The most commonly used imaging test is gastrointestinal imaging, which is divided into upper gastrointestinal imaging and lower gastrointestinal imaging, as well as more commonly used cerebral angiography, tubal imaging, urinary system imaging, etc. The most commonly used imaging test is gastrointestinal imaging, which is divided into upper gastrointestinal imaging and lower gastrointestinal imaging. Let’s start with digestive tract imaging, digestive tract imaging is usually done on an empty stomach, oral barium sulfate solution is about 200-300ml, usually the solution is thicker, according to the doctor’s request, swallow it down one mouthful at a time, and every mouthful will be photographed, which is to check the upper gastrointestinal tract from the esophagus to the stomach, and it will be carried out step by step, and it usually lasts for about 10 minutes. After the sip, a full examination of the stomach will be done, and the patient will be asked to change various positions, on the examining bed, and just follow the doctor’s request. After this is done, the patient will be asked to do the middle GI after 2-3 hours, and then the lower GI after another 2-3 hours, which is the overall process. Most GI imaging especially full GI imaging takes 4-6 hours to do, this is if it goes well, if it doesn’t go so well, it can take more than 6 hours.