What is Computed Tomography?

Computed Tomography or "CT" scanning is a diagnostic imaging tool that produces detailed "slices" of anatomy that when assembled create important three-dimensional organ studies.

The scans are produced by an x-ray beam that rotates around the patient. As the x-rays pass through the body they are detected by special sensors, and information from the sensors is processed by the computer into an image on a video screen. Contrast agents can also be used.

3-D CT images of  a
severe skull fracture
following a motor
vehicle accident.

CT arteriogram of
the abdominal aorta,
showing the major
branches to the
kidneys (renal

Because of its ability to precisely image internal portions of organs and separate overlapping structures, the CT scan has become the diagnostic tool used most often to diagnose a variety of problems. The CT scan may also be used rather than exploratory surgery and other painful radiological exams.

Preparing for a CT Scan

Following are some general guidelines that may apply to many of the various CT examinations. The results of your exam will be provided promptly to your physician.

If an oral or intravenous contrast agent is being used during the exam (for example in an abdominal CT scan), you may be asked to avoid food and fluids two to four hours prior to your appointment. Contrast agents given by mouth or injection help your physician see the organs inside your body and are a standard part of many exams.

Because our schedules are often tight and emergency exams can not be predicted, you may want to bring something with you to occupy your time while you wait for your test to be given.

Be sure you tell the CT technologist if you are allergic to any medication.

Click on one of the areas below for more in-depth information about specific CT procedures.

What to Expect During a CT of the Brain

What to Expect During a CT of the Chest

What to Expect During a CT of the Abdomen

When Your Child Needs a CT Scan

Magnetic Resonance Imaging

Computed Tomography


Angiography &
Interventional Radiology

Diagnostic Ultrasound

General Radiology

Nuclear Medicine


GI Radiology


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