A device that simultaneously performs a PET (positron emission tomography) scan and an MRI (magnetic resonance imaging) scan, called the Siemens Biograph mMR system, has been cleared by the FDA (US Food and Drug Administration).

A PET scan sees how internal parts of the body are functioning – it tracks metabolism, movement. A radioactive chemical tracer is injected into the patient’s bloodstream. When inside, the tracer goes to areas inside the body that use the natural chemical. For example, fluorodeoxyglucose (FDG) is tagged to glucose to make a radiotracer. Cancers use glucose differently, so FDG can show up cancers.

An MRI machine uses radio waves and a magnetic field to create detailed images of internal parts of the body, such as soft tissues, organs and bones.

Siemens Biograph mMR system can do simultaneous imaging, it can show up increased soft tissue contrast, and uses less radiation than a PET or CT (computer tomography) scan, the FDA informs.

Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostic Device Evaluation and Safety in the FDA’s Center for Devices and Radiological Health, said:

“The Siemens PET/MRI system allows two tests to run simultaneously without having to move the patient to a different scanning system. Minimizing changes in a patient’s position between tests allows physicians to compare images more easily and helps them get the most accurate information possible.”

Rather than using CT to produce detailed pictures of internal parts of the body, the Siemens PET/MRI system uses MRI, which produces greater detail in virtually all the body’s internal structures than a CT does. MRI images are based mainly on water concentrations in the body, while the CT uses X-rays. With this new device the health care professional will have valuable additional data about a patient’s condition.

With the Biograph mMR system, the patient is exposed to much lower radiation levels compared to a PET/CT system. Patients who have to undergo several scans will benefit, as well as other sensitive populations, such as young children.

The FDA evaluated the results of bench tests that compared the Biograph mMR system with a standard PET/CT device.

Anyone who requires diagnostic PET or MRI imaging is a potential candidate for the Siemens Biograph mMR system.

The FDA added:

“However, people with pacemakers, defibrillators or other implanted electronic devices should not be scanned with the Biograph mMR system unless those devices are specifically indicated for use in the MRI environment, because the strong magnetic fields of the MRI system may interfere with those devices.”

In a communique, Siemens Medical Solutions wrote:

“MR and PET have become an established part of everyday healthcare routines and have proven themselves to be valuable clinical diagnostic tools. The integration of these two technologies into a single system capable of simultaneous acquisition brings the potential to revolutionize the diagnosis of many conditions. Initial research suggests that with this system, Molecular MR can scan the entire body in as little as 30 minutes for the combined exams, compared to one hour or more for sequential MR and PET examinations.”

Siemens said that if you look at it from the patient’s point of view, this new device means one exam instead of two. The advantage for the medical center is that it is only one system; it takes up less space, there is just one investment, which in the longer-run will give significant economic benefits.

A Siemen’s spokesperson said that this device opens new horizons with respect to finding diseases earlier. It allows for a faster understanding during follow up on how treatment is working. In the areas of neurology and oncology, and later on cardiology, it will allow for improved diagnostics.

This YouTube video below was released before FDA approval:

The Biograph mMR system is made by Siemens Medical Solutions, Pennsylvania, USA. It is part of Siemens, the German engineering company.

Written by Christian Nordqvist