Diseases & Conditions

Abdominal Computed Tomography - Abdominal CT Scan

Overview & Description

Computed tomography, also called CT, is a computer-aided X-ray technique. An abdominal CT scan produces detailed cross-sectional views of sections of the abdomen. This could be thought of as similar to taking pictures of slices of bread to see the different parts of the loaf.

Who is a candidate for the test?

An abdominal CT scan is recommended for people who have suspected diseases or conditions of the abdomen. A doctor may advise a person to have this test if he or she has one of the following conditions:

  • abdominal pain for unknown reasons
  • abdominal trauma
  • abnormal findings on X-ray, ultrasound, or other studies of the abdomen
  • suspected abdominal cancer
  • suspected liver, kidney, gallbladder, or bowel disease
  • undiagnosed fevers, to make sure an abscess, or pocket of pus, is not present
  • How is the test performed?

    A person having a CT scan will need to undress and put on an exam gown. Next, he or she will lie on a narrow table. The table will slide through a machine that looks like a doughnut. This is called the gantry. While the person is in the gantry, an X-ray tube takes pictures of different parts of the person's abdomen to create computer-generated X-ray images.

    Some types of CT exams require the person to receive an iodinated dye, which makes some tissues show up better. The dye, also called contrast solution, may be injected into the person's vein or may be given as a drink. Each X-ray emits a very low dose of radiation and takes only seconds. The whole test lasts about 45 minutes.

    After the exam, a technician will view the pictures to make sure they can be seen clearly. If they are OK, the person can usually get dressed and is free to leave.

    Preparation & Expectations

    What is involved in preparation for the test?

    People will be asked about allergies to iodine, which is in the dye. Women will also be asked if they may be pregnant. All jewelry and metal objects must be removed to avoid interfering with the images. This exam can cause claustrophobia, which is the uncomfortable feeling you may have from being in a small place. A claustrophobic person may require a sedative before the exam. X-ray department staff will tell the person if other preparations are needed.

    Results and Values

    What do the test results mean?

    A CT scan provides a direct image of soft tissue structures such as the liver, lung, spleen, pancreas, lymph nodes, and fatty tissues. CT is also good for identifying and tracking large abnormalities such as tumors. The pictures can reveal many different diseases and conditions. Examples include cancer, organ damage, abnormal blood vessels, infections, kidney stones, and bleeding. The doctor will discuss the results of the exam with the person.


    Author:James Compton, MD
    Date Written:
    Editor:Crist, Gayle P., MS, BA
    Edit Date:08/20/02
    Reviewer:Carlos Herrera, MD
    Date Reviewed:08/20/01