Abdominal CT belongs to the category of imaging tests, which are tomographic and non-invasive. Electronic colonoscopy is an endoscopic examination, which is relatively painful and invasive. Abdominal CT is mainly to understand the structure of the abdominal cavity organs, that is to say, you can find out whether there are occupying lesions in the abdominal cavity, it is difficult to find the tiny lesions. Electronic colonoscopy is mainly to understand the intestinal tract, can understand the intestinal mucosa whether there are lesions and the specific lesions. For colonoscopy, it is also possible to forceps lesions under visualization and send them for pathological biopsy, or to perform colonoscopic therapeutic surgery. Abdominal CT is only an indirect examination, which can indirectly determine whether there are lesions in the intestine. It is difficult to determine whether there are lesions in the intestinal tract, such as small tumors, or intestinal erosions, polyps, and so on.