What is an MRI Exam (Magnetic Resonance Imaging)?

Magnetic Resonance Imaging (MRI) is a noninvasive imaging procedure that produces detailed images without the use of X-rays or ionizing radiation. Instead, MRI captures internal images of the body’s structures and organs utilizing powerful and rapidly changing magnetic fields and radio wave pulses.

MRI produces a series of cross-sectional pictures that often provide different information about areas of the body than those images captured by X-ray, ultrasound, or a Computed Tomography (CT) scan. An MRI exam helps physicians detect and identify certain health conditions of their patients in earlier stages to provide the best opportunity for targeted treatment and recovery.

MRI provides good contrast between the different soft tissues of the body, which makes it especially useful in imaging the brain, muscles, the heart, and cancers.  Areas of the body that may undergo an MRI scan include the head, chest, abdomen, vital organs, joints, spine or extremities such as hands, wrists, ankles, and feet.

MRI is commonly used to examine:

  • Soft tissues and muscles
  • Tendons and ligaments
  • Organs of the chest and abdomen
  • The heart, aorta, arteries and blood vessels
  • The spine for disc herniations and spinal stenosis
  • Shoulder, hip, knee, wrist, and ankle joints
  • Abdomen and pelvic regions
  • Breasts and reproductive systems
  • Potential cancers or tumors and more…

MRI and radiation safety

MRI does not use ionizing radiation like X-rays. Instead, they use a very strong magnetic field and radio frequencies to produce images. The powerful magnet of an MRI machine will attract iron-containing objects that can be dangerously moved with sudden force, causing serious or even lethal injury.

You’ll be asked to remove all metallic items before entering the MRI trailer environment. To verify there are no health hazards or metal objects that could create a safety or imaging issue during your test, your HDI Technologist will have you complete an MRI safety questionnaire and carefully screen you prior to your exam.

All metallic items must be removed before your MRI including:

  • Watches, jewelry and body piercing jewelry
  • Hair accessories including hair pins and barrettes
  • Makeup or nail polish containing metal particles
  • Hearing aids, dentures, partial plates
  • Keys, beepers, cell phones and mobile devices
  • Safety pins, paperclips, picket knives and nail clippers
  • Money clips, credit or bank cards with magnetic strips or chips
  • Articles of clothing with metallic tags, threads, rivets, zippers or fasteners

There are objects that may interfere with the MRI image quality that may make you unable to receive an MRI, depending on the area being imaged.

Notify your HDI Technologist and doctor if you have the following:

  • Any kind of metallic implant anywhere in your body

  • Plates, pins, screws, or metal mesh used for bone or joint repair
  • Replacement joints or prosthesis
  • Tattoos or tattooed eyeliner (may alter images and cause skin irritation)
  • Bullet, shrapnel, or other metal fragments in the body
  • Metallic foreign bodies within or near your eye (common in metal workers)
  • Dental fillings, orthodontic braces or retainers

MRI scans cannot be performed on people with cardiac pacemakers, brain aneurysm clips, neurostimulators or metal inner ear prosthetics.

Women should always inform their physician and HDI Technologist prior to an MRI exam if they suspect they might be pregnant.


Continue taking your current medications as normal unless specified by your physician.

Food and drink

For most X-ray exams there are no restrictions on what you may eat or drink. Your physician will notify you of any exceptions.

When to arrive

Please arrive at High Desert Imaging 15-20 minutes before your exam appointment.

What to wear

Wear comfortable clothing, like sweats. Be sure to avoid clothing containing metal found in eyelets, rivets, zippers or buttons. Also be conscious of metal in any undergarments worn as it can interfere with the quality of the imaging. You may be asked to remove jewelry, eyeglasses, hearing aids or any dentures and any metal objects or clothing if necessary and gowns are available if needed.

Contrast agent

Depending on the body part being scanned, you may be given a contrast medium. This dye may be given orally as a drink, through an intravenous (IV) line, or through injection. The contrast travels through your bloodstream and helps create a clearer picture of specific parts of your body. Contrast agents highlight your organs and blood vessels for better interpretation of images. If your exam requires oral contrast, you must pick up the contrast from HDI at least one day prior to your exam.

