Patient Safety Topics
Magnetic Resonance

​​​A magnetic resonance imaging (MRI) scanner has strong forces that can move an internal ferromagnetic object (made of or having parts made of substances such as iron, nickel, and cobalt), which can be magnetized by exposure to a magnetic field. Further, the scanner can erase the memory or impair the function of a medical device and turn a ferromagnetic object into a projectile that can injure or kill. Because of this magnetic field and the associated radiofrequency energy, providing MRI screening for patients and staff is critical to their individual safety. Screening ensures that no ferromagnetic objects or objects (in or on anyone) that conduct electricity enter the MR scanning area.

Key Data and Statistics

​Analysts queried the Pennsylvania Patient Safety Reporting System database for MRI screening events submitted from January 1, 2009, through December 31, 2017. Of the identified 1,108 MRI screening events, the reports range from uncompleted MRI screening forms to ferromagnetic projectile events causing patient injury. Additional factors evident from analysis included the following (see also Figure 1):

  • Five events were designated as Serious Events:
    • One was related to a nonmedical object projectile
    • One led to a thermal injury from an external medical device
    • Three led to malfunction or displacement of an internal medical device
  • The number of reports has trended downward over the past 9 years.
  • Of the MRI screening events with identifiable objects or devices, 64.8% (n = 708 of 1,093) involved internal medical devices and nonmedical objects; the most frequently involved items were pacemakers (32.3%, n = 353 of 1,093).
  • More than one-third (35.2%; n = 385 of 1,093) of events involved external objects, carried in by or attached to the patient or healthcare staff.

Figure 1. 

Excerpted from: Field C. MRI screening: what’s in your pocket? Pa Patient Saf Advis 2018 Dec [cited 2018 Dec 19].

Educational Tools

Magnetic Resonance Imaging Patient Screening Form
Magnetic resonance (MR) facilities and units can refer to this sample screening form as a guide in developing facility-specific forms.


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