Purpose:To explore the 640 slice CT double phase enhanced scan and the use of carbonated drinks as contrast agents in TNM staging of gastric cancer,and to explore the diagnostic value of 640 slice CT and gastroscopy in advanced gastric cancer.Material and methods:A total of 56 patients with gastric carcinoma,among them 36 were male and 20 were female,they were all between the age of 37-81,with an average age of 59 years were collected from March 2017-March 2018.All patients have preoperative gastroscopy,preoperative gastroscope biopsy pathologic examination,abdominal CT scan and enhanced and postoperative pathologic examination;all groups are surgery.Postoperative pathological examinations were gastric cancer.The patients should not eat any food 12 hours before the examination and should not drink water for 6 hours.10 min before scanning intramuscular654-2,20 mg is given.Its purpose is to reduce gastric bowel peristalsis cramps and relieve the patient’s discomfort.Patients are then checked within 30 minutes of drinking the carbonated drink,which was 500 ml to achieve the goal of gastric cavity expansion.We are using the Toshiba 640 slice helical CT scans.Scan parameters: the tube voltage 120 kv,the current 300-350 ma,the scanning range is from right diaphragmatic top to duodenal horizontal section,and appropriate sweep down level according to different situations.Scan dynamic double period after enhancement scanning.Enhanced scan are done using MEDAD VISTRON CT high pressure syringe iodine was the former intravenous nonionic media sea alcohol(300 mg/m L)of about300 m L,flow rate of 3.0 m L/s.Using tracer scanning method,arterial phase delay of about 20-30 s,and venous phase delay of about 40-60 s.Conventional supine,according to different lesion location to sweep the prone position and lateral position.All scanned data are sent to a GE 3 d image workstation,using AW4.6 software and according to the need for multiplanar reconstruction(MPR)in the workstation.640 slice CT examination results were analyzed and were compared with clinical pathologic results after surgery;in advanced gastric cancer Borrmann general classification,640 slice CT and gastroscope compared with postoperative pathologic results.Results:The Findings in 56 patients with gastric cancer according to pathological T staging were as follows: T1 phase has 6 cases,T2 stage has 18 cases.T3 phase has 21 cases,T4 has 11 cases;the T stage of 640 slice helical CT were: T1 phase in 7 cases,T2 stage in 18 cases,20 were T3,T4 phase in 11 cases;The accuracy of CT on T1-T4 staging gastric cancer diagnosis accuracy were 56.0%,66.7%,76.1%,and 81.8%,it had a total accuracy of 70.5%.Kappa coefficient is 0.595.The 56 cases have had gastric cancer radical surgery,and at the same time,the lymph node groups to stomach,and at the stomach surgery to clean off 356 lymph nodes;CT detected 243 lymph nodes;after pathology confirmed,there are 127 with lymph node metastasis.When D < 1cm the metastasis rate is45.6%,when 1 cm < D < 1.5cm,the metastasis rate is 66.4%.The metastasis rate is 88.7% when D>1.5cm.Chi-square value is 18.127%,P= 0.000 < 0.001.Which suggest that metastasis rate exist which is significant different during the three groups.These groups of M0 and M1 accuracy were 87.4% and 100%.The total accuracy is 93.4%,after the finding of M stage results and pathology results consistency inspection;we found that after kappa coefficient is 0.854.It means that 640 M under the slice helical CT and pathological staging have a high consistency rate.According to the description of the proposed parting ways in the form of stomach cancer in general by German pathologist Borrmann,advanced gastric cancer can be divided into four types.In this study 4 cases were removed among the 56 cases because they were early gastric carcinoma,the remaining 52 cases are all advanced gastric cancer.640 slice helical CT was used to scan the other 52 cases to scan,and the diagnosis were Borrmann type I or nodular type in 5 cases;Borrmann type II is limited ulcer type which was present in 10 of the cases: Borrmann type III is infiltrating ulcer and had 14cases;Borrmann IV type had 23 of the cases.Gastroscopy was also done in all 52 of the patients at the same time,and the diagnosis results of gastroscopy was Borrmann type I or nodular type in 4 cases;Borrmann type II limited ulcer type in 5 cases:Borrmann type III,infiltrating ulcer type in 8 cases;and Borrmann IV in35 cases.Comparing these two kinds of diagnostic method to differentiate different staging and diagnosis of gastric cancer patients,the clinical outcome such as table 3.4.With 640 slice CT Borrmann type with 43 correct,the accuracy is 82.7%,while using gastroscope to Borrmann parting with 33 points correctly,the accuracy is 63.5%.Chi-square=6.136,P=0.041 <0.05.Gastroscope and CT accuracy exists significantly different in both the groups.Conclusion:640 slice CT to preoperative clinical TNM staging of gastric carcinoma,and the result has high consistency on the pathology after the operation,and the evaluation of preoperative clinical surgical procedure has important reference value.In the middle-late gastric cancer Borrmann parting,640 slice CT is superior to endoscopy,especially for the identification of Borrmann type II and Borrmann type III,and diagnostic sensitivity and accuracy of Borrmann IV gastric cancer were obviously higher than those of gastroscope.