When used as directed, MRI represents perhaps the most advantageous tradeoff of patient risk for clinical information that has ever been made. The number of patients with injuries attributed to MRI equipment malfunction is shockingly low, particularly when you consider that roughly thirty million MRI exams are administered annually in the US (enough for MRIs for 1 out of every 10 adults)! And yet, we continue to hear of patients being injured during MRIs.
The problem - it turns out - isn’t the MRI equipment, it’s everything but the equipment.
One of the most frequent injury types is magnetic projectiles. While the total number of reported projectile injuries is less than the cumulative number of all MRI burn types, projectile accident numbers compete with each of the three main different burn types, individually, and projectile accidents represent some of the most serious injuries, from broken bones, to impalements, to death. What we may not realize is that the physical environment around the MRI contributes, directly, to both the amount of risk and the value of prevention with respect to MRI projectile injuries.
Before Henry Ford, people built complex machines. Then, the widgets were ‘over there’. The sprockets were ‘in that drawer, over there’. The gizmos were packed in the box in the closet. And the whosi-whatsits were kept in the locked cabinet. Arguably greater than the automobile was Ford’s popularization of the assembly line… developing a work space that promoted efficient and effective outcomes. This concept was further refined with the study of ergonomics (a study championed, not surprisingly, by McDonalds to promote efficiency and consistency in hamburger preparation). When it comes to our everyday work tasks, our buildings *are* the assembly lines from Ford’s era… the means by which we can help assure efficient and quality production.
When it comes to efficient and effective patient care in radiology environments, including MRI projectile safety, facility design is tremendously important. For projectile safety in the MRI suite, two principles govern: awareness and segregation.
Awareness has several components in a safely operated MRI suite. The MR technologist needs to be aware of what equipment can be used safely near the magnet. To this end, objects that reside in the MRI suite (or might regularly be brought to the suite) need to be prospectively identified and labeled with their safety properties. ‘Can this pump be used inside the MRI scanner room? If so, how close to the magnet? What are the limitations or conditions for safe use?’ For these issues, it is strongly recommended to use equipment in the MRI suite that would be safe inside the MRI scanner room. And all equipment should be conspicuously labeled with the known conditions for safe use.
The MR technologist must be aware of who is approaching the entrance to the MRI scanner room, to be able to verify that they, indeed, have been properly screened that they can safely enter the area of high magnetic field. Effective this July, this will be a requirement of Joint Commission accredited providers. At RAD-Planning, we only design new MRI suites with a direct line-of-sight from the operator’s console to the MRI scanner room entrance, but compliance with the new Joint Commission requirement could conceivably be achieved with closed-circuit video monitoring, if a facility’s layout precluded line-of-sight.
Lastly, a technologist needs to be specifically aware of materials brought to the MRI suite that are potential projectiles. The most widely used hospital building code, Guidelines for Design and Construction of Health Care Facilities, has since 2010 required the use of MRI-safety specific ferromagnetic detectors in MRI suites for just this purpose.
Segregation is the second main principle of projectile safety in the MRI environment. The first segregation is to keep unscreened people and equipment away from the entrance to the MRI scanner room. Again we bump up against a new Joint Commission requirement to restrict access. Like ferromagnetic detectors, access restrictions have been a part of the Guidelines building requirements, though the new Joint Commission standards will require this of all accredited MRI providers. The standard for this has been, and continues to be, the ACR’s Guidance Document on MR Safe Practices, and their call for a 4-zone sequence of screening and access controls.
The other component of segregation to reduce risks of projectile accidents is the ability to sequester or quarantine magnet-unsafe materials that are brought to the MRI unit. While the facility may have aluminum portable oxygen cylinders, or MR Conditional wheelchairs, patients coming in from the outside with their own oxygen, or being transported to the MRI unit from the ICU, will invariably bring with them equipment or devices that would be dangerous inside the MRI scanner room. These materials brought to the MRI suite need to be sequestered while the patient is switched to MRI-friendly versions of whatever support they need. Designating a storage space for unsafe materials brought to the MRI suite keeps them from getting comingled with equipment that lives in the suite, and makes it easier to collect patient belongings to make sure they leave with the patient they came with.
MRI safety, including projectile safety, is fundamentally an operational concern. But the fact that the daily responsibility falls to staff in no way diminishes the importance of the MRI facility designer. He / she must plan facilities that understand and accommodate not only the basic technical requirements of the MRI scanner, but also the operational and safety needs of a facility to support best practices.