You must be still during the exam, because movement causes blurred images. You may be told to hold your breath for short periods of time. In many cases, an abdominal CT is done with a pelvis CT. The scan should take less than 30 minutes. You need to have a special dye, called contrast, put into your body before some exams. Contrast helps certain areas show up better on the x-rays. Contrast can be given through a vein (IV) in your hand or forearm. If contrast is used, you may also be asked not to eat or drink anything for 4 to 6 hours before the test.