Speaker
Description
Positron Emission Tomography (PET) is one of the leading methodologies in medical imaging for cancer diagnosis, but PET scanners present some limitations in terms of cost and performance. In recent years, Time-of-Flight PET (ToF-PET) significantly improved image reconstruction by adding to the energy used in standard PET machines, the time of arrival information of the two $511\:keV$ annihilation photons. The PETVision project aims to use breakthrough findings in the ToF-PET research field to develop a highly sensitive, fully modular and cost-accessible scanner to achieve $75\:ps$ FWHM Coincidence Time Resolution (CTR). This challenge requires a revolutionary technology change in terms of photodetectors, readout electronics and integration methodology to push the limit of the timing performance.
In controlled laboratory conditions, a CTR of $96\:ps$ FWHM has been achieved by using FBK NUV-HD-MT SiPMs $3\times3\:mm^2$, $40\:\mu m$ cell size with metal masking outside the active area (M0) coupled with a $2\:mm \times 2\:mm \times 20\:mm$ co-doped LYSO:Ce:Ca crystal. A $60\:ps$ FWHM CTR was achieved using the same device on a $2\:mm \times 2\:mm \times 3\:mm$ crystal. These measurements have been performed using high-frequency readout electronics with high power consumption; thus, they are not scalable to multi-channel systems and are impractical for realistically sized imaging systems.
Therefore, much effort is being made to develop a novel, custom front-end System-on-Chip (SoC) ASIC to be coupled with these next-generation timing-optimized SiPMs and ensure high-timing performance. Preliminary results using the FastIC+ ASIC, developed at ICCUB and CERN, are extremely promising, showing a CTR of $89\:ps$ FWHM with a $3\:mm$ co-doped LYSO:Ce:Ca crystal using a FBK NUV-HD-MT $3\times3\:mm^2$ $50\:\mu m$ M0.
Thanks to the collaboration of several universities, research centres and industries, PETVision is set to make significant advancements in detector design, photo-sensor and front-end electronics by developing an affordable, fast and precise ToF-PET scanner, enabling early cancer detection and therapy monitoring, opening the way for personalized medicine.
