What is the attenuation coefficient in soft tissue expressed as a function of frequency?

The attenuation coefficient in soft tissue is indeed expressed as a linear function of frequency. In soft tissue, this relationship is often determined through empirical studies, showing that attenuation increases with frequency.

Specifically, the attenuation coefficient can generally be estimated using the formula ( \alpha = k \cdot f ), where ( \alpha ) is the attenuation coefficient, ( f ) is the frequency, and ( k ) is a constant that relates to the specific medium—in this case, soft tissue. This constant can vary based on the environment and specific properties of the soft tissue.

In soft tissue, the attenuation coefficient is typically around 0.5 dB/cm/MHz. Therefore, when examining this relationship, it is understood that as frequency increases, the attenuation coefficient also increases in a proportional manner. The frequency divided by two underlines this idea correctly, as higher frequencies lead to a higher rate of attenuation due to increased scattering and absorption of sound waves in the tissue.

The correct option reflects this well-established principle in ultrasonography, highlighting the importance of frequency on attenuation in soft tissue.