It is important to relax as much as possible during this phase until the CT scan is complete. After the exam is complete, the rectal contrast will be drained and the patient may go to the bathroom. It is important to eliminate as much food remains as possible from the stomach, intestines and rectum in order to help the sensitivity of the CT exam using rectal contrast. Food and food remains can mimic disease when the oral contrast is present. The preparation time varies depending on the actual exam as well as the imaging center's requirements.
Patient preparation varies from center to center, depending on a number of issues.
Always check with the imaging center where the actual exam will take place to confirm the actual preparation recommendation. In general, barium and gastrografin contrast are safe and pass through the gastrointestinal tract in the same fashion as food or drink. Minor side effects such as constipation may happen. Certain medical conditions such as a perforated ulcer, or certain colon conditions may indicate the use of gastrografin instead or barium. The referring physicians and or radiologist will decide which type of contrast material is most appropriate based on a patient's specific condition.