Rich blood flow in thyroid nodules suggests that there are obvious blood supply vessels around the nodule and active metabolism. Common causes include high-functioning adenoma and thyroid cancer. 1. High-functioning adenoma: the cells secrete a large amount of thyroid hormones, with active metabolism and increased blood vessels, resulting in abundant blood flow. 2. Thyroid cancer: malignant proliferation of cells, active division, rich blood supply, nodules usually have irregular edges, microcalcification, aspect ratio disorder and other characteristics. Simply through the thyroid nodule blood flow is rich, can not determine the specific conditions, it is recommended to consult the doctor in time, further investigation, under the guidance of the doctor treatment.