According to the FDA, 2008 saw a 30 percent increase in the number of reported MRI accidents. In the four years following 2004, the FDA's MAUDE database catalogues a 270 percent increase in MRI accidents. But what may be even more troubling than the dramatic increase in reported accidents are the numbers that aren't included in the FDA's data.

The extreme power of the magnets used for MRI imaging (typically tens-of-thousands of times greater than our exposure to the Earth's own magnetic field) can readily 'pull' ferromagnetic materials to the scanner, sometimes with lethal results. These types of accidents, frequently referred to as 'projectile' or 'missile' accidents, are the most common MRI mishap and yet comprise a slim minority of the FDA's accident reports.

The failure to report projectile accidents is one reason why many experts believe that the FDA's data may represent only 1% of the actual number of MRI accidents that occur, suggesting that the frequency and variety of accidents is far greater than is widely believed by the industry.

Most MRI accidents, including missile events, are the sort of accidents that are frequently classified as 'never events.' These are negative outcomes, such as wrong-site surgeries, that could readily be avoided by adherence to contemporary best practices.

Effective screening of patients, visitors, and even staff, is of critical importance prior to allowing the individuals near the MRI scanner. This screening is composed of both a clinical screening, intended to root-out potential complications or contraindications for the MRI exam, such as pacemakers or intolerance for contrast agents, and a physical screening to help assure that ubiquitous ferromagnetic materials are not brought into the MRI scanner room.

The single revolution in pre-MRI screening, providing new protections above conventional verbal screening and medical record review, is the ferromagnetic detector. Whereas conventional 'airport style' metal detectors alarm on aluminum, titanium and other non-magnetic metals of which many appliance for the MRI suite are made, the new generation of ferromagnetic-only detectors alarm exclusively on those materials that are attracted to the immense magnetic field of the MRI scanner.

In the interest of enhancing MRI safety, ferromagnetic detection pre-screening systems have been recommended by MHRA, FDA, the Joint Commission, the ACR and other professional bodies. But the benefits to the MRI provider in reducing the likelihood of injurious accidents are not solely altruistic.

In 2008, the United States Department of Veterans Affairs published their average cost of a MRI projectile accident , exclusive of equipment downtime overhead costs, at $43,172 (€34,274) per incident. Providers that depend on per-procedure reimbursement would likely compound the VA's direct costs with significant additional costs associated with lost patient throughput.

While ferromagnetic detection products can substantially reduce the risks of projectile accidents when used appropriately, they should be viewed as an integral adjunct to thorough and conscientious conventional screening practices and not a replacement for traditional methods.

With the profound spike in MRI accident rates and the exorbitant costs of MRI system repair and downtime, there are coincident professional and financial imperatives to reduce the likelihood of adverse outcomes in the MRI environment. One solution that should be at the top of every MRI provider's list should be the ferromagnetic detector.

Tobias Gilk is the president and MRI Safety Director of MedNovus, a Leucadia, Calif.-based MRI safety products and consulting firm.