Echodensity

Echodensity refers to the intensity of an ultrasound echo reflected from a tissue or structure. In medical ultrasound imaging, sound waves are emitted into the body and then reflected back as echoes. The strength of these returning echoes determines the echogenicity of the tissue.

Tissues that reflect many sound waves produce strong echoes and are described as hyperechoic or echogenic. These often appear brighter on an ultrasound image. In contrast, tissues that absorb or transmit most of the sound waves produce weak echoes and are described as hypoechoic or anechoic. Anechoic structures, which reflect virtually no sound, appear black on the image and typically contain fluid, such as a simple cyst.

The term echodensity is a qualitative descriptor, meaning it's used to compare the brightness of one structure relative to another within the same ultrasound image. For example, a lesion might be described as having increased echodensity compared to the surrounding tissue, suggesting it's hyperechoic. Conversely, a hypoechoic lesion would appear darker than the adjacent tissue. This descriptive approach is crucial for interpreting ultrasound findings and diagnosing various medical conditions. Understanding echodensity allows physicians to differentiate between normal and abnormal tissues.