Magnetic Resonance Arthrography Scan

What is magnetic resonance arthrography?

Magnetic resonance arthrography (MRA) is an imaging test widely used to look at the joints, such as hip, shoulder or wrist.

MRA is similar to magnetic resonance imaging (MRI), but shows better images. A contrast solution called gadolinium is given to swell the joint, outline joint structures and show any soft tissue tears and defects.

An MRA scan is a good way to look at swollen joints and can be done for any joint.

Why do you need magnetic resonance arthrography?

An MRA is designed to diagnose problems with a joint with the use of the contrast agent.

The contrast agent improves the view of the joint structures and allows better evaluation of any joint abnormalities.

What are the risks and complications of magnetic resonance arthrography?

Some MRA risks include:

• An undetected metal implant which may be affected by the strong magnetic field.
• Possible effects on early pregnancy. MRA is generally avoided in the first 12 weeks of pregnancy. Unless there is a strong medical reason to use MRA, your doctor may use other methods of imaging, such as ultrasound, on you if you are pregnant.

How do you prepare for magnetic resonance arthrography?

Before entering the scanning room, you should remove all metallic items including magnetic strips (such as those in bank or credit cards).

The strong magnetic field in the MRI will pull on any ferromagnetic metal object implanted in the body. The presence of metal will also degrade the MRI image.

You will need to take note of the following:

• Surgical staples, plates, pins and screws. These pose no risk if they have been in place for more than 4 - 6 weeks. If there is doubt, your doctor may use X-rays to verify the presence of any metal in your body or head.
• Make-up or sprays. You are discouraged to apply these products on your body or hair as they may contain metallic dust and affect the images.
• Pre-examination questionnaire. You will be asked to fill this in to ensure that any significant medical history is recorded and the staff is fully aware of any metal that may be in your body
• Claustrophobia. If you are claustrophobic, sedation may be required. Do highlight this to your doctor or radiologist for further instructions to be given.

What can you expect in magnetic resonance arthrography?

MRA is a completely non-invasive procedure and there are no known side effects.

Before the procedure

You will be asked to do the following:

• Fill in the questionnaire on your medical history.
• Remove items like your wallet, watch, keys and magnetic strip cards (for example, those in ATM, credit cards) and place them in the lockers provided.
• Change to a hospital gown. (Your normal attire may contain metallic objects that will be attracted by the powerful magnet in the MRI.)

During the procedure

You can expect to go through the following process:

• You will be positioned on a padded table and slowly moved into the machine with a cylindrical chamber for the scan. The chamber is an open magnet that surrounds the body with a magnetic field.
• You will need to remain relaxed and completely still during the scan. Movement will result in unclear images. (Note: There will be faint knocking, intermittent humming and thumping sounds. Earplugs will be provided.)
• You should try to breathe normally. You should not feel any discomfort or pain. However, it is normal to experience a warm sensation in the area under examination. Do inform the staff or your doctor if it bothers you.

You may want to take note of the following:

• Voice and visual contact. You will have voice contact with the radiographer at all times and you will be monitored from the control room.
• Claustrophobia. If you are claustrophobic, sedation may be required. Do highlight this to your doctor or radiologist for further instructions to be given.

Care and recovery after magnetic resonance arthrography

Do continue to take any medication prescribed by your doctor unless otherwise directed.