Virtual colonoscopy

Virtual colonoscopy or colonoscanner is a technology that uses X-rays. This procedure is painless and allows to visualize the colon externally. It makes it possible to visualize the colon without colonoscopy. The technique of virtual colonoscopy can be proposed in case of medical contraindication to video colonoscopy, in case of positive test for occult bleeding in the stools. It allows the detection of polyps >5 mm and colon cancers. This technique also makes it possible to analyze other abdominal organs (liver, spleen, pancreas, kidneys, aorta...).

Principle of the examination

The scanner is a very wide ring-shaped device that rotates at high frequency. This device is equipped with X-ray transmitters and receivers that capture them to form contrasting images. Optimal data acquisition requires holding your breath one or more times for 25 to 35 seconds. During the examination the doctor will also breathe air several times to take the images. The images will then be reconstructed on a console equipped with software where they will be analyzed in different cutting planes.


You are invited three days before the exam to follow a residue-free diet (see your doctor’s instructions). Two days before the exam you should take the laxative prescribed by your doctor. The day before the examination you need to completely empty the intestine by ingesting the washing fluid prescribed by your doctor. The goal is to present yourself on the day of the exam with a clean, fasting colon (do not eat, drink and smoke).

Residue-free diet
You can eat :


Cooked fruit only (apple, pear, plum, apricot, peach).

Meat, fish, eggs

Low-fat meat (ham, dried meat, turkey, etc.), fish, eggs.


White rice, white pasta, polenta, semolina, flour, potatoes, rusks, toasted white bread.


Soups only based on broths (without vegetables).

Dairy products

Milk in preparations, yogurt, fresh cheese, hard cheeses (Gruyère, Emmenthal, Gouda, etc.), soft cheeses (Camembert, Chèvre, etc.).

Sweet products

Jelly, sugar, honey, meringues, dry biscuits (without almonds, etc.).


Oil, butter, margarine, cream.


Salt, aromatics, herbs, lemon, vinegar.


Still water, tea, herbal teas, light coffee in moderation.

You can’t eat : Vegetables (neither cooked nor raw ), Jams, Fries, Spices, Alcohol.

Conduct of the examination

You are taken care of by a member of the medical team who accompanies you in the examination room. You are lying on your back or stomach on a table and are asked to remain still while the table moves through the ring of the scanner that delivers the X-rays.

  • Your rectum is equipped with a thin, flexible balloon probe.
  • An IV catheter is placed to inject you with a spasmolytic and contrast medium.
  • The doctor blows CO2 into the colon using a breather to dilate it.
  • He performs the scanner in two positions (on the stomach and on the back) at a low dose of irradiation, in order to mobilize any residues.
  • Once the examination is complete, the doctor removes the probe.

The exam lasts +/- 30 minutes. 30 minutes after the exam, you can resume your activities.


The examination is contraindicated in case of pregnancy. Precautions: If you suffer from allergy or glaucoma, please refer it to the doctor before the examination.

In Belgium, the legislation does not allow the reimbursement of scanners installed in an out-of-hospital context. The examination is therefore not covered by Belgian social security, but can be reimbursed by foreign insurance schemes or possibly by a private supplementary insurance scheme. A lump sum is requested according to the type of examination. A receipt for the amount paid and the various documents necessary for reimbursement by insurance will be issued. This information will be reminded by the secretariat during your appointment.