Ultrasound typically attenuates an average of how many dB/cm of travel for each megahertz of frequency?

Ultrasound waves attenuate as they travel through tissue, and this attenuation is influenced by the frequency of the ultrasound. For each megahertz of frequency, the average attenuation is commonly accepted to be around 0.7 dB/cm. This means that for every centimeter of tissue the ultrasound wave travels, it will lose roughly 0.7 dB of its intensity if the frequency is at 1 MHz. As frequency increases, the attenuation also increases, which is crucial to understand when selecting frequencies for imaging specific tissues or structures. This relationship between frequency and attenuation underlines the importance of frequency selection in clinical practice, as higher frequencies provide better resolution but result in greater attenuation, potentially limiting depth of penetration.