Research Projects

The University of Manitoba PET Imaging Lab has many ongoing research projects focused on new technologies, both hardware and software, for advancing medical imaging. Currently active projects are described here.

MRI Compatible PET Insert for PET/MR Imaging of Small Animals

16 detector small animal PET insert prototype for PET/MRI imaging.Schematic of system geometry showing dual layer offset detector ring.

Together with our collaborators at UBC, TRIUMF and McGill University we have constructed a prototype MRI compatible PET insert for small animal PET/MRI imaging using a 7T MRI system. Development of this system has the following subprojects:

Detectors for High Resolution PET/MR Systems

Photograph of detector module showing dual-layer offset LYSO scintillator array coupled to a pair of SensL SPMArray4B SiPM detectors. The crystal pitch is 1.27 mm.Flood histogram image of the detector showing well resolved crystal elements.

Slow Control and Temperature Compensation of SiPM PET Detectors

We have designed and constructed a Detector Interface Board (shown above) and a slow control system to monitor and control the PET detector modules of our PET insert system and to act as an intermediary between the detectors and the OpenPET digitizer system.
The slow control software is a multi-client networked system. A client program was developed in the Python programming language to be run on the Raspberry Pi® computer on each Detector Interface Board. This client program is designed to communicate with a LabWindows™/CVI application on a PC over a TCP/IP network and provide the capability for the server application to control the functions of each board. The LabWindows™/CVI application accepts connections from the Python programs on each Detector Interface Board.

Data Acquisition Systems for PET Imaging

We are using the OpenPET platform (http://openpet.lbl.gov) for data acquisition. The OpenPET system is a reconfigurable, high resolution, scalable and user friendly electronic and software system for PET and SPECT imagers. This system can support any type of detectors and event word definitions. FPGAs are primarily used to control the electronic and provides a flexible way to modify the firmware and software for customized needs without changing the electronic circuitry. The University of Manitoba PET Imaging Lab is contributing to the firmware and software development for this system. Development platforms are VHDL, Verilog, C/C++ and Matlab.

Modeling of Light Transport in Scintillation Crystals

Image of 7 x 7 LSO crystal array modeled using GATE.Modeling optical photon transport in a pair of scintillator crystals using GATE.

Within a scintillation block detector, light sharing between scintillation elements can be important for locating the position of interaction for the 511 keV gamma ray. However the factors affecting light sharing and transport between crystals are not fully understood. Simulations using GATE, a Geant4 Monte Carlo simulation package, are being developed to better understand and model the underlying factors affecting light transport within scintillation crystals in PET block detectors. Physical measurements of light transport are also being designed with the aim to validate and improve the simulations accuracy.