How to detect thyroid lesions and determine whether the nodules are benign or malignant; in addition to being detected by oneself or others because the thyroid gland is enlarged and causes the neck to become thicker, only 3%-7% of nodules are detected through a doctor’s examination (palpation), and ultrasound detects lesions in 20%-79% of the cases, so most of the patients discover the thyroid nodules when they have an ultrasound examination of the thyroid gland during a physical examination. Some of them are found during X-ray, CT and MRI examinations of the neck or chest for other diseases. When a thyroid nodule is found, the main concern of the patient or family is whether the nodule is benign or malignant? How to confirm the diagnosis! Therefore, ultrasound is the most commonly used test. Ultrasound of the neck should be performed if the doctor suspects by palpation, or if there are “thyroid nodules” indicated by X-ray, CT, MRI, or PET. ultrasound can not only detect very small thyroid nodules, but also determine whether the nodules are multiple or single, whether they are substantial or cystic, and whether the size of the thyroid, the size of the nodules, and the size of the nodules can be observed. size of the thyroid gland, the size of the nodule, whether the shape is regular, whether the border is clear, whether there are calcified foci, as well as the blood flow within and around the nodule, and also check the situation of the lymph nodes in the neck. The benign or malignant nature of thyroid nodules can be initially determined by ultrasound, but of course, the accuracy of ultrasound is closely related to the experience of the sonographer. At the same time, ultrasound can be used as a dynamic means of examination, regular review, to observe whether the nodules are rapidly enlarged, whether the morphology has changed, in order to provide the basis for clinical diagnosis of malignant nodules. In general, patients who are suspected of having malignant thyroid nodules and do not undergo surgery for the time being can have their ultrasound examination reviewed every 3 months-6 months, and for benign thyroid nodules, ultrasound review can be performed every 6 months, or once a year. All patients with thyroid nodules should be tested for thyroid function, primarily serum TSH levels. Calcitonin is tested if necessary to rule out medullary carcinoma. Preoperative final diagnosis of benign and malignant thyroid nodules must be performed by thyroid puncture biopsy, which is usually taken under the guidance of ultrasound, and puncture pathology of nodules suspected of malignancy. Treatment of thyroid nodules For benign thyroid nodules, unless the lumps are large and have pressure symptoms, or the lumps are large and affect the aesthetics, surgery is generally not required. Surgery can be performed when ultrasound examination suggests the possibility of thyroid cancer, or when thyroid cancer is confirmed by thyroid puncture pathology. Pathologic examination of the nodule is performed during surgery to clarify the diagnosis, in order to determine the extent of thyroidectomy, and the extent of lymph node dissection. Since most thyroid cancers are differentiated thyroid cancers, surgical removal of the thyroid gland is the most effective treatment. After thyroid surgery, those with hypothyroidism need to be given thyroxine replacement therapy. Thyroxine suppressive therapy must be given after surgery for malignant nodules. Some patients also require iodine 131 therapy if necessary.