The presence of blood flow signals in a nodule indicates the presence of blood supply to the nodule, which can be seen in the state of more active cell development, and is commonly seen in thyroid nodules, breast nodules, liver nodules, and so on. 1. Thyroid nodule: If there is a nodule in the thyroid gland with blood flow signals, it may be seen in nodular goiter, acute thyroiditis, papillary thyroid tumor, follicular thyroid tumor and so on. 2. Breast nodule: If there is blood flow signal in the breast nodule, it may be breast hyperplasia, hemangioma or breast tumor. 3. Liver nodule: If there is a nodule with blood flow signal in the liver, if the blood flow signal is more, it may be liver tumor, and if the blood flow signal is less, it may be hemangioma. When there are nodules with blood flow signals, it should be combined with other auxiliary examinations such as blood routine, tumor markers, tissue puncture pathology and other examinations to comprehensively analyze the condition and carry out targeted treatment after clarifying the cause of the disease.