Which transmit frequency should you select for maximum penetration?

Which transmit frequency should you select for maximum penetration?

• A. 3.0 MHz
• B. 3.5 MHz
• C. 4.0 MHz
• D. 5.0 MHz

Answer: (A)

Penetration depth in ultrasound is governed by attenuation, which rises with frequency. Lower frequency waves lose less energy as they travel through tissue, so they reach deeper structures. When you need to image deeper anatomy, you choose a lower-frequency transducer. Among the options, 3.0 MHz is the lowest, so it provides the greatest penetration. The trade-off is that image resolution decreases at lower frequencies, so the deeper you go, the blurrier the detail can be.

Penetration depth in ultrasound is governed by attenuation, which rises with frequency. Lower frequency waves lose less energy as they travel through tissue, so they reach deeper structures. When you need to image deeper anatomy, you choose a lower-frequency transducer. Among the options, 3.0 MHz is the lowest, so it provides the greatest penetration. The trade-off is that image resolution decreases at lower frequencies, so the deeper you go, the blurrier the detail can be.