Sonography Canada Physics Core Practice Exam

The attenuation coefficient in soft tissue is influenced by the frequency of the ultrasound wave, as higher frequencies typically lead to greater attenuation. The coefficient for soft tissue is approximately proportional to the frequency and is often modeled as 0.5 dB/cm/MHz. This means that for every megahertz (MHz) increase in frequency, there is an additional attenuation of 0.5 dB per centimeter of soft tissue.

By using this coefficient, practitioners can predict how deep ultrasound waves can penetrate into soft tissues before becoming significantly attenuated. This understanding is crucial for optimizing imaging settings and interpreting diagnostic imaging results effectively. The factor of 0.5x frequency accurately reflects the established relationship between frequency and attenuation in soft tissue, providing a reliable basis for calculations in clinical sonography.