As your go-to radiology equipment and medical supply store, Techno-Aide utilizes MRI terminology developed in 2005 by the American Society for Testing and Materials (ASTM). In an effort to clarify the terminology this new system references the MRI environment where testing took place, which includes the location inside the static magnetic field and its magnitude, spatial gradients, time-varying magnetic fields, radio frequency (RF) magnetic field pulses and specific absorption rates (SAR).
Three categories were developed: MR Safe, MR Conditional, and MR Unsafe which characterizes the behavior of a medical device under specific conditions in the MRI environment as determined by testing. In addition to the new terms, the ASTM International document introduced corresponding icons consistent with international standards for colors and shapes of safety signs. The icons are intended for use on items that may be brought into or near the MRI environment as well as in product labeling. The new terminology and icon structure is intended to help clarify matters related to biomedical implants and devices to ensure the safe use of MRI technology.
The "MR Safe" icon consists of the letters "MR" in green in a white square with a green border.The "MR Conditional" icon consists of the letters "MR" in black inside a yellow triangle with a black border. The "MR Unsafe" icon consists of the letters "MR" in black on a white field inside a red circle with a diagonal red band.
Further details and a comprehensive discussion of the labeling applied to passive implants are presented in the FDA document, Guidance for Industry and FDA Staff - Establishing Safety and Compatibility of Passive Implants in the Magnetic Resonance (MR) Environment
MR SAFE: The product is completely nonmagnetic, nonelectrically conductive, and nonradiofrequency reactive, therefore eliminating all the primary risk during MRI scanning.
MR CONDITIONAL: The product may contain magnetic, electrically conductive, or radiofrequency-reactive components that are safe for operation in proximity to the MRI, provided the conditions for safe operation are defined and observed (both for the MR scanner and the product itself) Tested in environments up to 7Tesla or less.
MR UNSAFE: Product is significantly ferromagnetic and will pose a clear and direct threat to persons and equipment within the MRI room. NOT approved inside the MRI suite.