What is an MRI arthrogram?
An MRI arthrogram is two-part procedure, involving fluoroscopy and MRI. First, a special type of X-ray technology, called fluoroscopy, is used to take pictures of the joint after a contrast material has been injected into it. This allows the radiologist to see the soft tissue structure of the joint. The joint is then examined with MRI, a routine diagnostic imaging procedure that uses a large magnet, radio waves, and a computer to produce 2- and 3- dimensional images of the body's organs, tissues and bones.
An MRI arthrogram can be done on the following joints:
Why might an MRI arthrogram be needed?
Your physician may request an MRI arthrogram when a problem with your child's joint cartilage is suspected. An MRI arthrogram may be more useful than a regular x-ray because it shows the surface of soft tissues lining your child's joint as well as the bones.
MRI is done in conjunction with an arthrogram, as it can obtain specific diagnostic information not provided by the arthrogram.
How should I prepare my child for the MRI arthrogram?
- There is no special restriction on diet or activity prior to an MRI arthrogram.
- It is helpful to give your child a simple explanation as to why the test is needed and assure him that you will be there for him entire time. However, you cannot be in the room during the first part of the arthrogram if you are pregnant. If you are pregnant, please bring the other parent or a trusted caregiver.
- You may want to bring your child's favorite book, toy or comforting object to use during waiting times.
- If your child will be using the video goggles or listening to music during the MRI, you may want to bring a favorite DVD or an iPod from home. The department also has a collection of movies available.
What should I bring my child to the hospital?
When you arrive, please go to the Radiology check-in desk on the second floor of the main hospital. An ambulatory service representative will check your child in and verify his registration information.
We will give you an MRI safety screening questionnaire to fill out for your child:
- This form will ensure that your child can be safely imaged in MRI.
- If you plan to accompany your child into the scanner room, you must also fill out a form for yourself.
- Please bring supporting documentation of MRI safety if you or your child have had any surgical implants or devices. Delays may result if devices need to be researched. Some exams may need to be cancelled if required MRI safety information cannot be obtained.
After you check in, a radiologist will:
- Explain the procedure to you and your child
- Answer your questions
- Obtain your written consent
What happens during the arthrogram?
You and your child will be taken to the procedure room, where the fluoroscope will be used to take x-rays. Your child will need to sit or lie on the fluoroscopy table. The radiologist will:
- mark and initial the area on your child's body that's being examined with a felt pen
- cleanse the injection area on his skin with a sterile soap
- Numb the area around his joint by injecting a local anesthetic (your child will feel a numbing sensation)
- Inject the contrast material and a local anesthetic into your child's joint using a needle. After a small amount of liquid has been injected, the needle will be removed.
After the injection, your child may be asked to move the joint around so that the contrast can be distributed evenly throughout the joint. This portion of the procedure generally takes about 20 minutes.
Will my child feel anything during the arthrogram?
The injection of the anesthetic may cause your child some discomfort, but it's minimized through the use of a numbing agent.
Your child may have some mild pain, tenderness and swelling in the joint after the exam. You may also hear a grating, clicking or cracking sound when the joint is moved. This is normal and goes away in about 24 hours.
What happens after the arthrogram?
When the arthrogram is complete, you will be taken to the MRI check-in desk for the MRI portion of the imaging exam.
What is an MRI scanner and how does it work?
An MRI scanner is a large, tube-shaped magnet that provides a strong magnetic field around your child. A radiofrequency coil is placed over the body part that is to be imaged. The magnetic field, along with applied radiofrequency waves, temporarily alters the alignment of hydrogen protons found in water molecules within the body. Computers construct the images based on the radiofrequency signals emitted by the protons.
What happens during the MRI scan?
After the arthrogram, your child is moved to an MRI room where additional imaging is performed. When your child is brought into the scanner room:
- The MRI technologist positions him on the scanning bed. The inside of an MRI machine looks like a tunnel. It is necessary for the body part that will be scanned to be in the center of the scanner, so the technologist will move the scanner bed into the tunnel until it is appropriately positioned.
- We give your child earplugs to protect his or her ears because the MRI machine makes loud pulsing or knocking sounds.
- The technologist asks your child to lie still while the scan is in progress.
An MRI technologist performs your child's scan. You may stay in the scanner room with your child unless the MRI safety screening questionnaire finds that it is not safe for you to do so. You are also given earplugs to wear in the room.
MRI scans consist of several sequences of a few minutes duration each that cumulatively take anywhere from 20 to 90 minutes, depending on the information required by the radiologist and your physician. We give you a more specific time frame before the scan begins.
Will my child feel anything during the MRI scan?
An MRI is loud at times, but painless. The MRI scanner takes pictures without touching the body.
What does an MRI sound like?
MR makes music!
What happens after the MRI arthrogram?
When the MRI arthrogram is done, your child will be ready to go home. The radiologist reviews the images and creates a report of the findings and diagnosis for your referring doctor.
How do I learn the results of the MRI arthrogram?
The radiologist's report will be sent to the physician who requested the exam and your child's doctor will then discuss the results with you.
What are the risks of MRI?
Years of experience have shown no known harmful effects from the magnetic fields and radiofrequency pulses emitted by the MRI machine.