frequency and exposure duration affect how the energy interacts with tissue and how much total energy is delivered, but they don’t set the area over which that energy is spread. So the main factor determining spatial average density is the size of the crystal in the machine.