3-MHz ultrasound heats tissue to a depth of

3-MHz ultrasound heats tissue to a depth of

• A. 1-2 cm.
• B. 2-3 cm.
• C. 4-5 cm.
• D. 6-7 cm.

Answer: (B)

Higher ultrasound frequency is absorbed more readily by tissues, so it heats more superficially. A 3 MHz transducer is considered high frequency, targeting shallow depths rather than deep layers. In clinical use, the heating effect from 3 MHz typically occurs around 2 to 3 centimeters beneath the skin, depending on tissue properties and coupling. That’s why the option describing a two-to-three centimeter depth best fits 3 MHz. Deeper heating (4–7 cm) would require lower frequencies, while 1–2 cm is at the very shallow end and can vary with setup.

Higher ultrasound frequency is absorbed more readily by tissues, so it heats more superficially. A 3 MHz transducer is considered high frequency, targeting shallow depths rather than deep layers. In clinical use, the heating effect from 3 MHz typically occurs around 2 to 3 centimeters beneath the skin, depending on tissue properties and coupling. That’s why the option describing a two-to-three centimeter depth best fits 3 MHz. Deeper heating (4–7 cm) would require lower frequencies, while 1–2 cm is at the very shallow end and can vary with setup.