A normal lymph node is expected to demonstrate which characteristic?

A normal lymph node is characterized by a hyperechoic fatty center. This hyperechoic area, typically referred to as the fatty hilum, is a distinguishing feature that helps in differentiating normal lymph nodes from abnormal ones. The presence of a fatty hilum indicates a benign structure, often associated with healthy lymphatic tissue, and reflects the presence of adipose tissue within the lymph node.

In contrast, other characteristics do not align with what is expected of a normal lymph node. For example, a round contour may be seen in various pathological processes, and hypervascularity is usually indicative of inflammation or malignancy rather than normality. Irregular wall margins can also suggest disease or neoplastic changes within the lymph node, which deviate from the expected smooth, well-defined borders found in a healthy lymph node. Therefore, the presence of a hyperechoic fatty center is crucial when assessing lymph nodes in sonography, as it confirms their normalcy.