Which parameter relates to tissue heating?

Which parameter relates to tissue heating?

• A. Absorption
• B. Impedance
• C. Refraction
• D. Propagation speed

Answer: (A)

Tissue heating is driven by how much ultrasound energy the tissue absorbs. When energy is absorbed, it is converted into heat, so the absorption property of tissue directly determines how much heating occurs. Higher absorption (especially at higher frequencies) means more energy is converted to heat in the tissue. Impedance, refraction, and propagation speed describe other wave behaviors: impedance governs reflections at boundaries, refraction is the bending of the wave at interfaces with different speeds, and propagation speed tells how fast the wave travels through a medium. None of these directly quantify how much energy is deposited as heat in the tissue.

Tissue heating is driven by how much ultrasound energy the tissue absorbs. When energy is absorbed, it is converted into heat, so the absorption property of tissue directly determines how much heating occurs. Higher absorption (especially at higher frequencies) means more energy is converted to heat in the tissue.

Impedance, refraction, and propagation speed describe other wave behaviors: impedance governs reflections at boundaries, refraction is the bending of the wave at interfaces with different speeds, and propagation speed tells how fast the wave travels through a medium. None of these directly quantify how much energy is deposited as heat in the tissue.