Go on an empty stomach There are medical imaging examinations that cannot be done without eating or drinking before doing so, such as barium meal examinations of the upper gastrointestinal tract, as well as PET/CT and DSA examinations. In addition, patients suspected of having intestinal obstruction, intestinal perforation, acute pancreatitis and those who do CT angiography or suspect the presence of stones should also do not eat or drink before doing the examination. Other patients should not only not eat before the examination, but also drink laxatives or take an enema from the anus to empty the fecal residue from the intestine, which is called intestinal preparation to avoid affecting the diagnosis of urinary stones or affecting the effect of barium enema. Bowel preparation is also necessary when gas in the intestinal cavity affects the diagnosis or when a fecal stone is suspected during an abdominal X-ray plain film. Removal of foreign bodies When you plan to enter the medical imaging department for medical imaging, the first thing you have to do is to remove all foreign bodies from the filming site to prevent foreign body artifacts from hindering the diagnosis of the image. For example, before you do a chest x-ray, you have to remove necklaces, jade pendants, as well as buttons, zippers, bras, and even clothing with painted words and paintings. Similarly, necklaces, buttons, and belts have to be removed when taking a pelvic exam. In the case of MRI, these metal foreign objects can not only seriously affect the image quality, but also produce a certain amount of heat and burn your skin during the examination. Therefore, it is best to wear cotton clothing when doing medical imaging examinations. White clothing is preferable, never black or dark gray, so that the doctor can centerline the photography for you. Cooperate with the doctor During the chest radiograph, the doctor will give you an order to inhale and hold your breath, and you have to do it. The purpose of inhaling is to allow the lungs to be filled with gas to create good contrast, and holding your breath is to avoid movement blur artifacts from breathing movement. The purpose of holding your breath during CT and MRI examinations of the chest and abdomen is not only to reduce motion blur artifacts, but also to avoid changes in the scan level caused by your irregular breathing, which may lead to missing lesions. Therefore, when doing the examination, follow the doctor’s instructions to do the relevant actions. Eat and drink enough There are also some medical imaging examinations that require eating and drinking enough to perform. For example, for CT examinations of the abdomen, it is important to know how much water to drink and when to drink it. For a CT examination of the upper abdomen, it is necessary to drink 300 ml of diluted contrast medium, and the examination can be performed a few moments after drinking. For a CT examination of the kidneys, the total amount of water to be drunk is 800 ml, and you have to wait 20 minutes before the examination can be performed. For prostate, bladder and gynecological ultrasound, you should also drink more water and make your bladder full before performing the examination. Because some tests require eating and drinking and others require fasting, there is an order of priority when doing these medical imaging tests at the same time. Usually, examinations that do not eat, drink, or give injections are given priority, while those that require eating, drinking, or even injections must be performed later. Otherwise, once the order of the tests is reversed and the tests that should have been done later are done first, the tests that should have been done earlier will have to wait for a week before they can be done. Aftercare work The medical imaging is not finished, you still have a lot of aftercare work to do. For example, after you have been injected with contrast for X-ray imaging or CT-enhanced scanning and imaging, you must take a 15-minute break in the rest room after the examination before leaving the medical imaging department to prevent allergic reactions. When you return home, you need to change your clothes and take a shower to remove radioactive contamination. Another point is to drink more tea and water, sufficient into metabolism and excretion. Keep in mind the contraindications Indiscriminate medical imaging can also cause adverse consequences and even death. Therefore, you should keep in mind the contraindications related to medical imaging examinations. More importantly, be truthful with your doctor about your condition, such as whether you have a history of allergies, including a history of penicillin allergy or a history of allergies when eating foods with high iodine content, such as seaweed. This will indicate whether your doctor can perform an imaging test on you. If you have a pacemaker or have shrapnel, metal implants, insulin pumps, etc. in your body, these are absolute contraindications to MRI.