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Computerized tomography (CT) enterography is a type of CT scan. It takes images of the abdomen and pelvis and is specially designed to provide detailed images of the small intestine. The small intestine also is called the small bowel. You may hear CT enterography referred to as a CT scan of the small bowel or a CT scan of the small intestine.
CT enterography is different from a standard CT scan of the abdomen and pelvis because the exam is designed specifically to study the small intestine. It can help find swelling and irritation, bleeding, tumors, and complications of Crohn's disease.
CT enterography also is different from CT enteroclysis and CT colonography, also called virtual colonoscopy. CT enteroclysis requires a tube to be passed through the nose into the small intestine before taking images. CT colonography looks mainly at the large intestine, also called the colon.
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Your care team may recommend CT enterography to look for concerns in your small intestine. The test can help find:
- Crohn's disease and other inflammation. CT enterography can show signs of swelling and irritation in the small intestine, such as thickening of the bowel wall. Crohn's disease is a type of inflammatory bowel disease. CT enterography can show where Crohn's disease is, how active it is and whether it has caused complications. These may include irregular tunnels called fistulas, pockets of infection called abscesses and narrowed areas called strictures.
- Bleeding. CT enterography can help find the source of bleeding in the small intestine.
- Tumors. The test can help find masses or tumors in the small intestine, including tumors caused by small bowel cancer.
CT enterography may be used for some bowel obstructions that come and go or develop more slowly. If your healthcare professional suspects a sudden bowel obstruction, other types of CT scans may be used instead of CT enterography. Your care team also may suggest other types of CT scans when there is reduced blood flow in the intestine. This is called intestinal ischemia. Other CT scans also may be used when there is a hole in the intestine, called a perforation.
المخاطر
Radiation
CT enterography uses a small amount of energy called radiation. It uses more radiation than a plain X-ray because a CT scan gathers information that is more detailed.
The radiation used in CT scans may slightly increase the lifetime risk of cancer. The potential risk may increase with higher radiation doses and repeated scans. Children are more sensitive to radiation than adults.
Radiology teams use the lowest amount of radiation needed to get detailed images. The benefit of getting an accurate diagnosis generally outweighs the risks from radiation. Talk with your care team if you have questions about radiation.
Pregnancy
Tell your care team if you are pregnant or may be pregnant. CT enterography generally isn't recommended during pregnancy unless it's medically necessary. Radiation from the scan may pose a very small potential risk to the developing baby.
Contrast material
CT enterography uses two types of contrast. You drink oral contrast to fill and expand the small intestine. Iodinated contrast is injected through an intravenous (IV) line to make the bowel wall, blood vessels and nearby tissues show more clearly.
Serious reactions to oral contrast and IV iodinated contrast are rare. The oral contrast can cause short-term digestive symptoms such as nausea, cramping or diarrhea. If you have had a reaction to contrast that contains iodine, your risk of reaction may be higher.
Kidneys remove IV contrast from the body. If your kidneys aren't working well, your care team may check how well they work before giving you IV contrast.
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Follow the instructions your care team gives you to prepare for the test. In some cases, your instructions may differ from the ones described here.
Before the test, tell your care team if:
- You have had previous reactions to iodinated contrast.
- You have any other allergies or have had other bad reactions, including reactions to medicine, food or latex.
- You have kidney disease.
- You have diabetes or asthma.
- You are pregnant or think you may be pregnant.
You are asked not to eat, also called fasting, for a certain amount of time before the test. Be sure to follow all preparation instructions.
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Before the procedure
Before the scan:
- You drink oral contrast. The liquid fills and expands your small intestine so that its walls show up more clearly on CT images. An hour or so before the scan, you drink about 67 ounces (2 liters) of the liquid. The liquid is a little thicker than water. If you think you may have trouble drinking all the liquid within an hour, tell a member of the healthcare team before the test. The care team may give the liquid through a tube, although this is rare. It takes extra time to give the liquid to you through a tube.
- You have an IV placed in a vein, usually in the arm. During the scan, contrast material is injected through the IV.
- You may need to change into a hospital gown. You also may need to remove jewelry, eyeglasses or other metal objects that could affect the images.
Preparing for CT enterography takes longer than the scan because you need time to drink or get the oral contrast.
During the procedure
During CT enterography:
- You lie on your back on a narrow table that moves through the CT scanner. The scanner is shaped like a large ring. As the scanner takes pictures, you may hear buzzing or whirring sounds.
- A CT technologist operates the scanner from another room. The technologist can see and hear you, and you can talk with the technologist through an intercom. You may be asked to hold still or hold your breath for short periods. Movement can blur the images.
- During the scan, contrast material is injected through your IV. When the contrast is given, your body may feel warm for a short time. You also may notice a metallic taste in your mouth.
The CT scan itself is brief. In total, the appointment usually takes about two hours. The timing may vary depending on where you have your test done.
After the procedure
After the scan, you likely can return to your usual routine. You may be asked to wait a short time before you leave. This allows the care team to make sure you feel well after receiving the IV contrast.
The oral contrast may cause short-term cramping or diarrhea.
النتائج
A radiologist is a doctor trained to interpret imaging scans. The radiologist reviews your CT enterography images and sends a report to the healthcare team member who ordered the test.
Your care team can explain what the findings mean and how they relate to your symptoms, medical history and any other test results.
For example, for Crohn's disease, CT enterography results can help your care team decide on treatment based on the findings and whether there are complications.
التجارب السريرية
استكشِف دراسات مايو كلينك حول الاختبارات والإجراءات المخصصة للوقاية من الحالات الصحية واكتشافها وعلاجها وإدارتها.