Magnetic Resonance Imaging (MRI)
What is MRI?
Magnetic
Resonance Imaging (MRI) examinations have become one of the most
frequently ordered diagnostic technologies. This is because MRI uses
radio waves and a strong magnetic field to provide precise detail of
the internal organs, body tissues and associated conditions or
diseases. For example, MRI can help visualize joint and musculoskeletal
disorders as well as physical changes resulting from cancer, stroke,
and vascular/heart disease.
Other diagnostic uses of the MRI may include showing abnormalities
of the brain, hemorrhage, tumor, infection, multiple sclerosis, and
demyelinating disease. Head and neck MRIs may reveal carotid artery
disease, nasopharyngeal tumors, and sinus disease. MRI of the spine may
isolate disorders such as bulging or herniated disk, spinal stenosis,
and metastatic disease.
MRI equipment is categorized according to magnetic field strength.
Low field units are about .6 Tesla and are suitable for some brain and
spine imaging. However, the image quality is not as precise as the
higher field strength units such as the 1.5 Tesla MRI units. The 1.5
Tesla units produce the best image quality and provide superior brain
and spine imaging as well as orthopedic imaging of the joints.
MRI images themselves look like axial slices through the anatomic
structure. The MRI computer can reconstruct or "re-slice" the images at
any angle. These allow the physician team to better view and/or isolate
any areas of particular interest.
How should I prepare?
Appointments may be scheduled at our Puyallup, Sunrise and Bonney
Lake Imaging Centers as well as our hospital-based Radiology
Departments at Allenmore Hospital in Tacoma, and Good Samaritan
Hospital in Puyallup. Also consider Covington, Auburn, Kent, Northshore
and Gig Harbor MultiCare locations. For children, larger individuals or
people with claustrophobia, we offer a large, ultra-short bore, for a
more comfortable, less claustrophobic MRI option. Our Espree MRIs are
located in Puyallup, Sunrise and Bonney Lake Imaging Centers.
MRI scans are very precise, so patients may expect to spend 30-60 minutes in the MRI magnet. Occasionally,
contrast may be ordered to provide enhanced images. The contrast media
is administered intravenously, is very safe to use, and improves image
quality by enhancing our views of the vascular compartment.
Patients should wear non-metallic, comfortable, loose clothing such
as a jogging outfit and tennis shoes. There is a very strong magnetic
field, which exerts considerable force on paramagnetic or metal objects
and disturbs electronic devices placed in the field.
It is imperative that patients notify the MRI technologist in
advance if they have any metal objects on, or in, their bodies. If
patients have any of the following, they should not go into the strong
magnetic field of the MRI magnet:
- Cardiac pacemaker or Artificial heart valve
- Cerebral aneurysm metal clip in the brain
- Other surgical clips
- Insulin pump
- Cochlear implants
Additionally, please inform the MRI staff prior to your appointment if any of the following apply to you:
- In the first trimester of pregnancy
- Are a metal worker or hobbyist
- Have other metal (pins, screws, plates) or prosthetic implants (i.e. hip, knee)
- Are involved in certain types of manufacturing
- Are a victim of a car accident
Let us know if you have any tattoos, permanent eyeliner,
multiple metal tooth fillings or orthodontic braces. Also make sure to
remove any earrings or metal items from body-pierced locations.
The magnetic field will also erase the magnetic strip information on credit cards. Also,
please make arrangements to keep your children at home on the day of
your appointment. There are no childcare services onsite...and due to
the presence of radiation, children are not allowed to enter exam rooms
during imaging procedures.
What should I expect?
At the beginning of the examination, you may be asked to remove your
eyeglasses, hearing aids, and/or any non-permanent dental appliances.
You will be positioned comfortably on a sliding table near the
center of the MRI unit. The Technologist will then leave the room.
He/she can still see, hear and communicate with you throughout the
procedure.
You will be asked not to move during the actual imaging process.
During the procedure, most MRI scanners make a loud "tapping or
knocking" noise as the magnetic coils change pulse directions. You will
be given ear plugs to wear.
MRI procedures are not painful. You may feel a "warm" sensation in
the area being scanned. This is normal. If you feel uncomfortable by
the feeling, let your Technologist know. Some patients may benefit from
mild sedation prior to the scan. If needed, your physician will need to
prescribe one for you. Most often sedatives are not required.
When the exam is completed, you will be asked to wait until it is
determined whether any additional images are required. If not, you will
be allowed to redress and return home. Results are usually available
3 working days after the procedure. Please contact your referring
physician for results at that time.
Medical Imaging Northwest is accredited by the American College of Radiology (ACR) in MRI.
Which locations provide this service?
- Puyallup Imaging Center
- Sunrise Imaging Center
- Bonney Lake Imaging Center
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