ECT is a tomography scan of radionuclide, which is suitable for early lesion screening or early lesion definitive diagnostic examination, such as bone metastatic tumor of bone, breast cancer, thyroid cancer, where early lesions can be detected, and the lesions can be detected 3-6 months earlier compared to conventional X-ray examination, so ECT is commonly used as early lesion diagnostic screening by physicians. For bone diseases, even if there is no bone pain, early examination facilitates lesion detection, which is of great benefit in all aspects such as preoperative and postoperative clear judgment and treatment plan development.