A computed tomography (CT) scan, also called a CAT scan, is a type of imaging tool that uses special x-ray equipment to create cross-sectional views of the inside of the body. A CT scan may be used in the diagnosis of irritable bowel syndrome (IBS), particularly if the patient is complaining of abdominal pain.1
Because there is no single definitive test to diagnose IBS, physicians use a variety of tests to determine the cause of a patient’s symptoms. IBS symptoms, such as diarrhea, constipation, abdominal pain, bloating, nausea and gas, can be caused by a number of conditions. Health care professionals may use several tests to rule out other conditions before determining a diagnosis of IBS.2 In the case of IBS, a CT scan would be normal.
CT scans for diagnosing conditions
The human body has many organs in the abdominal cavity, including organs of the gastrointestinal, endocrine, reproductive and urinary systems. A CT scan can be used to assess these organs for tumors, injuries, infections, internal bleeding, blood clots, blockages or obstructions, unexplained abdominal pain, or other conditions. A CT scan is often used after other imagining or screening tools have proven inconclusive, such as an x-ray.3,4
What to expect from CT scans
During a CT scan, the patient lies still on a table while the table passes through the center of a large x-ray machine. The patient is asked to remove any piercings or jewelry and is dressed in a hospital gown for the procedure, and pillows or straps may be used to prevent movement during the imaging process.
In some cases, a contrast agent is administered. Contrast agents are a dye that allows the different parts of the patient’s body to be seen more clearly on the x-ray. Contrast agents may be administered intravenously (IV) or through ingestion by having the patient drink a contrast liquid. If the CT scan is done with contrast, the patient will be asked not to eat anything prior to the exam. Clear liquids are permissible.
As the x-ray images are being taken, the patient is asked to remain still in order to ensure clear images. In addition, the patient may be asked to hold their breath during certain times.
Risks of a CT scan
A CT scan uses x-ray, which exposes the patient to a small amount of radiation. Any concerns about the radiation exposure should be discussed with a health care professional. In addition, if the patient is pregnant or suspects she may be pregnant, the physician should be notified as radiation exposure during pregnancy may lead to birth defects.
If a contrast agent is used, there is a small risk of an allergic reaction to the compound. Patients with allergies to any medications should report those to their doctor.3
Other IBS tests
There are a number of diagnostic tests that may be used to diagnose IBS because there is no single test that confirms the condition. Many of the tests confirm that other conditions or diseases do not cause the patient’s symptoms. Other tests that are commonly used to diagnose IBS include a physical exam with a symptom history, stool analysis, blood tests, breath tests, a colonoscopy or sigmoidoscopy and a lower GI series.