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MRI (Magnetic Resonance Imaging)

What is an MRI

MRI stands for Magnetic Resonance Imaging. It is a painless diagnostic procedure that allows physicians to see detailed images of the internal structures of your body without using X-rays. It uses a large magnet, radio waves and a computer to produce images of your internal organs and structures.

How is this service performed?

Your body is composed of small particles called atoms, and hydrogen atoms, i.e. in water, make up 95% of the body. Normally, hydrogen atoms within your body spin around at random.

However, when you are placed inside a strong magnetic field, the hydrogen atoms line up and spin in the same direction as the magnetic field. When a radio wave is transmitted through the body, the hydrogen atoms give off a signal. That signal, with the aid of a computer, becomes the source of MRI information to produce two-dimensional images or three-dimensional volumes of a part of your body.

MRI scanners are noisy; there is a repetitive clicking noise that gets louder when the scanner is taking an image.

How do I access this service?

  • Your primary health care provider sends us a completed an MRI consultation form and a patient safety questionnaire.
  • The demand for an MRI is high, and the waiting period for an MRI appointment will depend many factors. Urgent requests and emergencies are prioritized. Once we receive a request for an MRI and any accompanying paperwork, we will schedule an exam date and contact your referring physician. The referring physician will notify you on your exam time and date. (This is not the case for everyone, especially in emergency situations.)

Preparing for an MRI

  • A patient safety questionnaire must be completed before an MRI can be booked.
  • This questionnaire will identify such things as surgical clips, prostheses, metal implants or any other metal objects in your body. The information will enable MRI personnel to determine whether or not to proceed with the MRI exam. This information will be reviewed with you prior to your exam.
  • You may be required to fast (not eat) 4 hours before your MRI. You may also be required to drink a prepared drink before your exam.
  • Please arrive 30 minutes before your scheduled appointment time to allow time for preparation.
  • Patients will sometimes receive an injection of a colourless and very safe intravenous (IV) contrast liquid to improve the visibility of a particular tissue that is relevant to the scan.
  • We need to know about metal anywhere in or on your body because the magnet is never turned off, and just by entering the scan room you are in the magnetic field.
  • Certain metallic devices interfere with the scan, and their presence during the scan may cause injury to you. It is very important for us to know if you have a pacemaker or other implanted electrical device, a history of heart or brain surgery, cerebral aneurysm clips, shrapnel, or a history of getting metal fragments in your eyes. For this reason, you will be required to change into a provided hospital gown for all MRI exams.
  • Please remove medication patches prior to scan as some transdermal patches containing aluminum or other metal in their non-adhesive backing shouldn't be worn during MRI because of skin burn risk.
  • Please remove any glucose monitor (CGM) devices. Remember, all of the components of your CGM or monitoring system could be damaged and must not be exposed to X-rays, CT scans, MRI, any radiation and/or strong electromagnetic fields.
  • Please leave your valuables at home, including jewelry, to prevent it from being lost or stolen, for they have to be removed prior to entering the scan room.
  • Please let us know if you need interpreting services, this can be arranged for you.
  • If you experience anxiety related to claustrophobia, your doctor may prescribe an oral medication for you to take with you for your MRI appointment.

During an MRI scan

  • Once in the scanner, the MRI technologist will communicate with the patient via the intercom to make sure that they are comfortable. They will not start the scan until the patient is ready.
  • During the scan, it is vital to stay still. Any movement will disrupt the images, much like a camera trying to take a picture of a moving object. Loud clanging noises will come from the scanner. This is perfectly normal. Depending on the images, at times it may be necessary for the person to hold their breath.
  • If the patient feels uncomfortable during the procedure, they can speak to the MRI technologist via the intercom.

Risks or Complications

  • Rare chance of allergic reaction to contrast media (dye).
  • Inform your doctor or the technologist of any allergies or if you have diabetes, asthma, kidney problems, or if you are or might be pregnant.

How long will an MRI take?

An MRI will take anywhere from 30 minutes to 2 hours, depending on the area being scanned.

If your child has been sedated for their procedure

If your child has been sedated in order to do the necessary exam, he/she will be kept at the hospital until it is felt that he/she can be discharged. Once your child is okay to leave the hospital, he/she may exhibit some symptoms of this sedation for the next few hours.

  • Foods and Fluids: If your child seems fully awake and alert, usual foods and fluids may be given but avoid large chunky foods, such as hot dogs.
  • Activity: Your child's coordination, balance and perception may be affected. It is advised that he/she be carefully supervised for a few hours and to avoid climbing of any kind or descending stairs. Watching videos or reading are good activities to do with your child.

Facilities and programs offering this service:

Facilities and programs offering this service:
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