Intercept Pillar

Special report: An eye on MRI safety

October 16, 2013
by Carol Ko, Staff Writer
The oft-cited death of six-year old-Michael Colombini in 2001 due to an oxygen tank being brought into the MRI room has been the go-to example for people demanding better safety protocols around the machines. And the accident did bring safety to the forefront, with awareness causing a temporary dip in MRI-related accidents.

But now, 12 years later, the number of recorded accidents is steadily climbing every year, rising over 500 percent from 2000 to 2009. Granted, MRI accidents are still rare compared to the number of MRI scans performed each year, but the trend is still worrisome, especially given that hospitals notoriously underreport such accidents and the actual number could be much higher.

Experts say that this trend is unlikely to change without a significant shift in how everyone in the chain of command — from accrediting organizations down to technologists — view and enforce MRI safety standards.

The magnetic field created by the MRI magnet makes the MRI room a potentially dangerous place. Mop buckets, vacuum cleaners, stretchers and other common objects shuttled around hospitals could become lethal projectiles when brought too close to the magnet.

In theory, people entering an MRI room are supposed to go through a formal screening process to prevent metal objects or unauthorized individuals from entering the suite. This safety measure is especially crucial for patients with devices in their bodies containing metal — those with pacemakers, for example.

In practice, however, such processes break down.

Accidents that have the potential to be fatal are unnervingly common. “We had a report last week in the southeastern USA where we had a 78 year- old-woman with a .38 caliber entering an MRI room,” says Dennis Cook, president of MRI safety device firm Metrasens. “Clearly this should not be happening,” he adds.

So who’s accountable for these missed steps? The short answer: everybody.

Case closed
First and foremost, MRI safety suffers from a lack of reliable data, both because hospital accidents in general, and MRI accidents in particular, are underreported.

Fear of court liability among hospitals for reporting safety accidents has fostered a culture in which transparency is optional, and certain accidents never make it to the headlines due to gag orders. Cook says, “One particular expert witness I work with has dealt with many oxygen cylinder accidents, and they never go to court.”

Tobias Gilk

Create To get a better understanding of the numbers involved, Tobias Gilk, president of Mednovus, an MRI safety device firm, and renowned MRI expert Dr. Emanuel Kanal, professor of radiology at the University of Pittsburgh, compared data from Pennsylvania, which has mandatory accident reporting laws, against the national database of reported accidents.

They weren’t surprised to find that Pennsylvania’s reports made up 90 percent of the number in the FDA database. “It’s an illustration of just how abysmal the reporting is at the federal level,” says Gilk.

They formed a mathematical model to extrapolate what the true number of accidents might look like, estimating that there were 7,600 adverse events at a national level — and the FDA database is about 2 percent of that number.

Moreover, the FDA reporting guidelines for providers further confuse the issue, since the list of possible causes behind these accidents, which includes device failure or malfunction, presumes that there must be a problem in the labeling or design of the equipment to cause the injury. But in almost all the injuries in MR, the machine is functioning perfectly — it’s the environment that’s the problem. “So some hospitals ask, ‘do we really have to report, because the machine was functioning properly the way it was supposed to?’ ” says Gilk.

Zoning out
Some of the obstacles to MRI safety may be built right into the room itself.

According to experts, many MRI suites are laid out in such a way that technologists do not have a direct line of vision from their control console to the door to monitor the people going in and out of the room.

Some steps are being taken to remedy this problem for buildings in the future. In 2010, an influential building code guideline for hospitals and other providers cited by the Joint Commission and jointly supported by the U.S. Department of Health and Human Services (HHS) and the American Society for Healthcare Engineering (ASHE) released an update that included several MRI safety elements for the first time.

Though the HHS supports the code’s development, following the guidelines are voluntary, not a federal requirement. Even so, a majority of states reference it as a state licensure standard, with some exceptions — a few states, including California, Texas, and Missouri, have their own self-written building code guidelines. To date, 25 U.S. states have adopted this new building code.

The new requirements under the code include guidelines like use of ferromagnetic detection systems during the screening process, provisions for protection against cryogen leaks from MRI scanners, and making sure technologists have a direct line of sight in the MRI suite.

“The gist is as you get closer to the MRI scanning room, there should be increasing levels of supervision by MRI trained personnel and access control,” says Gilk.

“It’s amazing how many MRI suites were not designed properly for that,” says Geoffrey West, president of West Physics Consulting.

Another common structural problem West sees is doors that open inward into the room. “A door should never open inward, it should open outward, so that if the magnet quenches, the room doesn’t pressurize and prevent you from opening the door,” he explains.

Though the building code helps mitigate some of the issues around MRI safety, other issues require that operational protocols and standards be enforced within the provider’s department. And for that to happen, MRI suites would need accreditation standards.

There’s just one problem: none of the accrediting organizations within this modality have specific standards that prevent the most common MRI accidents from occurring. They all have recommendations to help mitigate risk, but they’re not built into the criteria for accreditation.

According to Gilk, it’s a matter of conflict of interest, since accrediting organizations rely on subscriber memberships from providers to keep alive.

“The unspoken concern is, if I’m head of an accrediting organization and I say let’s implement specific accreditation criteria, we will be increasing the burden on our providers,” he says. In other words, there’s widespread fear that such a move would drive dues-paying subscribers into one of the competing organizations.

“There’s a built-in disincentive to take on these standards, which is tragic because we know exactly how these patients are getting injured and we know what the effective preventions are,” says Gilk.

All that said, incremental steps toward change are on the way.

In August of this year, the Joint Commission released draft revisions on diagnostic imaging accreditation requirements that include new safety measures for hospitals using MRI.

But what’s most interesting about the draft is what it leaves off. Last year, we reported that Joint Commission surveyors were beginning to ask for documents verifying MR safety training among technologists along with requiring zone signs.

Curiously enough, neither of those criteria was included in the newly released draft revisions. Instead, the document stresses more stringent restrictions and supervision on access to MRI rooms by MRI-trained staff, and a separate room preceding the MRI suite for everyone not screened by staff — all of which essentially rephrases the ACR fourzone principle widely cited by MRI safety advocates.

The zone signage requirements may have been counterproductive to safety when applied to MRI suites that were not built with those zones in mind. On the other hand, experts agree that verification of safety training would have been a good addition to the document.

“Yes, it is a good first step to address the lack of standards in the industry, but in all honesty it wasn’t much more than a toe in the pool,” says Mednovus’s Gilk.