MRI

mri machine

Magnetic resonance imaging (MRI) is a safe, painless and non-invasive way of taking pictures of soft tissues of the body. These images will provide your physician or specialist with very clear and detailed pictures of the body part they want greater detail on — whether head, abdomen or joint.

At Markham Stouffville Hospital, we have a 3.0 Tesla Siemens MRI scanner and a 1.5 Tesla Phillips MRI scanner. These pieces of equipment are the latest in MRI technology and make scans easier and safer for patients as they can accommodate more weight.

MRI allows your doctor or specialist to diagnose medical problems inside your body without radiation or surgery. Using a large magnet, imaging coils and a computer we can produce accurate images of any part of your body. Non-ionizing radiation is used in MRI (i.e. radio waves and magnetism).

When a completed requisition is received, a radiologist will prioritize your request based on the urgency of your situation and then your appointment will be scheduled. A pre-screening questionnaire is completed by your referring physician and reviewed by staff prior to your booking. A detailed form is completed by the patient and reviewed by the technologist upon arrival for their appointment to ensure that it is safe for you to have an MRI.

MRI is not a suitable diagnostic technique for anyone with:

  • A pacemaker
  • Metallic objects inside their body (dental fillings and orthopaedic hardware are fine)
  • Inner ear implants (depending on manufacturer/make/model numbers)
  • Some aneurysm clips (need to be investigated)
  • Cardiac implants (need to be investigated)

What you should know

Special arrangements are not typically needed if you normally would drive yourself to and from your appointment.  However, if you will have taken any sedatives on the day of your MRI scan we do ask that you make arrangements for an alternate driver to assist you in getting home safely.  You may eat or drink as you normally would on the day of your scan.  Continue to use any prescription medicines. 

The only exception is if your MRI has been requested for any abdominal or pelvic scan, you are required to fast for six hours prior to your appointment, avoiding food or water. If you have been scheduled for an Enterogram (an MRI of the small bowel), you will be required to start your preparation for the exam the night before. Download the Enterogram preparation sheet here. For this exam we strongly suggest you plan to go directly home after the procedure.

Before you visit

Please arrive on time for your appointment. You will be given your arrival time and preparation instructions when you book your test. Please bring your health card.

 During your visit

During your MRI, you will hear a series of sequences. Each sequence creates noise. Earplugs will be given to protect your ears as well as an emergency call ball if you have any issues. Once the pictures start the technologist will be watching you through a window during the entire exam and talking with you over an intercom speaker. Some instructions are pre-recorded in English, and there is also a library of other languages that may be selected from to better support our patients during their scan.

You may be required to have a contrast solution administered by an IV during your MRI. This contrast helps the radiologist to highlight the area you are having scanned. It is very rare to have a reaction to this solution and it will improve the visibility and accuracy of your MRI scan.

An MRI takes approximately 20 to 40 minutes to complete.

 After your visit

An MRI has no known side effects or risks and is safe for children as well. If your physician has prescribed you with a sedative for claustrophobia during your MRI, please arrange a drive to and from your MRI appointment.

 Care providers

An MRI is performed by is performed by a medical radiation technologist (MRT) specialized in MRI technology.

Frequently Asked Questions

What is the thumping or bumping noise I hear inside the chamber?

These are normal noises that are not harmful in any way and let you know the machine is working. Ear protection will be provided.

Will it hurt? Will I feel uncomfortable?

An MRI scan is completely painless. The only difficult aspect is the necessity to lie as still as possible for the duration of the scan. Depending on the part of the body being examined, we might have to inject a “contrast” solution to give the radiologist additional information. There are few or no side effects of this solution, and the injection is just like any other you might have had.

What happens if I am claustrophobic, or get anxious during the MRI scan?

If at any time you are uncomfortable, or feel yourself getting upset, you can talk to the technologist through the two-way intercom. You will have an emergency call bell. Mirrors or eye covers can be provided. There is a fan inside the bore for air flow. Remember the magnet bore is open at both ends. Nothing will close on you. If you are clinically claustrophobic, tell your referring doctor or specialist. He or she can even provide you with a sedative to bring along if you need one. If your physician has prescribed a sedative, please ensure that you have someone who can drive you home.

What happens if I don't fit inside the MRI chamber?

We have two scanners – one has a 60cm bore and can accommodate patients up to 450lbs. Our newer scanner has a 70cm bore and can accommodate patients up to 550lbs. Our new scanner is also a stronger (3T) magnet and it is too strong for certain surgical implants so this is a consideration. It is rare that patients cannot be accommodated.