A contrast enema is a medical imaging procedure that uses X-ray technology to examine the rectum and colon. By introducing a special liquid, doctors can visualize internal structures and identify various conditions affecting the large intestine. This procedure provides detailed images to aid in understanding digestive health.
What is a Contrast Enema
A contrast enema involves introducing a contrast material into the rectum and colon, which then coats the inner lining of these organs. This material is typically barium sulfate, a milky-white substance, or sometimes a clear, water-soluble iodine solution. The contrast material absorbs X-rays, making the transparent soft tissues of the digestive tract visible on imaging scans.
The imaging process uses fluoroscopy, a type of X-ray that shows real-time organ movement, similar to a video. As the contrast material fills the colon, the radiologist observes its flow and the shape of the intestinal walls. This allows for the detection of structural abnormalities or other issues within the large intestine. Sometimes, after the barium, air is also introduced into the colon to expand it, providing a clearer, double-contrast view.
Why a Contrast Enema is Performed
Healthcare providers recommend a contrast enema to investigate unexplained symptoms affecting the large intestine. These symptoms can include abdominal pain, persistent changes in bowel habits, or rectal bleeding.
This diagnostic tool is used to detect several specific conditions within the colon and rectum. It can reveal inflammatory bowel diseases like Crohn’s disease and ulcerative colitis, which cause inflammation and ulcerations. Additionally, a contrast enema can identify polyps, which are abnormal growths, and diverticula, which are small pouches that can form in the intestinal wall. It also helps in diagnosing strictures, which are narrowed areas, or other structural problems, and can assist in the detection of tumors or blockages.
Preparing for and During the Procedure
Preparation for a contrast enema is essential to ensure clear images of the colon. Patients are instructed to follow a clear liquid diet for one to three days before the procedure, avoiding solid foods. This diet includes clear broths, gelatin, and water, but excludes red or purple liquids.
Bowel cleansing is also part of the preparation, involving laxatives or enemas taken the day before. Specific instructions are provided by the healthcare team; adhering to them precisely is important for the test’s accuracy. Patients are asked to avoid eating or drinking for a certain period before the appointment.
Upon arrival, patients change into a hospital gown and lie on an X-ray table, initially on their side. A small, lubricated tube is gently inserted into the rectum. During filling, patients may experience fullness, pressure, or a strong urge to have a bowel movement, and some mild cramping. The radiologist takes X-ray images from various angles, asking the patient to change positions. The procedure takes between 30 and 60 minutes.
After Your Contrast Enema
Immediately after the contrast enema, the tube is removed, and the patient is directed to a restroom to expel the contrast material. It is normal to have several bowel movements as the body eliminates the liquid. For a few days following the procedure, if barium was used, stools may appear white or light-colored, a normal effect.
Drinking plenty of fluids after the enema is encouraged to help flush out any remaining contrast material and prevent constipation, which can occur. Patients can return to their normal diet and activities soon after the test, unless otherwise advised. The radiologist reviews the images, and the results are sent to the referring doctor within a few days to a week. Your healthcare provider then discusses the findings and any next steps with you.