How would you describe a single structure or organ that is not uniform in texture or composition in ultrasound?

A single structure or organ that is not uniform in texture or composition is described as heterogeneous in ultrasound. This term indicates that the structure displays a variety of echogenicities, suggesting that its internal composition is mixed, featuring different types of tissues or cellular structures. For instance, many organs, such as the liver or kidneys, may have regions that differ in density or composition due to factors like cysts, tumors, or fatty changes, and these variations can be visualized in ultrasound imaging.

In contrast, a homogeneous description implies that the structure has a uniform texture and composition throughout, indicating that all the tissue types have similar acoustic properties. Isotropic refers to materials that have the same properties in all directions, while anisotropic materials exhibit different properties when measured along different axes. Neither isotropic nor anisotropic directly relates to the textural and compositional variance that defines a heterogeneous structure. Thus, the correct choice captures the complexities seen in various anatomical features during ultrasound examinations.