MRI: Safety, Side Effects, and What to Know Before Your Scan

Overview

MRI stands for Magnetic Resonance Imaging. Unlike X-rays or CT scans, MRI does not use ionizing radiation. Instead, it uses a strong magnetic field and radio waves to create detailed images of the inside of the body.

MRI is commonly used when your healthcare provider needs detailed images of soft tissues, joints, the brain, spine, abdomen, pelvis, or other areas. Your specific MRI exam will depend on what your referring provider has requested on your requisition.

What You Need to Know

• MRI does not use ionizing radiation.
• MRI uses a strong magnetic field and radio waves to produce images.
• Routine MRI scans are not expected to cause side effects after the scan.
• A valid requisition is required for imaging appointments.
• MRI safety screening is important because the magnet can affect certain implants, medical devices, or metal objects.
• Preparation instructions may vary depending on the body area being scanned and whether contrast is involved.

Before You Book

Before booking an MRI, make sure you have a valid requisition from a licensed physician or authorized healthcare provider.

When booking, be ready to confirm:

• The type of MRI requested
• The body part being scanned
• Whether your requisition mentions contrast
• Any implants, devices, metal fragments, or prior surgeries
• Any history of claustrophobia or difficulty lying still
• Any pregnancy or breastfeeding questions, if applicable

How to Prepare 

MRI preparation can vary depending on the exam. Follow the instructions provided when your appointment is booked.

In general : Patient Prep (MRI)

• Tell the clinic about any implants, pacemakers, surgical clips, metal fragments, or medical devices.
• Remove metal items before the scan, including jewelry, watches, hairpins, hearing aids, removable dental work, and clothing with metal fasteners if instructed.
• Wear comfortable clothing if allowed, or change into a gown if requested.
• Arrive with enough time for safety screening and check-in.
• Take regular medications unless you are specifically told otherwise.

Safety Notes

MRI is considered different from imaging tests that use radiation because MRI does not use ionizing radiation.

The main safety concern is the strong magnet. Some implants, devices, or metal fragments may not be safe in the MRI environment. Always tell staff before your scan if you have or may have:

• A pacemaker or implanted cardiac device
• Aneurysm clips
• Cochlear implants
• Neurostimulators
• Surgical clips, pins, plates, screws, or joint replacements
• Metal fragments in the eyes or body
• Any implanted pump or medical device
• Prior surgery involving implanted materials

Do not guess about MRI safety. Staff can help confirm whether your scan can proceed safely.

When to Contact GNMI

Contact GNMI before your appointment if:

• You have implants, medical devices, or metal in your body
• You are unsure whether MRI is safe for you
• Your requisition mentions contrast and you have questions
• You are pregnant, may be pregnant, or are breastfeeding
• You have claustrophobia or anxiety about the scan
• You cannot lie still or flat for the exam
• You need accessibility support
• You are unsure how to prepare for your specific MRI