Patient motion during MRI proves to be costly conundrum

When a patient moves during an MRI, it can mean having to redo the scan. Repeated scans take time, and tied up scanners can affect a hospital’s bottom line. Just how costly is patient motion? A recent study from Harborview Medical Center in Seattle pegged the potential cost of motion artifacts at $115,000 per scanner per year.

“These costs may affect much of the global MR community, reducing resource efficiency and the quality of patient care,” wrote authors Jalal B. Andre, MD, of the University of Washington in Seattle, and colleagues. Their findings were published online in the Journal of the American College of Radiology.

Motion artifacts such as blurring or ring artifacts can affect interpretation, and advanced MR techniques are particularly at risk as they rely on high spatial resolution and greater sequence complexity, noted Andre and colleagues. Despite these challenges, the authors were surprised that few studies have looked at the prevalence or impact of motion artifacts in clinical MR exams.

To get an estimate of the significance of this issue, Andre and colleagues retrospectively reviewed one randomly selected week’s work of MR exams conducted at Harborview Medical Center. The sample came from April 2014 and included scans from three different scanners. A pair of blinded neuroradiologists visually reviewed the scans and used a five-tier scale to measure the presence of motion artifacts, from “none” to “severe.”

Across 192 completed clinical exams in the sample, nearly one-in-five (19.8 percent) had to be repeated due to motion artifacts.

Once broken down by patient disposition, the authors reported that 7.5 percent of outpatient exams and 29.4 percent of inpatient and/or emergency department exams had significant motion artifacts. They suggested this difference stems from the fact that outpatients are presumably healthier and in less acute distress than inpatients.

After reviewing institutional data to determine the cost of lost scanner time, Andre and colleagues determined the potential cost to the hospital was $592 per hour in lost revenue due to motion artifacts, equating to an average cost of approximately $115,000 per scanner per year. The authors did note that precise estimates of costs are difficult and that they used a simplified, averaged-cost approach. The one-week sample of scans is a limitation, as there could be significant week-to-week variance. Results across the country could vary widely as well, owing to geographic variability in reimbursement, payer mix, practice patterns, and other factors.

Still, the potential costs of MRI motion artifacts are likely to be significant anywhere, and the authors suggested greater attention should be paid to this problem. Software that can correct for motion would be valuable, as would efforts to reduce sequence acquisition time.

“The results of this study suggest that the goal of reducing motion artifacts, and the related image degradation, represents an opportunity to improve efficiency, reduce costs, and improve imaging services,” wrote Andre and colleagues.