FDA Gives Green Light to Simultaneous PET/MRI System

Sandra Yin

June 10, 2011

June 10, 2011 — The US Food and Drug Administration (FDA) has cleared for marketing the Siemens Biograph mMR system, which can simultaneously run a positron emission tomography (PET) scan and a magnetic resonance imaging (MRI) scan.

According to Siemens, the system is the world's only fully integrated whole-body molecular MR system with simultaneous MRI and PET data acquisition technology.

Siemens Biograph mMR system

Until now, devices have allowed physicians to use PET and computed tomography (CT) to image the body. What sets the new system apart is simultaneous MR/PET imaging, lower radiation doses, and better soft tissue contrast.

While an MRI scan provides details of organs, soft tissues, bone, and other body structures, a PET scan will simultaneously go further to explore the human body at the level of cellular activity and metabolism.

News of the system's 510(k) clearance will allow clinical researchers to venture further out into the frontier.

"This is very exciting news, particularly for the cancer imaging research community," said Savannah Partridge, PhD, a research assistant professor from the Department of Radiology at the University of Washington in Seattle.

"A combined PET-MR system will enable us to obtain complementary information on tumor metabolism by PET and tumor morphology and vascularity by MRI in a single examination," Dr. Partridge explained. "Both of these modalities have been shown to enable early accurate prediction of a patient's response to treatment, and the combination is likely to provide further advancements for individualizing patient therapies."

What is more, Dr. Partridge noted, MRI is better than CT at showing detailed anatomical information without the use of ionizing radiation, which becomes very important for repeated scanning to monitor individuals undergoing treatment.

The FDA cleared the Siemens system based on bench tests that compared the device with a preexisting PET/CT device.

The Siemens Biograph mMR system has already been installed at customer sites for clinical research, including Massachusetts General Hospital in Boston.


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