A thyroid nodule detected by ultrasound is defined as an isolated lesion in the thyroid gland that has a different sonographic presentation than the surrounding parenchyma. Features to look for on ultrasound scan of thyroid nodules include nodule size, nodule echogenicity (very hypoechoic, hypoechoic, isoechoic, strong echogenicity, mixed echogenicity), composition (cystic, solid or cystic solid) and shape (aspect ratio) compared to the thyroid parenchyma or adjacent muscles, as well as the presence of calcification (microcalcification, coarse calcification or peripheral calcification), the presence of peripheral halo signs, regularity of morphology, border The presence or absence of blood flow (peripheral or internal) should also be observed. In addition, the relationship between the nodule and the surrounding soft tissues should be noted to determine whether the nodule has broken through the envelope and invaded adjacent structures. Furthermore, the presence of enlarged lymph nodes in the neck should be determined. I. Typical benign nodules: nodules that are cystic or cystic in nature; cystic nodules containing punctate colloidal strong echogenicity; spongy or honeycomb nodules; multiple scattered fine hypoechoic nodules within a coarse grid-like separation within the parenchyma of Hashimoto’s thyroiditis; hyperechoic nodules within Hashimoto’s thyroiditis. Poorly defined borders may be a manifestation of nodular goiter. Typical malignant thyroid nodules: usually solid, with aspect ratio greater than 1; hypoechoic or very hypoechoic nodules with increased blood flow and microcalcifications; coarse calcifications and peripheral calcifications may also be seen in malignant nodules; if the nodules show irregular margins, burrs, lobulation or blurred borders, they are more likely to be malignant. When thyroid cancer metastases to lymph nodes, the lymph node ultrasound shows: the ratio of long to short axis is reduced (nearly round shape), the internal echogenicity is enhanced and thickened, the lymphatic portal structure disappears, and the more characteristic changes are: small calcified dots in the lymph nodes and partial or total cystic changes. It is important to note that it is often difficult to distinguish between lymph node enlargement in the central region due to Hashimoto’s thyroid inflammation and metastasis. Finally, other atypical thyroid cancers, such as: cystic thyroid cancer, thyroid cancer with wise-tail sign, thyroid cancer with acoustic halo or peripheral calcification, require vigilance.