MRI safety Archives - The Imaging Wire

Radiology has a renewed focus on MRI safety following the tragic death of a New York man in an MRI accident last month. With that in mind, a new JACR study looks at adverse MRI events caused by an uncommon but still important phenomenon: retained bullet fragments in patients getting scans.

MRI is radiology’s most powerful modality, but its strong magnetic fields can be hazardous – and on extremely rare occasions even fatal – for both patients and medical personnel.

Patients are supposed to be screened for metallic implants, jewelry, and other contraindications, but how often do providers know to ask about retained bullet fragments?

Having a retained bullet fragment on its own isn’t a contraindication for MRI, but providers do need to know where fragments are located and how large they are.

If pre-scan screening discovers a patient with a retained fragment, they typically receive X-rays of the involved area to determine location and size – scans should be aborted if the fragment is in a solid organ or within 5 mm of an important artery or vein.

If all these steps are taken and the scan goes ahead, how often do adverse MRI events occur?

Researchers reviewed 6.1k X-ray reports that contained the terms “bullet” or “shrapnel” over 13 years, finding 284 patients who got an MRI scan after a retained fragment was found on radiography.

They found…

Only four patients (1.8%) experienced symptoms during MRI scans.
Each of the exams was terminated early due to patient discomfort, with three patients reporting burning and one general discomfort.
None of the symptomatic exams had the bullet in the MRI field of view.
No serious injury and no follow-up care was required.

The Takeaway

The new findings are encouraging by showing that with careful patient screening and monitoring, MRI scans can be performed on patients with retained bullet fragments. But as always, MRI operators must remain vigilant and adhere to published MRI safety guidelines.

A tragic MRI accident in Long Island, New York, has turned deadly. A man who was pulled into a mobile MRI scanner by a heavy chain he was wearing died of his injuries.

Keith McAllister was waiting outside a mobile MRI trailer operated by Nassau Open MRI on Long Island as his wife received a knee scan.

McAllister was wearing a weight-training chain around his neck that weighed some 20 pounds.

When he entered the trailer to help his wife get off the scanner table, the system’s powerful 1.5T magnetic field drew him against the magnet. It took staff an hour to free him.

McAllister was transported with critical injuries to a local hospital, where he died of a heart attack the next day.

Investigators are still looking into the details of the episode, but it underscores the shortcomings in how MRI safety is regulated in the U.S., where fatal MRI accidents are extremely rare but still do occur.

That’s according to MRI safety expert Tobias Gilk, vice president at architectural firm Radiology Planning and founder of Gilk Radiology Consultants, who spoke to The Imaging Wire about the accident.

The U.S. has some of the most comprehensive and sophisticated guidelines on MRI safety, encapsulated in the ACR Manual on MR Safety.

What’s more, the radiology community including ACR, ISMRM, ASRT, and others are currently observing their annual MR Safety Week to promote safe MRI scanning – an event that started just a few days after McAllister died.

But despite the great leaps in knowledge about MRI safety, Gilk believes that keeping patients safe is complicated by the exponential growth in the modality’s complexity, while actual enforcement of safety standards is lacking.

Many state health departments don’t even address MRI safety as they focus more aggressively on regulating ionizing imaging modalities like CT and X-ray, and healthcare certification bodies like the Joint Commission lack enforcement teeth.

Instead, MRI safety often becomes the responsibility of technologists who frequently must juggle multiple tasks as they manage both patients and scanner operations.

This can be particularly challenging in mobile MRI coaches, often staffed by a single MRI technologist where the only barrier between the outside world and the scanning environment is just a single – often unlocked – door.

The Takeaway

The tragic death of Keith McAllister in a mobile MRI trailer shows that all the guidelines and safety events in the world won’t keep patients safe unless accompanied by stronger enforcement of the knowledge the radiology community already has. We can do better.

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