A pelvis MRI (magnetic resonance imaging) scan is a imaging test that uses a machine with powerful magnets and radio waves to create pictures of 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.
An MRI does not use radiation. Single MRI images are called slices. The images are stored on a computer or printed on film. One exam produces dozens or sometimes hundreds of images.
MRI - pelvis; MRI - hips; Pelvic MRI with prostate probe; Magnetic resonance imaging - pelvis
How the test is performed
You may be asked to wear a hospital gown or clothing without metal fasteners. Certain types of metal can cause inaccurate images.
You lie on your back on a narrow table. The table slides into the middle of the MRI machine.
Small devices, called coils, may be placed around your hip area. These devices help send and receive the radio waves, and improve the quality of the images. If pictures of the prostate and rectum are needed, a small coil will be placed into your rectum. This coil must stay in place for about 30 minutes while the images are taken.
Some exams require a special dye called contrast media. The dye is usually given before the test through a vein (IV) in your hand or forearm. The dye helps the radiologist see certain areas more clearly.
During the MRI, the person who operates the machine will watch you from another room. The test most often lasts 30 to 60 minutes, but may take longer.
How to prepare for the test
You may be asked not to eat or drink anything for 4 to 6 hours before the scan.
Tell your doctor if you are afraid of close spaces (have claustrophobia). You may be given a medicine to help you relax and be less anxious. Or your doctor may suggest an open MRI in which the machine is not as close to the body.
Before the test, tell your health care provider if you have:
Brain aneurysm clips
Artificial heart valves
Heart defibrillator or pacemaker
Inner ear (cochlear) implants
Kidney disease or dialysis (you may not be able to receive contrast)
Worked with sheet metal in the past (you may need tests to check for metal pieces in your eyes)
Because the MRI contains strong magnets, metal objects are not allowed into the room with the MRI scanner:
Pens, pocketknives, and eyeglasses may fly across the room.
Items such as jewelry, watches, credit cards, and hearing aids can be damaged.
Pins, hairpins, metal zippers, and similar metallic items can distort the images.
Removable dental work should be taken out just before the scan.
How the test will feel
An MRI exam causes no pain. If you have difficulty lying still or are very nervous, you may be given a medicine to relax you. Too much movement can blur MRI images and cause errors.
The table may be hard or cold, but you can request a blanket or pillow. The machine produces loud thumping and humming noises when turned on. You can wear ear plugs to help reduce the noise.
An intercom in the room allows you to speak to someone at any time. Some MRIs have televisions and special headphones that you can use to help the time pass.
There is no recovery time, unless you were given a medicine to relax. After an MRI scan, you can resume your normal diet, activity, and medications.
Why the test is performed
This test may be done if a female has any of the following signs or symptoms:
Abnormal vaginal bleeding
A mass in the pelvis (felt during a pelvic exam or seenon another imaging test)
A pelvic mass that occurs during pregnancy
Endometriosis (usually only done after ultrasound)
Pain in the lower belly (abdominal) area
Unexplained infertility (usually only done after ultrasound)
Unexplained pelvic pain (usually only done after ultrasound)
This test may be done if a male has any of the following signs or symptoms:
Lumps or swelling in the testicles or scrotum
Undescended testicle (unable to be seen using ultrasound)
Unexplained pelvic or lower abdominal pain
Unexplained urination problems, including trouble starting or stopping urinating
A pelvic MRI may be done in both males and females who have:
Abnormal findings on an x-ray of the pelvis
Birth defects of the hips
Injury or trauma to the hip area
Unexplained hip pain
A pelvic MRI is also frequently done to see if certain cancers have spread to other areas of the body. This is called staging. Staging helps guide future treatment and follow-up and gives you some idea of what to expect in the future. A pelvic MRI may be used to help stage cervical, uterine, bladder, rectal, prostate and testicular cancers.
A normal result means your pelvic area appears normal.
Abnormal results in both males and females may be due to:
Birth defects of the hip joint
Consult your health care provider with any questions and concerns.
What the risks are
MRI contains no radiation. To date, no side effects from the magnetic fields and radio waves have been reported.
The most common type of contrast (dye) used is gadolinium. It is very safe. Allergic reactions to the substance rarely occur. But gadolinium can be harmful to patients with kidney problems who require dialysis. If you have kidney problems, tell your health care provider before the test
The strong magnetic fields created during an MRI can cause heart pacemakers and other implants to not work as well. It can also cause a piece of metal inside your body to move or shift.
Tests that may be done instead of a pelvic MRI include:
A CT scan may be done in emergency cases, since it is faster and usually available right in the emergency room.
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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.