ECT, i.e. emission computed tomography scanner, which can take advantage of the difference in metabolic concentration of radionuclides in diseased tissues in the body, processed on the computer and then imaged, has a wide range of applications in the clinic. In the clinic, ECT technology can help diagnose liver diseases, such as primary liver cancer, metastatic liver cancer, hepatic hemangioma, hepatic cysts, liver cirrhosis, fatty liver, chronic liver disease and so on. Its advantages are: common MRI, CT, ultrasound and other examinations, some of them are expensive, some of them have unclear visualization, which can easily cause misdiagnosis and delayed condition, and so on. ECT can improve the specificity of diagnosing diseases and make the lesion area easy to be distinguished from other lesions. For example, in the diagnosis of hepatic hemangioma, 99mTc-erythrocytes can gather in the hepatic blood pool in ECT, and the radioactivity of each part of the blood pool image reflects the amount of local blood volume, and those who have a clear manifestation of spherical overfilling can be diagnosed as hepatic hemangioma, and the specificity is almost 100%. The specificity is almost 100%. The specificity is almost 100%. Which examination method should be chosen in the clinic needs to be selected by the clinician in combination with the specific situation of the patient.