Medical College of Wisconsin MRI Safety Glossary

Terms and Definitions

A glossary of terms used in the research setting and MRI Safety Standard Operating Procedures (SOPs) .
Accidents, Injuries and Incidents are unexpected events or occurrences that may involve harm to a research subject, study personnel, or employees.
Accompanying Parents, Spouses, or Others
Accompanying parents, spouses, or others are individuals who, after thorough safety screening would be allowed to enter the magnetic environment to provide company and or comfort for the research subject.
Conditions are specifications determined by the manufacturer for the implant or device that allow safe MR scanning which include:
a. Static Magnetic Field (Tesla)
b. Spatial Gradient Field (gauss/cm)
c. Maximum MR system reported, whole body averaged specific absorption rate (SAR) of 2-W/kg for 15 minutes of MR scanning in a static magnetic field strength of __) (model__) MR system manufacturer)(software version___)
Equipment indicates machines that may be used for MRI studies to monitor physiological processes or provide the stimulus or physical task for the study.
Equipment Damage or Failure
Equipment Damage or Failure indicate events or occurrences that may involve harm to equipment, inside or outside of the MR scanner room, which result in the malfunction of equipment from normal operation.
Facility Safety Breach
Facility safety breach is a failed access point potentially allowing non-trained or non-escorted individuals into the magnetic environment.
Magnetic Environment
Magnetic Environment is the area where the magnetic field is greater than 5 gauss resulting in the potential for objects to become missiles or projectiles as they are attracted into the magnetic field of the scanner. Individuals who may have cardiac pacemakers or other implants and devices may be at risk to enter the magnetic environment. The magnetic field is always present and is three dimensional around the scanner.
Magnetic Resonance Imaging (MRI)
Magnetic Resonance Imaging (MRI) uses a strong static or main magnetic field, radio frequency pulses and time varying magnetic fields or gradients to produce anatomic images, spectroscopy, angiography, and functional data (fMRI).
MRI Safety Training
MRI Safety Training is the required procedure that must be completed prior to working within the magnetic environment.

Materials are pads, cushions or other objects that are not mechanical in nature but are used with or near the research subject during the MRI procedure.
Other Potential Safety Breaches
Other potential safety breaches include flooding, electrical hazards and obvious structural faults.

Principal Investigator
Principal Investigator or PI is the individual who is ultimately responsible for the procedures, study team personnel and research subjects involved in the study. The PI has an IRB or IACUC approved protocol and utilizes one or more of the MRI scanners at the Medical College of Wisconsin for research purposes.

Research MRI Scanner Operator

Research MRI scanner operator is an individual who is an employee of the Medical College of Wisconsin, has completed the MRI safety training and is specially trained in the operation of one or more of the MRI scanners. There are two levels of scanner operators:

  • Individuals who are allowed to operate the scanner for phantom and / or animal studies
  • Individuals who are allowed to operate the scanner for human research subjects studies

Individuals who are allowed to operate the scanner for human research participant studies must have current documentation as to valid Red Cross or equivalent basic life support cardiopulmonary resuscitation (CPR) training.

Research Study Personnel
Research Study Personnel are individuals including a student, staff member or laboratory assistant for whom the PI of the study is responsible, and who are at the MR scanner site during the study or may be recruiting subjects for the study.

Research Subject
A Research Subject is a human or animal participant who is placed into the bore of the MRI scanner for research purposes.

Safety Screening
Safety Screening is the process of inquiring about the safety of individuals, including research subjects prior to entering the magnetic environment. Safety screening also applies to checking equipment for safety prior to being used in the magnet room.

Spatial Gradient Field
Spatial Gradient Field is the variations (gradients) over distance (space) in the main static magnetic field from isocenter, the center of the magnetic field, within concentric rings usually stated as gauss per centimeter.

Tesla (T) is the unit of measurement for magnetic field strength. 1 Tesla equals 10,000 gauss.