The BrainPET prototype (Siemens Healthineers) is a head insert designed to fit inside the 3T Siemens TIM Trio 60 cm whole-body MRI scanner. There are 32 detector cassettes that make up the BrainPET gantry, each consisting of six detector blocks. Each detector block consists of a 12×12 array of lutetium oxyorthosilicate (LSO) crystals (2.5×2.5×20 mm3) readout by a 3×3 array of Hamamatsu avalanche photodiodes (APDs, 5×5 mm2). The gantry physical inner and outer diameters are 35 and 60 cm, respectively. The transaxial and axial fields-of-view are 32 cm and 19.125 cm, respectively.
After the BrainPET was installed at the Martinos Center in May 2008, we worked very closely with the Siemens engineers to optimize its performance and improve the image quality. We have been using the BrainPET in a myriad of studies ranging from those aimed at investigating the mutual interference between the two devices and the performance of the PET camera, developing methods to use the information obtained from one device to improve the other modality, and performing proof-of-principle studies in small animal, non-human primates and humans.