Virtual colonoscopy (CT colonography)

• Fasting: A strict fast of solid foods for at least 6 to 8 hours before the test is required. On the day before and until a few hours before the study, only clear liquids will be permitted (water, herbal teas, filtered fat-free broths, or clear isotonic drinks).
• Medication: As a general rule, you should maintain your usual medication taking it with a small sip of water. However, this must be consulted with your doctor beforehand, especially if you take medication for diabetes (due to the prolonged fasting).
• Clothing and Accessories: It is recommended to attend with comfortable and easy-to-remove clothing, as you will need to put on a hospital gown. It is strictly necessary to remove any metallic objects, such as jewelry, piercings, watches, belts, or garments with zippers and clasps, as metal interferes with the CT images.
• Specific Requirements: For the test to be successful, the colon must be completely free of stool. The standard protocol includes:

– Following a low-residue diet (no fiber, fruits, vegetables, legumes, or whole grains) for 2 or 3 days before.

– On the day before the test, maintaining an exclusive clear liquid diet.

– Taking a specific laxative or evacuant solution at home the day before, following the instructions provided by your medical center exactly.

– In some cases, you will be instructed to take a special oral contrast in the days before to "tag" any small remaining stool in the intestine.

– As sedation is not used (unlike traditional colonoscopy), it is not mandatory to attend accompanied by an adult, and you will be able to return home independently.

• Mandatory requirement: If there is any possibility of being pregnant, it is strictly mandatory to report it before the test.*

• Expected discomfort or pain from the test: To expand the colon and correctly visualize its interior, air or carbon dioxide (CO₂) will be introduced through the rectum using a small probe. This can cause a significant feeling of bloating, gas, abdominal pressure, and mild to moderate cramps. These discomforts are temporary and subside quickly as the gas is naturally expelled after the procedure is completed.