Updates on the MR safety guidelines – Essentials for radiologists

Abstract

Magnetic Resonance Imaging (MRI) is a sophisticated diagnostic tool that utilizes the magnetic properties of biological tissue to generate detailed images of internal structures without the use of ionizing radiation. Despite its benefits in providing high-contrast images of soft tissues, the strong magnetic fields used in MRI present a unique safety challenge. Increasing MRI-related accidents and the prevalence of patients with metallic implants in recent years underscore the critical need for stringent MR safety protocols. This article reviews the latest 2024 updates in the MRI safety manual by the American College of Radiology (ACR), highlighting the comprehensive efforts to manage risks associated with MRI, including projectile and burn incidents, patients with medical devices, and emerging complex MRI environments. The manual emphasizes the importance of specialized training for healthcare professionals to navigate the complexities of MRI safety to ensure patient and staff safety. This review also touches on the dynamic landscape of MRI safety standards, driven by technological advances and evolving clinical practices, aiming to provide a thorough understanding of current best practices in MRI safety management.

List of updates

• 1.
  Reformatted introduction: Provides a basic overview of MR risks and safety concerns, setting the stage for comprehensive safety protocols.
• 2.
  Management of MR Safety and Policies: Updates guidelines for creating, implementing, and maintaining MR safety policies, emphasizing new considerations for policy development.
• 3.
  MR Environment: Updates the fringe field limit to 9 gauss, reflecting the latest safety standards by the International Electrotechnical Commission (IEC).
• 4.
  MR Personnel: Enhances MR Safety Training with updated language, introduces a training checklist, provides new staffing guidance, and incorporates remote scanning protocols.
• 5.
  MR Screening: Reorganizes and clarifies the process for screening staff, patients, and materials for MR safety, including risk identification and the use of MR Safe attire.
• 6.
  Final Stop/Final Check: Introduces routine and augmented protocols, including the mandatory removal of hearing aids before entering Zone IV.
• 7.
  Zone IV Exam Preparation and Completion: A new section that outlines specific procedures for preparing and completing exams in the high-risk Zone IV area.
• 8.
  MRI Fields and Safety Concerns: Reorganizes critical information on RF Magnetic Fields and Magnetic Field Gradient concerns, addressing whole-body, focal, and resonant heating, as well as auditory impacts and nerve stimulation.
• 9.
  Classification of Objects and Medical Devices: Updates classifications for MR safety labeling, ensuring clarity in identifying safe, conditional, and unsafe items in the MR environment.
• 10.
  Introducing Portable Metallic Objects and Equipment: Separates guidance on portable metallic objects and equipment, focusing on labeling, testing, and temporary provisions for unsafe transport equipment.
• 11.
  Managing Patients/Subjects with Medical Devices: Establishes a new section for managing active and passive implanted devices, including procedures for unexpected discoveries during MR exams.
• 12.
  Emergency Situations: Introduces protocols for handling emergencies, including equipment shutdowns, quenches, fires, and patient entrapment, ensuring rapid response and safety.
• 13.
  Special Patient and Personnel Considerations: Updates considerations for special patient populations, including new guidance for high BMI patients, and protocols for managing anxiety, claustrophobia, and sedation.
• 14.
  Alternative MR Environments: Explores the use of MR technology in alternative settings such as PET/MR, intraoperative MR, and mobile units, addressing new technologies and their safety protocols.
• 15.
  Appendix 1: Provides comprehensive guidance on MR Safety Policies and Standard Operating Procedures, serving as a reference for best practices
• 16.
  Appendix 5: Offers a new risk/safety assessment framework for implanted devices, aiding in the pre-examination evaluation process