The biggest and most important component in an MRI system is the magnet. The magnet is rated using a unit of measure known as a tesla. The magnets in use today in MRI are in the 0.5-tesla to 2.0-tesla range or 5,000 to 20,000 gauss. 2.0 tesla is a stronger, faster magnet, thus providing a higher quality image in a shorter amount of time than for example a 0.5 tesla magnet. Compared with the Earth's 0.5-gauss magnetic field, you can see how incredibly powerful these magnets are.

Most imaging modalities use injectable contrast, or dyes, for certain procedures. MRI is no different. What is different is the type of contrast we use, how it works, and why we use it. MRI contrast works by altering the local magnetic field in the tissue being examined. Normal and abnormal tissue will respond differently to this slight alteration, giving us differing signals. These varied signals are transferred to the images, allowing us to visualize many different types of tissue abnormalities and disease processes better than we could without the contrast.

Although there is no risk of radiation using MRI, we must take one critical precaution while in the magnet suite:  the magnet strength will attract metal objects if they are taken into the scan room.

For example, paperclips, pens, keys, scissors, hemostats, stethoscopes and any other small objects can be pulled out of pockets and off the body. Strict precautions are taken prior to allowing a patient or support staff member into the scan room; he or she must remove all metal objects and jewelry.

Patients that have implants, metallic fragments in the eye, pacemakers, aneurysm clips, and some dental implants cannot be scanned.

Most orthopaedic implants are fine because they are firmly embedded in bone. Each time we encounter patients with an implant or metallic object inside their body, we investigate thoroughly to make sure it is safe to scan them. There is usually an alternative method of imaging that we can use to help them.

Most facilities prefer not to image pregnant women.

This is due to the fact that there has not been much research done in the area of biological effects on a developing fetus. The decision of whether or not to scan a pregnant patient is made on a case-by-case basis with consultation between the MRI radiologist and the patient's obstetrician.

• Diagnosing infections in the brain, spine, or joints
• Visualizing torn ligaments in the wrist, knee, and ankle
• Visualizing shoulder injuries
• Diagnosing tendonitis
• Evaluating masses in the soft tissues of the body
• Evaluating bone tumors, cysts, and bulging or herniated discs in the spine
• Diagnosing strokes in their earliest stages
• Diagnosing multiple sclerosis (MS)
• Diagnosing tumors of the pituitary gland and brain

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Frequently Asked Questions

If I have a metal in my body, can I still have a MRI?

Patients that have implants, metallic fragments in the eye, pacemakers, aneurysm clips, and some dental implants cannot be scanned. Most orthopaedic implants are fine because they are firmly embedded in bone. ProScan will evaluate each patient prior to being scanned.

I am a large person; will I fit into the MR?

ProScan can accommodate larger patients up to 500lbs

I am claustrophobic and need a MR – what can I do?

ProScan prides itself in working with claustrophobic patients. We suggest you obtain a prescription from your doctor for a sedative. We also have OPEN MRI's at some of our centers that give patients a less-enclosed sense. Our technicians will also supply you with covers for your eyes, headphones, and upon request, you can even have a family member sit with you while you are scanned (providing they have no metal in or on their body).

What can I expect from my scan?

You will change into a gown and be situated on the MR table. The technician will explain the scan they are doing and inject contrast (if required) for the scan. The MR makes a noise that sounds like a continual, rapid hammering. You will be given earplugs or music headphones to muffle the noise. (The noise is due to the rising electrical current in the wires of the gradient magnets being opposed by the main magnetic field.)

The table will move you under the magnet and scanning will begin. MRI scans require patients to hold very still for extended periods of time. Now is your time to simply relax. In fact, many people fall a sleep while being scanned.

MRI exams can range in length from 20 minutes to 90 minutes or more. Even very slight movement of the part being scanned can cause very distorted images that will have to be repeated.

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