Ultrasound is the preferred method of examination for thyroid nodules. It can determine the size, number, location, texture (cystic or solid), shape, borders, envelope, and structural features of the thyroid gland. Certain ultrasound features can help in the differentiation of benign and malignant thyroid nodules. Benign features: 1. Purely cystic nodules. 2. Nodules consisting of multiple small vesicles occupying more than 50% of the nodule volume and showing spongy changes. 97% of the above are benign. Malignant features: 1, solid hypoechoic nodules. 2, rich blood supply in the nodule (under normal TSH). 3. Irregular nodule morphology and margins, halo absence. 4, Microcalcifications, pinpoint-like diffuse distribution of calcifications. 5, accompanied by abnormal ultrasound images of cervical lymph nodes, such as rounded lymph nodes, irregular or blurred borders, uneven internal echogenicity, calcification inside, poorly demarcated skin medulla, disappearance of lymph gates or cystic changes.