Go grab yourself a cup of coffee before you continue… this is going to be a long (for me, anyway) rant.
Let’s start at the very beginning (“what a very good place to start”). Back in the 80’s, when GE was seeking FDA approval for their new-fangled ‘nuclear magnetic resonance’ scanner, they were keenly aware of the risks of things going flying into the giant magnet. It turns out to be extremely difficult to have a giant, super-powerful electromagnet (one that doesn’t have an on/off switch) that doesn’t draw in every conventional ferromagnetic wheelchair, oxygen tank, gurney, mop bucket, rolling cart, etc… that comes near.
In an effort to help identify these threats before they were brought into the room, the GE application to the FDA called for mandatory metal detectors for screening patients and equipment as a part of each and every MRI installation.
Well, it turns out that this well-intentioned gesture was not very practical. As sites that have foolheartedly ventured down this path can tell you, darn near everything that is brought to the MRI suite has metal in it. This means that darn near everything, including objects that are at no risk of flying into the MRI, will set off the conventional metal detector. If the objective is to find only those things that would like to go flying into the MRI scanner, your conventional ‘airport style’ metal detector is of no use.
In the 1980’s there weren’t alternative means of detecting only ferromagnetic materials (those that become magnetized and get drawn to the MRI scanner), so the GE requirement for metal detection atrophied to nothing, becoming a forgotten (well-intended) bad idea.
Fast-forward about 20 years. At this point MRI technology is ubiquitous at hospitals (those with at least a couple hundred beds) across the country. Estimates were that there were somewhere around 8,000 MRI scanners in the US, and that most of them were GE products.
Concurrent with the growth in numbers of MRI scanners were increases in the magnetic strength and improvements to the ‘active shielding’ systems. Each of these enhancements had the coincidental effect of increasing the forces that draw magnetic materials into the scanner. When coupled, these factors actually multiplied the attractive force applied to magnetic objects, meaning that the risks associated with magnetic-projectiles flying into MRI scanners increased dramatically as the imaging technology advanced.
There have been magnetic-projectile accidents that jeopardize patients and staff in the MRI suite as long as there have been MRI scanners. The overwhelming majority of these remain ‘under the radar’ of safety, regulatory and accreditation bodies. One event occurred in the summer of 2001, however, that exploded through the veil of embarrassment that typically keeps these types of accidents secret.
In 2001, a young boy was anesthetized for an MRI scan and required oxygen during the exam. When the wall-outlet O2 didn’t work, the anesthesiologist called for oxygen. The technologists administering the exam left the control room to try and fix the oxygen supply problem and, while they were out, a nurse entered and told the anesthesiologist that there were oxygen tanks right there in the control room. Immediately upon bringing one of the portable tanks into the MRI scanner room, the magnetic field of the MRI ‘grabbed’ the tank and pulled it into the center of the doughnut-shaped scanner, where it struck the boy.
That six-year-old boy, Michael Colombini, died from the injuries a couple days later.
Splashed across the media and throughout radiology journals & trade publications, this event reignited the interest in metal detectors, many of the lessons learned from the prior experiments with ‘airport style’ detectors having been forgotten.
“If only there was a metal detector that only alarmed on magnetic materials,” was a common refrain. In 2001, there wasn’t (at least not an effective commercial product for pre-MRI screening). Ever the ‘mother of invention,’ the necessity for a magnetic-projectile screening tool prompted several companies, including Mednovus, to develop ferromagnetic only detection systems.
These products started becoming commercially available just a few years after the 2001 Colombini tragedy, and initially struggled to differentiate themselves from the failed legacy of’ ‘airport style’ detectors. In the years since, however, ferromagnetic detectors have become viewed as a valuable tool for safety in the MRI suite.
Would GE have mandated ferromagnetic detection (instead of the ‘airport style’ metal detectors) with their FDA application if the products had been available 20 years ago? Since the stated intention was to prevent projectile accidents, it would seem logical that they would have. They’re not the only MRI manufacturer to have indicated that choice, either.
In a 2008 interview with the Israeli business publication, Globes, Walter Marzendorfer, CEO of Siemens Medical Systems’ MRI Business Unit, was quoted as saying, “[t]he main safety issue where MRI is involved is the fact that it is a magnet. Accidents happen when a doctor enters the MRI room with a scalpel in his pocket and bends over the patient. People forget. There must be metal detectors at the entrance to every room with a MRI device.”
It would seem that Siemens has exactly the same take on the necessity for projectile safety in the MRI environment that GE had, namely that there should be some form of automated screening. I’ll chalk-up the use of the term “metal detector,” instead of the projectile-specific screening provided by a ferromagnetic detector, to the multiple languages likely involved in ultimately arriving at an English text. Both GE and Siemens have stated the necessity for some form of automated projectile screening, but it doesn’t end with the equipment manufacturers.
