Magnetic Resonance Imaging (MRI)

Proper preparation is important to ensure the highest-quality images. Instructions may vary depending on the type of MRI, so please follow the instructions provided by the bookings office. If you’ve been instructed to avoid eating or drinking before your MRI, you can still take your medications with a small sip of water.

We recommend wearing loose-fitting clothing that’s easy to change out of, as you will be asked to change into hospital-provided clothing to ensure safety and optimal image quality.

Plan to be at the facility for at least an hour to allow time for MR safety screening, preparation, and the scan itself. You can resume normal activities after your exam, unless advised otherwise by your healthcare provider.

Your MRI exam will be performed by a registered medical radiation technologist (MRT). MRTs are responsible for using advanced imaging and radiation techniques to provide accurate diagnostic information for your care. As both technical experts and frontline caregivers, they play a critical role in patient care, advocacy, and clinical decision-making. Click here to learn more about MRTs!

• MRI technologists are MRTs who have received extensive training in MRI physics and safety, focusing on the unique risks associated with the strong magnetic field, radiofrequency energy, and time-varying gradient fields used in MRI. They are trained to manage potential hazards such as projectile risks, heating effects, and nerve stimulation, ensuring the safety of both patients and staff throughout the MRI procedure.

A radiologist will review all of your imaging and provide a report to your referring healthcare provider. Radiologists are highly specialized physicians who play a pivotal role in diagnosing and monitoring diseases and injuries through advanced medical imaging. Their expertise is essential in guiding treatment decisions and ensuring optimal patient outcomes.

MRI technologists are responsible for screening individuals for MRI contraindications, such as implanted devices or metal fragments, and for maintaining a safe environment for both patients and staff. Due to the risks posed by the different energies associated with MRI, all patients must complete a safety screening questionnaire and verbal interview with an MRI technologist.

It is important to inform your healthcare provider and MRI technologist about any metallic implants, devices, or foreign objects in your body. Some of these may pose safety risks in the MRI environment or interfere with imaging.

To ensure your safety, the following device or implant information is required prior to booking your MRI:

• Type of device or implant

• Manufacturer and model

• Date of implantation

• Location in the body

• Any documentation or implant card, if available

Providing this information helps determine whether it is safe for you to undergo an MRI scan.

Note: If the patient is unable to answer questions about their medical history due to reasons such as cognitive impairment or language barriers, a family member who is familiar with the patient's complete medical history must be present.

CGMH requires all patients to change into hospital-provided gowns and pants for MRI exams, as some fabrics – including athletic wear – can contain hidden metallic fabrics that may cause burns. Wearing MR-safe, pocketless garments ensures safety and improves image quality. It is also important to remove any metallic items, including jewelry, watches and hair accessories (ie: pins, clips or wigs).

Note: Lockers will be available to secure your belongings; however, it’s recommended to leave valuables at home. CGMH is not responsible for personal items.

If you are wearing a medicine patch or a continuous glucose monitor, it’s important to inform the MRI technologist before your scan.

Some medicine patches contain a metallic (foil) backing that can heat up during an MRI, potentially causing burns or altering medication dosage. Continuous glucose monitors may not function correctly and could provide inaccurate readings after being exposed to the strong magnetic field. Certain brands may be safe under specific conditions.

Note: Every effort will be made to schedule your MRI at the end of your patch or monitor cycle to reduce risk and avoid interruptions, please speak to our booking's team when scheduling your appointment. In the event your patch or monitor needs to be removed, please bring extra transdermal patches and continuous glucose monitors to apply after the examination.

While modern MRI scanners are shorter and more open, some patients may still feel claustrophobic. If you’re feeling anxious, let your technologist know – they’re trained to help and are here to support you. You’ll have an emergency call bell and will be in regular contact with the technologist throughout the exam to ensure your comfort and safety. The following tips and tricks may help you complete your exam successfully:

Relaxation Techniques: Consider practicing visualization or deep breathing exercises to help you feel more at ease before and during the scan.

Listen to Music: Choose your favorite music genre or artist to listen to during your MRI to help pass the time. Focusing on the music or lyrics can help you relax and distract you from the procedure.

Communication: The technologist will be communicating with you between each sequence. They will work with you to ensure you're comfortable throughout the procedure.

Positioning: Ask if a feet-first position is possible. This may help keep your head outside the scanner and reduce feelings of claustrophobia.

Sedation and Medication Options: If you have a history of claustrophobia or have had difficulty tolerating an MRI in the past, talk to your healthcare provider about the possibility of a mild sedative to help you relax during the scan. CGMH does not provide sedation. Bring your filled prescription with you on the day of your appointment and follow the timing instructions provided by your healthcare provider or pharmacist.

Note: If you are taking sedation, you must have someone to drive you home after the procedure.

CGMH is equipped with a 70cm bore, which is wider and more spacious than older MRI systems that typically used a 60cm bore. Although a 10cm increase may not seem like much, it can make a significant difference in comfort and fit. If an MRI isn't possible, your healthcare provider will discuss other approaches that suit your needs.

MRI exams of patients with pacemakers or implantable cardioverter-defibrillators (ICDs) are not routine. Depending on the make and model, patients with such devices can be scanned safely under certain conditions. Currently, CGMH is not scanning patients who have pacemakers or ICDs.

If you are pregnant or suspect you may be, please inform your healthcare provider and MRI technologist. While pregnant patients can safely undergo a non-contrast MRI examination at any stage of pregnancy, the technologist may need to adjust certain parameters on the scanner. If your exam requires contrast your healthcare provider, in consultation with the MR radiologist, will perform a risk vs benefit assessment to determine the most appropriate course of action.

Extensive, dark, or loop-shaped tattoos - including tattooed eyeliner - may cause increased heat during the MRI.

Note: Tattoos applied within 48 hours of your MRI may smudge during the scan.

Your body is made up of countless atoms. Since the body is composed of mostly water, about 95% of these atoms are hydrogen. When placed in a strong magnetic field, these hydrogen atoms align and spin in the same direction - similar to how a compass needle points North. When radio waves are introduced, the hydrogen atoms send out signals. A computer then captures these signals and transforms them into detailed images of the specific area being examined. Click here to learn more!

CGMH houses a 1.5 Tesla (1.5T) MRI because it offers the best mix of image quality, patient comfort, and safety for the widest range of exams. The 1.5T system works well for patients with MR conditional medical implants and provides clear, detailed images of the body.

While 3T magnets are stronger, and can offer advantages for specific applications or exams, that extra power isn’t needed for most tests and can sometimes cause more image artifact or patient discomfort due to increased heating. Our 1.5T MRI provides excellent image quality and reliable results, enabling our care team to make accurate diagnoses while prioritizing patient comfort and safety.

Contrast dye is a substance used during certain MRI exams to enhance the visibility of specific areas of the body such as blood vessels, organs, joints and soft tissues. This allows radiologists to better assess the structure, integrity, and function of the area being examined.

There are different types of contrast agents used depending on the clinical history and diagnostic question:

• Oral Contrast Agents: These are ingested by the patient and are commonly used to enhance imaging of the gastrointestinal (GI) tract.
• Gadolinium-Based Contrast Agents: These substances are commonly injected into blood vessels or joints to improve the visibility of internal structures during imaging.

Although rare, allergic reactions can occur after receiving IV contrast. If you have a history of a contrast reaction, please inform your healthcare provider and MRI technologist.

If you are breastfeeding, current research shows that it is safe to continue breastfeeding after receiving MRI contrast. Please inform your technologist - they will provide you with any additional information you may need. Please click here for more information on contrast agents.