After gastric anastomosis, regular review is needed, and the review can usually choose CT scan or scan + enhancement of the abdomen, gastroscopy and so on. Abdominal CT scanning or scanning + enhancement can clarify whether there are occupying lesions in the stomach, and understand the size, shape and location of the lesions, etc. It can also look at the condition of the gastric anastomosis and the surrounding area, but it is not as intuitive as gastroscopy. Gastroscopy, through the endoscope, can visualize the situation of the residual stomach and the anastomosis, and if there is a suspicious situation, it can also take biopsy to do pathology to further clarify the situation. Gastroscopy is a kind of invasive operation, before performing this operation, it is necessary to exclude the contraindications (such as psychiatric patients who can not cooperate, suspected of gastrointestinal perforation, etc.), and obtain the signature of the patient or his family members to agree to carry out.