Using ultrasound at 1.5 W/cm2 for 10 minutes can increase tissue temperature by approximately

• A. 2-3°F.
• B. 7-8°F.
• C. 10-12°F.
• D. 15-18°F.

Answer: (B)

Therapeutic ultrasound heats tissue by converting acoustic energy into heat, and how much it heats depends on how strong the beam is, how long you apply it, the frequency, whether the application is continuous or pulsed, and the tissue’s properties. At a continuous 1.5 W/cm2 for 10 minutes, the energy deposited in the treated tissue typically raises temperature by about 4°C, which is roughly 7–8°F. This level of heating is sufficient to produce modest increases in tissue perfusion and collagen extensibility, aiding in healing and flexibility. Individual factors like tissue depth, type, and coupling can shift the exact amount, but the 7–8°F range reflects common expectations for this setting.