MRI Equipment Safety

Magnetic resonance imaging, or MRI, can cause potential hazards if the proper safety procedures are not used. Screening patients for metal objects, knowledge of patient medical history and in-depth training for employees are key preventative measures. Certain precautions must also be taken with women who may be pregnant.

Definition and Purpose

• An MRI provides a view of your body's internal organs through the use of radio waves and a strong magnetic field. When you are in the unit, the magnetic field brings the molecules of water inside your body into alignment. The emitted radio waves cause your molecules to give off a signal that the machine can turn into an image. The pictures are taken in sections and then are combined into an overall, three-dimensional image.

Initial Screening

• A pen can become an airborne projectile if allowed near an MRI.

  Before the MRI is done, anyone entering the room containing the MRI equipment has to be carefully checked to make sure that he has no metallic objects on himself. The magnet's field is extremely strong, and any small metallic items can become flying hazards. These include watches, pens, pencils, jewelry, credit cards and keys. The patient and any staff entering the room must leave these items behind. The patient's medical history must be thoroughly reviewed for any metallic devices, including implants, plates and screws, which have been surgically put into an individual's body.

Noise Level

• Protect the patient's hearing by providing her with ear plugs.

  As the machine takes images of the patient, it can create high-decibel noises, which can cause temporary or permanent hearing loss. Protect the patient's hearing by supplying her with a pair of ear plugs before the procedure. Noise-reducing headphones can also be used if they are deemed safe for the MRI.

Patients Who Are or May Be Pregnant

• When patients need an MRI, they are often injected with a substance called Gadolinium. This helps to improve the picture quality that the machine takes of the organs. It is not recommended for use on a pregnant woman unless it is absolutely necessary. A small potential for hearing damage in the fetus also exists due to the loud noises emitted from the machine. An MRI should only be done only if required, and the mother should give written consent before undergoing the procedure. If a patient thinks that she may be pregnant, a pregnancy test should be done before scheduling an MRI.

Implants

• In addition to external metallic objects, other units surgically placed within the body can be a danger in the MRI. The magnetic field can cause the device to move out of place. Burns can be sustained if the magnet causes an electrical current in the device's wiring. Other devices such as cochlear implants, pacemakers and defibrillators are not to be allowed near an MRI; the magnetic field can alter a pacemaker's programming, for instance, and create a hazard for the patient. A patient with surgical implants must be cleared by a doctor before having an MRI.