Background
MRI has become a vital diagnostic tool for evaluation of nearly all structures and organs within the human body. MRI has become the gold standard for imaging in certain pathologies and favored imaging modality, especially without the risk of radiation. There is increasing reliance on MRI, resulting in scrutinizing safety policies and screening guidelines. As a result, MR safety has become an important factor before a patient is able to be imaged.
Educational Goals / Teaching Points
In our educational exhibit, we plan on describing the three major components of an MRI system as they relate to safety guidelines and their associated key risk factors. We list classification of various objects and devices within the MR environment. We describe the MR safety zones and the associated restrictions. We describe different emergencies and their management pertaining to MR Safety Zone IV. We discuss newer concepts and terminology.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
We will discuss the features of main magnet, gradient systems, and radiofrequency coils (the three major components of MRI system hardware, in accordance with MRI safety guidelines), and the key risk factors related to the hardware. Standard MRI safety terminology for devices including examples of MR safe, MR conditional, and MR unsafe devices will be illustrated. The division of MRI environment into four safety zones, progressive restriction of entry, and increased supervision for higher zones, and the key role of these safety zones in the avoidance of MRI-related accidents will be discussed. The emergencies in zone IV (i.e., cardiac arrest or code, fire, magnet quench, and entrapment) and their management will be described. The conditions in which a quench should be initiated and the emergency quench procedure will also be discussed. Emphasis will be placed on newer concepts and terminology in MRI safety, which include full stop and final check processes in zone lll to ensure appropriate screening of patients in routine and augmented settings, as well as examples of alternative MR environments and required safety policies and procedures in such facilities. We will also discuss safety precautions for scanning patients with metallic foreign bodies. According to the U.S. FDA, burn injuries are most common and account for 59% of MRI-related adverse events. Other less common safety events include mechanical injuries and metal objects turning into projectiles, which can result in serious injury and even death. Documented examples of MRI mishaps will be illustrated. We will discuss the causes of MRI adverse events and safety measures to avoid them. As the list of items that could pose MRI safety risk increases, it is important to keep track and continuously update the list.
Conclusion
MRI safety has become an important and vital component of the referring provider, patients, staff, and radiologist involved with improvement of safety guidelines and prevention of adverse events.