Magnetic resonance imaging or MRI is a non-invasive medical imaging technique that utilizes a magnetic field, radio waves, and computer technology to create detailed images of several structures in the body, including bones, organs, tissues, and blood vessels. There is no radiation produced during this procedure.
MRI machines typically consist of large cylindrical (tube-shaped) magnets. Machines work by creating a strong magnetic field that temporarily aligns hydrogen atoms in the body in the same direction. Radio waves then cause these atoms to produce signals which are received by a computer to create an image of the part of the body being examined.
Your doctor may have requested an MRI scan to help diagnose, evaluate, or treat a variety of conditions including:
- Malformation or inflammation of the blood vessels
- Inflammation of the bowels
- Tumors
- Brain aneurysms
- Brain and spine injuries
- Stroke
- Congenital heart disease
- Liver disease
- A developing fetus
MRI scans are generally safe; however, the presence of metal in or on the body can pose a safety hazard if attracted to the machine’s powerful magnets. Certain electronic or metal devices in the body may not be certified as MRI-safe. Individuals with the following objects or medical devices in their bodies may not be allowed to get an MRI scan:
- Pacemaker
- Artificial heart valves
- Cochlear implants
- Bullets, shrapnel, or other metal fragments
- Metal clips
- Metallic joint prostheses
- Certain metal coils placed within blood vessels
- Vagal nerve stimulators
Patients with tattoos or permanent makeup are advised to speak with a doctor about their options before getting an MRI because the pigment used in darker inks may contain metal.
People who are pregnant, breastfeeding, claustrophobic, or diagnosed with kidney or liver problems are also advised to speak with their doctor to explore the risks of getting an MRI and options for testing.
How To Prepare For An MRI
Your doctor will provide guidelines before an exam. Most patients are informed to continue taking their medications unless instructed otherwise. Instructions on eating and drinking will vary between certain examinations.
A radiologist or radiology technologist will perform your MRI. Before the examination, you may be asked to remove objects that can be attracted to the magnets or interfere with imaging, such as:
- Wigs
- Magnetic eyelash extensions
- Cosmetics with metallic components
- Hairpins or other metallic hair accessories
- Watches
- Jewelry
- Body piercings
- Eyeglasses
- Hearing aids
- Dentures
- Bras with underwire
What To Expect During And After An MRI
Your technologist or radiologist will ask you to lie down or position you on a moveable exam table that slides into a tube. They may use straps or bolsters to help you stay still during the procedure. You will be provided with a call button to alert the technologist or radiologist if you’re having any problems or concerns.
If your examination includes the use of a contrast material, an intravenous (IV) line will be inserted into your arm to inject the material.
The MRI machine produces several noises such as thumping, clicking, or tapping while creating images, you may be given earplugs or the choice to listen to music to help dampen these sounds.
An MRI can last anywhere from 15 minutes to more than one hour. During the exam, your technologist or radiologist will monitor you in another room. They will speak to you through an intercom that allows two-way communication.
During the procedure, It is important to remain still unless instructed otherwise because motion can affect the quality of the images. You may also be asked to hold your breath at certain intervals, depending on the part of the body being examined.
If you are receiving a functional MRI, you might be asked to perform small tasks such as answering simple questions or lifting your arm.
You can resume normal activities immediately after your examination. No recovery period is necessary except if you have received sedative drugs during the scan. You will need to recover from the effects of drugs before you can be sent home.
Jamaica Hospital’s Radiology Department is designated as a Diagnostic Center of Excellence by the American College of Radiology (ACR). Receiving this designation means our team has met or exceeded the high standards of the ACR for providing safe and high-quality imaging care to our patients.
To schedule an appointment with our department, please call 718-206-6743.
Our hours of operation are as follows:
Monday to Friday- 7:30 am- 6 pm
Saturday and Sunday- 8 am- 4:30 pm
