Why is lowering frequency better for deeper structures?

• A. Higher frequencies increase attenuation exponentially
• B. Lower frequency reduces frame rate
• C. Lower frequency improves resolution
• D. Frequency has no effect on penetration

Answer: (A)

Penetration is governed by attenuation, which grows with frequency. As ultrasound waves travel through tissue, they lose energy, and this loss increases more for higher frequencies—often described as exponential growth. Lowering the frequency reduces this attenuation, allowing the beam to reach deeper structures and still return a detectable signal. This is why deeper targets are imaged with lower-frequency settings or transducers. Keep in mind that while lower frequency improves depth penetration, it comes at the cost of resolution, since higher frequencies provide better detail. The other statements don’t fit: frame rate isn’t directly determined by frequency in this context, lower frequency does not improve resolution, and frequency does affect penetration.