MRI (Magnetic Resonance Imaging)

Magnetic resonance imaging (MRI) is a diagnostic imaging technology used to detect problems in both bone and soft tissues. MRI depicts soft tissue injury and abnormalities with greater sensitivity and specificity than conventional imaging techniques. Hospital for Special Surgery has expertise in high-resolution MRI, demonstrating fine detail of articular cartilage, tendon pathology, peripheral nerve imaging, and other soft tissue structures, which are not always demonstrated on routine MRI exams.

Frequently asked questions about MRI exams

• Why has my doctor ordered an MRI exam?
• Who performs and interprets an MRI exam?
• What is special about the MR examination at HSS?
• How is an MRI performed?
• What should I do to prepare for an MRI exam?
• What are the risks?
• What are the alternatives?
• What can I expect after the MR examination?
• What happens with the results?
• Will other tests be ordered?
• MRI of Implants? Yes, we can.

Why has my doctor ordered an MRI exam?

Most people want to know why they are having symptoms of a physical problem. Your doctor has ordered an MRI to make, confirm, or exclude a diagnosis with treatment of your condition as the goal.

Who performs and interprets the MRI exam?

Your exam will be performed by a technologist who has years of training in specialized magnetic resonance imaging, under the direction of an attending radiologist. The attending musculoskeletal radiologist, who specializes in and has advanced training in orthopedic MRI, will protocol the examination of the bones and soft tissues in the area of interest and interpret your examination.

A radiologist is a doctor specializing in all imaging modalities including MRI, ultrasound, nuclear medicine, and CT. Radiologists specialize in the imaging and diagnosis of disease. Interpretation of a radiograph MRI, CT, ultrasound, or nuclear medicine examination requires expertise in pattern recognition and in the identification of potential artifacts that may otherwise be mistaken for pathology. Radiologists are trained in the variable sensitivity and specificity of each imaging technique, and in the potential for hazards related to the examination that could cause harm and must be avoided.

All the radiologists at Hospital for Special Surgery are board certified. Having years of experience in the imaging of musculoskeletal disorders, and the majority have additional formal fellowship training beyond residency in musculoskeletal or body imaging.

What is special about the MRI examination at HSS?

• At HSS, the radiologist interpreting your examination has expertise on all aspects of soft tissue and bone imaging
• Dedicated coils are used for specific body parts to obtain the best images
• MRI at HSS is performed utilizing high matrix imaging/thin sliced imaging
• Examinations of joints are performed without intra-articular injections. They are highly diagnostic, non-invasive scans.
• Techniques used at HSS have been validated for accuracy and published in peer-reviewed literature
• Customized orthopedic protocols have been developed specific to each referring physician's specialized surgical needs
• Specialized scanning performed for detailed diagnostic examinations despite orthopaedic hardware and total joints
• Highly skilled technologists perform the prescribed scans
• The Division of MRI is a GE Luminary site for testing coils and protocols for optimal musculoskeletal imaging

How is an MRI performed?

There is little or no risk in having an MRI exam. You will lie on a table within a high strength external magnet. During the examination, you will hear loud banging which is electrical gradients that drive the machine.

What should I do to prepare for an MRI exam?

Persons with severe claustrophobia may consider taking a sedative with their doctor's approval. If you are a pregnant women in the first trimester, an MRI examination is not recommended. After that, you should obtain the approval of your obstetrician.

Preparing for an MRI exam is easy. Unless your doctor tells you otherwise, you may take your medications as usual. There are no food or drink restrictions either. The only unusual preparation for an MRI scan is that all removable metallic objects must be left outside the scanning room. These include:

• Jewelry
• Keys
• Watches
• Coins
• Eyeglasses
• Hearing aids
• Dentures and other prosthetic devices

Credit cards should not be brought anywhere near the MRI magnet. Since they are magnetically coded, the MRI’s magnet, which is very powerful, can easily corrupt the information stored on them. You will be asked to change into a hospital gown.

What are the risks?

MRI is one of the safest diagnostic exams available. Unlike X-rays and computerized tomography (CT), MRI does not use radiation. However, if you wear a pacemaker or have certain body (e.g. some ear) implants, you should not have an MRI examination. You will fill out a questionnaire prior to the MRI to ensure your absolute safety.

What are the alternatives?

Alternative tests include CT (a specialized cross sectional X-ray imaging modality) and ultrasound (a non-invasive examination which uses sound instead of ionizing radiation to evaluate soft tissues).

What can I expect after the MRI examination?

There are no after effects of an MRI examination. Following an MRI examination, you will immediately be able to resume your pre-examination activities.

What happens with the results?

The radiologist will generate a written report, which will be available to your physician within 24-48 hours of the MRI exam. If your physician is at HSS, the images will be available immediately following the exam. The resulting report is sent to your referring physician and will become part of the permanent record. Your physician will review the MRI test results with you and can integrate the results of your MRI test with the findings on your physical examination and laboratory tests.

Copies of the report can be obtained through your referring physician's office. Your physician can call the file room at 212.606.1135 and a copy of the report can be faxed or mailed, free of charge, to their office. The images are the property of the institution, as are biopsy slides or blood samples. Copies of the images can be obtained on a CD by contacting the file room. There is a charge for obtaining CDs and mailing them to your physician.

Will other tests be ordered?

Additional tests to assess your problem may be ordered before of after the MRI at the discretion of your doctor.

MRI of Implants? Yes, we can.

MRI is a highly safe and accurate way to assess for the cause of a painful arthroplasty, including tendonitis, muscle tears, implant loosening and adverse tissue reactions. The MRI division at HSS is highly published in this area and continues to collaborate with scientists to develop new techniques that overcome the artifacts imposed by imaging around metallic implants, which greatly enhances the quality of imaging, enabling more accurate diagnoses.

Musculoskeletal Magnetic Resonance Imaging Center

Hospital for Special Surgery operates the largest academic orthopedic-dedicated MRI facility in the world. The Center features ten MRI units of different field strengths, enabling HSS to meet the diagnostic needs of a greater number of patients with a wider variety of conditions. The Center also offers two ultra-wide short bore unit, benefiting patients of all sizes, as well as those patients with a history of severe claustrophobia.