An MRI scan uses a powerful magnetic field to align the magnetization of some atoms in the body, and radio frequency fields to systematically alter the alignment of this magnetization. This causes the nuclei to produce a rotating magnetic field detectable by the scanner—and this information is recorded to construct an MRI image of the scanned area of the body. Strong magnetic field gradients cause nuclei at different locations to rotate at different speeds. 3-D spatial information can be obtained by providing gradients in each direction.
MRI services performed by our expert staff include:
- MRA (MR Angiography)
- Breast MRI
- Cardiac MRI
What is Magnetic Resonance Imaging (MRI)?
MRI uses a large magnet, radio waves, and a computer to view soft tissue hidden from view by bone.
Why is this exam done?
Scans of the brain, head and neck, spine, abdomen and pelvis, and musculoskeletal system allow the radiologist to detect injuries and abnormalities, diagnose numerous conditions, and monitor the success of treatment. With MRI scans, it may be possible to identify and, therefore, treat conditions in their early stages.
What will happen during the exam?
The technologist will position you on the scanning table, and offer you pillows and blankets to make you feel comfortable and relaxed. The technologist may also place a surface coil around the part of the body to be scanned.
The nurse or physician may give you an intravenous injection halfway through the exam if a contrast agent is needed to enhance the images. While you lie flat on a table, it will be moved into the opening of the MRI system.
During the exam, you must remain still. The technologist, now in an adjoining room capturing the images on a computer screen, can talk to you throughout the exam. If you experience any unpleasant feelings, just alert the technologist. Remember, the technologist can see and hear you at all times.
If the noises associated with the MRI system make you uncomfortable, headphones playing a favorite tape or CD and earplugs are available. You will find the exam to be painless and safe.
The entire procedure takes from 1/2 to 1 hour, depending on the test.
What are the risks and benefits?
Because certain conditions interfere with MRI scans, be sure to alert your RGHS care team if you have any of the following: pacemaker, surgical brain clip, vena cava filter, metallic foreign body in the eye, metallic heart valve, neurostimulator, neurosurgical aneurysm clip, ear implant, eye implant (other than cataract) or stent. In addition, alert your physician and your RGHS care team if you may be pregnant or have specific questions or concerns.
How should I prepare for my test?
When you go for your appointment, consider wearing a sweatshirt and sweatpants or other clothing that does not have zippers or metal fasteners, since these interfere with MRI scans. Also, please plan to arrive and check in with the receptionist 15 minutes before your appointment is scheduled.
RGHS has two MRI systems. Although both systems are designed for patient comfort, any scan can cause some anxiety, so be sure to let your physician and your RGHS care team know if you think you may be claustrophobic. The physician may want to prescribe a sedative, and the exam will likely be scheduled on the MRI system with the wider patient opening. You will have the option of listening to a tape or CD during the exam, so feel free to bring a favorite recording along, or make your selection from a variety available at RGHS.
Any special instructions for after my test?
If no additional radiological tests are scheduled, you will be able to dress and leave the facility. You can resume your usual activity. There should be no side effects.
Once the technologist prepares your images, the radiologist will read the images and dictate a report that will be sent to your referring physician within 2-3 days. If the actual MRI images are needed, please allow 1-2 days notice.
Is this test compatible with pacemakers?
New pacemakers and defibrillators have been developed that have conditional approvals to be used during magnetic resonance imaging (MRI). Several Medtronic pacemakers, the Advisa DR MRI and Revo MRI SureScan, received FDA approval to be MRI conditional without any limitations on the positioning of the patient or parts of the body safe to scan. FDA approval is based on review of both clinical data as well as computer modeled simulations of chest scans. These pacing systems are designed to allow patients to undergo MRI under specified conditions of use. Rochester Regional Health MRI sites have been registered with Medtronic and MRI personnel have completed Radiology SureScan training.