A computed tomography (CT) scan of the pelvis is an imaging method that uses x-rays to create cross-sectional pictures of the the area between the hip bones. This part of the body is called the pelvic area.
Structures inside and near the pelvis include the bladder, prostate and other male reproductive organs, female reproductive organs, lymph nodes, and pelvic bones.
Single CT images are called slices. The images are stored on a computer, viewed on a monitor, or printed on film. Three-dimensional models of the body area can be created by stacking the slices together.
You are asked to lie on a narrow table that slides into the center of the CT scanner.
Once you are inside the scanner, the machine's x-ray beam rotates around you.
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.
The scan should take less than 30 minutes.
How to prepare for the test
Certain exams require a special dye, called contrast media, to be delivered into the body before the test starts. The contrast helps certain areas show up better on the x-rays.
Contrast can be given through a vein (IV) in your hand or forearm. Or you may be asked to drink a liquid form of contrast. If contrast is used, you may also be asked not to eat or drink anything for 4 to 6 hours before the test.
Let your doctor know if you have ever had a reaction to contrast. You may need to take medicines before the test in order to safely receive this substance.
Before receiving the contrast, tell your health care provider if you take the diabetes medication metformin (Glucophage) because you may need to take extra precautions.
If you weigh more than 300 pounds, find out if the CT machine has a weight limit. Too much weight can damage the scanner's working parts.
You will be asked to remove jewelry and wear a hospital gown during the study.
How the test will feel
Some people may have discomfort from lying on the hard table.
Contrast given through an IV may cause a slight burning sensation, a metallic taste in the mouth, and a warm flushing of the body. These sensations are normal and usually go away within a few seconds.
Why the test is performed
CT rapidly creates detailed pictures of the body, including the pelvis and areas near the pelvis. The test may be used to diagnose or detect:
Masses or tumors, including cancer
The cause of pelvic pain
Injury to the pelvis
This test may also help:
Guide a surgeon to the right area during a biopsy or other procedures
CT scans do expose you to more radiation than regular x-rays. Having many x-rays or CT scans over time may increase your risk of cancer. But the risk from any one scan is small. You and your doctor should weigh this risk against the benefits of getting a correct diagnosis for a medical problem.
Some people have allergies to contrast dye. Let your doctor know if you have ever had an allergic reaction to injected contrast dye.
The most common type of contrast given into a vein contains iodine. If a person with an iodine allergy is given this type of contrast, nausea or vomiting,sneezing, itching,or hives may occur.
If you absolutely must be given such contrast, your doctor may give you antihistamines (such as Benadryl) or steroids before the test.
The kidneys help remove iodine out of the body. Those with kidney disease or diabetes may need to receive extra fluids after the test to help flush the iodine out of the body.
In rare cases, the dye causes a life-threatening allergic response called anaphylaxis. If you have any trouble breathing during the test, you should tell the scanner operator right away. Scanners come with an intercom and speakers, so the operator can hear you at all times.
Childs DC, Dalrymple NC. Female reproductive system. In: Dalrymple NC, Leyendecker JR, Oliphant M. Problem Solving in Abdominal Imaging. Philadelphia, PA: Elsevier Mosby; 2009:chap 21.
Dalrymple, NC. Ureters, bladder, and urethra. In: Dalrymple NC, Leyendecker JR, Oliphant M. Problem Solving in Abdominal Imaging. Philadelphia, PA: Elsevier Mosby; 2009:chap 19.
Gjelsteen AC. CT, MRI, PET, PET/CT, and ultrasound in the evaluation of obstetric and gynecologic patients. Surg Clin North Am. April 2008; 88(2): 361-90, vii.
Zarka AI, Jung AJ, Dalrymple NC. Male reproductive system. In: Dalrymple NC, Leyendecker JR, Oliphant M. Problem Solving in Abdominal Imaging. Philadelphia, PA: Elsevier Mosby; 2009:chap 20.
Ken Levin, MD, private practice specializing in Radiology and Nuclear Medicine, Allentown, PA. Review provided by VeriMed Healthcare Network. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.