The Jülich Experience With Simultaneous 3T MR-BrainPET: Methods and Technology

Building on the success of positron emission tomography (PET)/CT scanners, a hybrid imaging technology, combining PET with the versatile attributes of magnetic resonance imaging (MRI), has been in use for over ten years. At the Forschungszentrum Julich, one of the four prototypes available worldwide, combining a commercial 3T MRI with a newly developed BrainPET insert, was installed in 2008, allowing simultaneous data acquisition with PET and MRI. Here, we report on our ten-year-long experience of the methods and technology developed through this paper with numerous patients and volunteers. In the course of our research, a number of different radiotracers, such as [18F]Fluoroethyltyrosine, [11C]Flumazenil, [11C]Raclopride, and [15O]H2O, have been applied while simultaneously measuring several different MR sequences. The PET data obtained with the BrainPET has demonstrated higher image quality and superior resolution capability compared to the stand-alone PET scanner, ECAT Exact HR+. Furthermore, the simultaneous acquisition of MR images alongside BrainPET scans, using different sequences, showed an excellent quality without any relevant artifacts and provided useful complementary information. Our experiences with the hybrid 3T MR-BrainPET indicate a promising basis for further developments of this unique technique, allowing simultaneous brain imaging in a clinical setting.