Thyroid ultrasound is a routine medical checkup and the detection rate of thyroid nodules is increasing, so what should we do when we encounter a thyroid nodule? The criteria for grading thyroid nodules on ultrasound are as follows: divided into 0-6 grades, a total of 7 grades. Grade 0: more specific, the clinical meaning is that the results of this examination are meaningless and need to be examined again or other examinations; 2. Grade 1: means that the patient’s thyroid gland is normal, no obvious nodules, cysts, calcifications, etc., which is a good examination result; 3. Grade 2: thyroid nodules are benign, no risk, solid isoechoic or hyperechoic nodules; 4. Grade 3: thyroid The higher the grade, the greater the possibility of malignancy. Usually, the risk of malignancy is 5%-10% for 4a, 10%-70% for 4b, and more than 75% for 4c. The longitudinal and transverse ratios are observed and basically the nodule is considered malignant. The likelihood of a grade 5 nodule being benign is very small; 7. Grade 6: pathologically confirmed malignant nodules. First of all, it depends on which grade to decide the principle of further treatment. If it is grade 1-3, you can rest assured, if grade 4, it is recommended to improve the thyroid puncture cytology, and grade 5-6 need to see a specialist to improve the evaluation and further treatment. In addition, the following tests should be completed: 1. Serological examination Abnormal thyroid function cannot exclude thyroid cancer but indicates that it is less likely. Patients with medullary thyroid carcinoma have elevated serum calcitonin levels, but require stimulation with pentagastrin and calcium in the early stages of C-cell proliferation. 2.Nuclear scan The scan is less significant in distinguishing benign and malignant lesions. Most benign and malignant substantial nodules are hypofunctional relative to the surrounding normal glandular tissue; therefore, detection of cold nodules is rarely specific, and overlapping uptake of nuclide from surrounding normal glandular tissue can miss small nodules. Many thyroid cancers can take up Tc, so there are still some cancer cases in hot nodules. PET/CT Positron emission tomography (PET) can be used to examine nodular thyroid lesions and identify benign and malignant tumors, and proton magnetic resonance seems to identify normal glandular tissue and cancerous tissue. 4.Thyroid fine needle aspiration cytology (FNAC) FNAC results have a 90% compliance rate with surgical pathology results. There is only a 5% false-negative rate and a 5% false-positive rate. The compliance rate of course depends on the success rate of the operator and varies widely.