MRI

On the day of your scan, choose loose-fitting, comfortable clothing that doesn’t have metal in it. The radiographer might also ask you to wear a hospital gown during the scan.

Be sure to leave behind your phone, spare coins, dentures, eyeglasses, hearing aids, keys, underwire bra, and watch before you head to the MRI room. The powerful magnets from the MRI will damage any electrical device or bank/credit cards.

In some cases, a specialist will inject a contrast dye, called gadolinium, into a vein in your arm or hand. The dye makes it easy for the doctor to see structures in your body more clearly. It’s also good to know beforehand that when you taste something metallic in your mouth, this is due to the dye and it is normal to experience this.

You will be asked to lie on a table, and you might also be strapped in to ensure no movement during the scan. Once you’re ready, the table will then slide into the MRI machine.

The MRI machine applies a very strong magnetic field inside your body. Since it doesn’t use radiation, you do not have to worry about radiation exposure. It is important to remain still. When you move, we may not get accurate images which may impact the diagnosis.

The computer then generates a series of images from the magnetic field signals, with each image showing a thin slice of your body. The procedure takes between 20 to 90 minutes.

You will hear loud banging noises during the scan. This is caused by the movement of the magnets in the machine. If you think this will be bothersome for you, you may ask for earplugs or earmuffs to soften the loud sounds.

For this procedure, we use an MRI machine, a big tube with a powerful magnet surrounding it. There’s a table where the patient can lie down as well; this slides into the tube. Whether your body will completely be inside the machine or just a part of it depends on which body part/s need examining.

Side effects post-MRI procedure rarely happen. If any side effects do occur, it could be due to the contrast dye, which can cause nausea, headaches, and pain or burning at the point of injection in some cases. Some people may be allergic to the contrast dye as well; they can develop rashes or itchy eyes.

If your body has some reactions to the contrast material, do inform the specialist in charge.

Once the scan is complete, the images that have been created will be transferred via computer to a radiologist to read them. They will send a report to your doctor, who can then discuss the results with you.

Before you go for an MRI scan, here are some questions you need to answer to see if it's suitable for you:

• Do you have health issues or diseases your doctor should be aware of?
• Did you recently go through surgery?
• Do you have any food or medicine allergies?
• Do you have asthma?
• Are you pregnant?
• Do you have any metal-based devices in your body such as the following? (Having one or more of these may cause problems during the test.)
  • artificial heart valve
  • cochlear implant
  • drug pump
  • fillings and other dental work
  • implanted nerve stimulator
  • drug infusion pump
  • metal fragments (bullet or shrapnel)
  • metal joints or limbs
  • pacemaker or implantable cardioverter-defibrillator (ICD)
  • pins or screws
  • tattoos with ink that may contain metal.

Please discuss with your doctor if any of the above applies to you.

Due to MRI's strong magnetic field, it may not be safe if you currently have, or have previously had:

• a pacemaker or defibrillator
• an implanted electronic device
• a Cochlear implant or other inner ear implant
• an artery/vein clip, coil/vascular graft, or aneurysm clip
• a metallic foreign body to your eye.

Please discuss with your doctor if any of these applies to you.

MRI outpatient safety questionnaire [PDF 408KB]