GE and Siemens aren’t alone in the calls for some form of requisite screening for projectile risks…
- In 2007, the ACR Guidance Document for Safe MR Practices amended language from prior publications which recommended against ‘airport style’ detectors to include the explicit recommendation for using ferromagnetic detection systems.
- In 2008, the US Department of Veterans Affairs (VA) MRI Design Guide echoed this recommendation.
- In 2008, the Joint Commission’s Sentinel Event Alert #38 offered ferromagnetic detection systems as an example of a conformance tool for their objective of verified patient screening.
- In 2009, the American Society of Healthcare Engineering (ASHE) published a monograph entitled Designing and Engineering MRI Safety which explicitly called for ferromagnetic screening.
- In 2009, ECRI Institute published their Top-10 Medical Technology Hazards watch-list for 2010. On that list is MRI projectiles and among the ECRI Institute’s recommendations are ferromagnetic detection systems.
There are others, but you get the gist. The technology of the ferromagnetic detector answers the need for MRI projectile protection which was identified nearly 30 years ago. It fits precisely with the intention of GE’s original FDA application for approval of MRI as a clinical device, and with the much more recent statement by Siemens’ top MRI guy. It has been recommended by major institutional standards and both professional and accrediting bodies, so it must be a ‘done deal,’ right?
Unfortunately, there has been one missing element… a requirement for MRI projectile safety protections.
It turns out that ‘perfect fits’ with manufacturers’ intentions and a ‘who’s who’ list of recommending bodies wasn’t enough. Yes, there have been many adopters of ferromagnetic screening tools, but estimates are that most of the MRI providers in the US still don’t use ferromagnetic screening for people entering the MRI suite. If they’ve been waiting for a requirement, that wait is just about over.
42 of the 50 US states, the Joint Commission, and many, many other health regulatory bodies around the world, use the Guidelines for Design and Construction of Health Care Facilities, originally jointly produced by the American Institute of Architects (AIA) and the US department of Health and Human Services (HHS). With updates to the standard published every 3 to 4 years, Guidelines is, in effect, the building code that governs most licensed and accredited MRI providers in the US. The 2010 edition of Guidelines just came out last month.
In the 2010 edition, for the very first time, Guidelines includes MRI safety protection requirements in the design criteria. Here’s one excerpt from the new code:
2.2-22.214.171.124 Design configuration of the MRI suite
(1) Suites for MRI equipment shall be planned to conform to the four-zone screening and access control protocols identified in the American College of Radiology’s “Guidance Document for Safe MR Practices.”
(2) The layout shall include provisions for the following functions:
(a) Patient interviews and clinical screening
(b) Physical screening and changing areas (as indicated)
(c) Siting of ferromagnetic detection systems
(d) Access control
(e) Accommodation of site-specific clinical and operational requirements
That’s right, the inclusion of ferromagnetic detection systems is a requisite element of MRI suite design in the 2010 Guidelines!
Since the 2010 edition of Guidelines has only just been published, it hasn’t (as of this writing) yet been adopted by the various authorities that use Guidelines, but that’s only a question of time.
And while the Guidelines, as a building code, might only apply to new MRI facilities and newly-sited MRI equipment, it appears that this may be just the first requirement-domino to fall.
In 2006 (yes, four years ago), the ACR’s MR Safety Committee issued a formal request to the ACR’s MR Accreditation Committee, include the Safety Committee’s Guidance Document principles as requirements for MR site accreditation. The MR Accreditation Committee has agreed that it will do something relative to MR safety in the accreditation process, but has yet to specify what this will be. It makes sense to me that the ACR MR Accreditation Committee would (minimally) appropriate existing physical safety requirements put forward by other entities (preserving the ability to deflect criticism with, ‘it’s not our standard, it’s just one that many of our accredited providers will be held to by other agencies and we felt it prudent to include it in our accreditation standards to make sure that they weren’t otherwise caught unaware.”).
Similarly, the Joint Commission (TJC), having just received ‘deemed status’ and the ability to accredit advanced imaging providers (CT, MRI, PET) for the 2012 Medicare requirements, is purportedly working on imaging-specific patient safety standards. While TJC will adopt the 2010 Guidelines as their physical facility standard, that may also provide them with the ability to develop their own MR safety specific accreditation standards. I would expect to see a flurry of imaging-specific guidance and standards coming from TJC starting this summer / fall.
What does this all mean if you’re an MRI provider? One of the things it means is that if you don’t already have a ferromagnetic detection system, you should get one, and get it soon. Setting aside the ‘best practice’ standards, loss-reduction, safety improvement, and throughput benefits, ferromagnetic detectors will be requirements of accreditation and licensure.
If I can be of any assistance to you, navigating the new requirements or addressing questions about ferromagnetic detection, please do contact me.Tobias Gilk, President & MRI Safety Director Mednovus, Inc. Tobias.Gilk@Mednovus.com www.MEDNOVUS.com