Please notify your doctor and HDI Technologist if you have ever had an allergic reaction to a contrast material administered for a medical imaging procedure. Contrast materials used today contain a lower iodine content that greatly reduces the chance of an allergic reaction and most of the discomfort associated with injection.

You may have a higher risk for a complication due to a contrast if you:

  • Are over 60 years of age
  • Had a previous allergic reaction to contrast dye
  • Have a serious heart condition or disease
  • Have diabetes or lupus
  • Have severe kidney disease, especially if due to diabetes
  • Are receiving dialysis
  • Have severe allergies to any drugs or foods
  • Have unstable asthma that requires treatment
  • Have sickle cell disease, polysythemia, or multiple myeloma

If you have any of the conditions above, speak with your doctor and HDI Technologist. You may need a blood test beforehand to make sure the contrast will be safe for you.


If you have a pacemaker, under no circumstances should you undergo an MRI exam.


Some patients who undergo MRI examinations might feel confined, closed-in, or frightened while undergoing their exam. HDI Technologists want you to be as comfortable as possible during your exam and may offer to play some music for you (you may bring your own CD), or apply a cloth over your eyes, if desired. If you have a concerning case of claustrophobia, you can ask your doctor to prescribe a sedative for you to take the day of your exam but you’ll need to arrange for a friend or family member to drive you home afterward.

The MRI environment

High Desert Imaging’s MRI system environment is located in a 48’ x 8.5’ mobile trailer connected to our facility and accessible from inside our office by ascending a small set of stairs or using a hydraulic lift leading into the trailer. The MRI trailer environment has a dressing room where you can change and securely leave any belongings during your exam, an imaging computer station where your HDI Technologist and Radiology Physician can record and review scanned images, and the main exam area containing the MRI machine.


An MRI examination is painless but you will be required to remain as still as possible during the scanning procedure. Your HDI Technologist will position you on the table in a comfortable position to make it easy for you to remain still and relaxed during the exam as movement can blur the images. If you are feeling claustrophobic and are not on a sedative prescribed by your doctor, your HDI Technologist can offer a few options to help calm you; see the Claustrophobia details in the Exam Preparation tab on this page.


The MRI scanner consists of a long motorized bed that moves inside a large cylindrical tunnel to surround the body part being scanned by the cylindrical magnet. When you’re lying on the MRI bed positioned inside the imaging tunnel during the exam, the scanner does not touch you and you will not feel anything. Because the scanner does make loud knocking noises of various pitches when it takes the pictures, we will offer earplugs to lessen the sound or headphones to listen to music we provide or you may bring your own on a CD.

During your exam, your HDI Technologist will be in the next room over and he or she will have you in full view and communicate with you using an intercom inside the MRI. It is important for you to lie very still during the procedure, and at some points you may be instructed to briefly hold your breath as an image is taken.

Length of scan

MRI exams can last between 15 and 90 minutes depending on the size of the area being scanned and the number of images required. Ask your HDI Technologist how long your exam is estimated to take.

After your MRI

If you are a woman who is breast-feeding at the time of your scheduled MRI and received a contrast agent, it typically take 24-hours for a contrast agent to be cleared from your body.

After your exam, you may resume your normal activities, diet, and medications unless instructed otherwise by your HDI Technologist or doctor. If you received a contrast medium before your exam, call your doctor if you experience pain, swelling or redness at the injection site or have an allergic reaction to any contrast administered. Be sure to drink plenty of fluids to help eliminate the contrast medium from your body.

Scan results 

We pride ourselves on delivering superior studies and rapid exam results. Diagnostic exams are typically read within 24 hours with results sent to your primary care physician who will go over them with you in detail. We’ll also provide you with a DVD copy of your exam images.

If you have additional questions about HDI’s MRI procedures, please use our online contact form or call us at 775.621.5800.