What describes the number of decibels that occurs when sound travels 1 cm in tissue?

The attenuation coefficient is the term that describes the number of decibels that occur when sound travels a specific distance, such as 1 cm, in tissue. It quantifies the attenuation—loss of intensity—of an ultrasound wave as it travels through a medium. The attenuation coefficient is expressed in decibels per centimeter (dB/cm), providing a standardized way to understand how sound energy diminishes as it penetrates into the tissue.

Different tissues in the body will have varying attenuation coefficients due to their unique densities and compositions, affecting how much sound is lost during propagation. This coefficient is crucial for predicting image quality and depth of penetration in sonographic imaging.

On the other hand, terms like absorption rate, reflection coefficient, and attenuation rate convey different aspects of sound wave behavior. The absorption rate focuses on the energy absorbed by the medium, the reflection coefficient pertains to the amount of sound that is reflected back at an interface, and attenuation rate is more of a general term that may refer to the overall loss in energy as opposed to specifying how it changes over a defined distance. Thus, the attenuation coefficient is the most precise descriptor for the scenario presented.