What is a MRI Scan?

MRI scan taken at torrance memorial imaging center

MRI stands for Magnetic Resonance Imaging. MRI uses a strong magnetic field and radio waves to produce high-resolution images of the brain, spine, joints, internal organs and other parts of the body. MRI helps radiologists in making an accurate diagnosis as well as assessing treatment already in progress. At Torrance Memorial Medical Center we have invested in some of the most technologically-advanced and powerful MRI scanners available today.

Pre-Screening Before Your MRI

Because of the strong magnetic field used by MRI, patients must fill out a screening form before having an MRI exam. The screening is to identify potential risks that may make MRI unsafe or may interfere with image quality. Patients who have implanted medical devices, including heart pacemakers or defibrillators, brain aneurysm clips or cochlear implants may not be eligible for MRI.


If you are uncomfortable in an enclosed space, you'll be glad to know that Torrance Memorial Medical Center provides the option of having your MRI exam done on one of our Large Bore MRI Scanners. This type of MRI scanner is more comfortable for patients with claustrophobia because it is shorter and has a larger opening. For these reasons open MRI can also be a good option for people who are overweight, obese or otherwise larger than usual. If you prefer this, please let the scheduling department know so they can accommodate you.

Preparing for Your MRI

For most MRI scans you may eat and drink as usual.

Sometimes, however, you may receive special instructions. Some MRI scans require that you fast for up to eight hours prior to your appointment. (If you need to take medications, you may do so with a small amount of water – ask your doctor for specific advice.) Some patients need to drink an oral contrast agent in preparation for their MRI.

How Long Will the Exam Take?

The length of time an MRI takes depends on the area of the body being studied. Generally speaking, most MRI scans take between 20 minutes and one hour.

Multiple pictures are usually needed to complete an MRI exam. Each set of pictures can take anywhere from a few seconds to fifteen minutes. Our staff will do their best to complete your exam successfully and efficiently with minimal stress. You can help ensure your scan is completed quickly by remaining as still as possible, especially when you hear the scanner taking the images.

Typical exam times are as follow:

Routine Brain 10-15 minutes
Brain with Contrast 15-30 minutes
Cervical Spine 15-20 minutes
Thoracic Spine 15-20 minutes
Lumbar Spine 15-20 minutes
Shoulder 15-20 minutes
Hip 15-20 minutes
Knee 15-20 minutes

What Happens During an MRI Scan?

mri siemens avanto

For certain MRI exams, a contrast agent ("dye") will be injected into a vein to highlight certain organs or tissues in your body. This is typically done in the middle of the exam.

The MRI scanner is a large "donut-shaped" machine that is open on both ends. You will be asked to lie on the table. Depending on the exam you need, your MRI technician may instruct you to stay in a particular position. The table will slide into the machine until the part of your body to be imaged is in the center.

MRI equipment makes loud "knocking" noises while taking pictures, due to the magnetic fields used to generate the images. Earplugs or headphones will be provided for your protection and comfort. Music may also be available upon request.

It is important to be very still during the scan, as movement creates blurry images. Although you will be alone in the MRI scanner, you will be able to communicate with the MRI technologist through a special speaker inside the machine.

After Your MRI

Most patients having MRI scans on an outpatient basis are able to resume all regular daily routines and activities immediately afterward. If you took medication to relax during the scan, you'll need to have an adult accompany you home. If you were given IV contrast, you'll need to drink extra fluids afterwards to flush it out of your body.

How Will You Learn About Your Results?

The technologist will not give you the test results directly, as the images still need to be reviewed by a radiologist. After reviewing the study, the radiologist will send an official report to your physician, who can then discuss the results with you.

For More Information

For more information on these types of exams please visit www.radiologyinfo.org.

Schedule an Appointment

We make it easy to schedule an imaging appointment.