Development of an in-situ radiotracer concentration measurement system using compact pixilated LuAG-APD Gamma-ray detector module

Kinetic modeling and dynamic acquisition along with blood sampling is the most accurate method for the PET quantitative studies. However, the blood sampling is very inconvenient and painful for the patients, handling of radioactive samples is risky to workers and time consuming as well as less efficient to imaging centers. Various approaches are proposed to reduce the exposure to workers and number of blood samples to comfort the patient but no one fulfills all the requirements. Recently a novel compact Time over Threshold (ToT) based Pr:LuAG-APD animal PET tomograph was developed in our laboratory which has 10% energy resolution, 4.2ns time resolution and 1.76mm spatial resolution when using ²²Na columnar source. The obtained value of spatial resolution shows much promise for imaging the blood vascular of diameter 2.3-2.4mm. Spatial resolution has prime importance in blood vascular image formation whereas, the sensitivity of system determines the measurement time which is another important parameter for clinical applications. We are presenting simulation results regarding the sensitivity of the developed small animal PET system.