Which frequency is used for deeper tissue heating?

Which frequency is used for deeper tissue heating?

• A. 1 MHz
• B. 3 MHz
• C. 5 MHz
• D. 10 MHz

Answer: (A)

Lower-frequency therapeutic ultrasound penetrates deeper into tissue because longer wavelengths are less attenuated, so more energy reaches deeper structures before converting to heat. Among the options, the lowest frequency travels deepest, making it the best choice for heating deeper tissues. In practice, 1 MHz is used when the target lies several centimeters beneath the skin. Higher frequencies like 3, 5, or 10 MHz heat more superficially, affecting tissues near the surface.

Lower-frequency therapeutic ultrasound penetrates deeper into tissue because longer wavelengths are less attenuated, so more energy reaches deeper structures before converting to heat. Among the options, the lowest frequency travels deepest, making it the best choice for heating deeper tissues. In practice, 1 MHz is used when the target lies several centimeters beneath the skin. Higher frequencies like 3, 5, or 10 MHz heat more superficially, affecting tissues near the surface.