Creation and Quantification Analysis of a Simulated SPECT Database Using the 4D-MOBY Phantom for Imaging Applications
T Kostou1, P Papadimitroulas1, G Loudos2, G C Kagadis1*, (1) University of Patras, Rion, Ahaia, Greece, (2) Technical Educational Institute of Athens, Aigaleo, Attiki, Greece.SU-E-CAMPUS-I-4 Sunday 3:00PM - 6:00PM Room: Exhibit Hall
Purpose: To develop a database of realistic animal SPECT simulations.Simulations were performed using a wholebody mouse model testing several realistic preclinical situations and compared against real small animal imaging acquisitions.
Methods: The GATE Monte Carlo toolkit was used for modeling a small animal SPECT system. The camera has a hexagonal parallel hole collimator and a ~1.6 mm spatial resolution.The 4D digital MOBY phantom was used in order to model mouse anatomy and activity distribution.Planar and SPECT scans for the biodistribution of the commonly used 99mTc based radiopharmaceuticals (MIBI, MDP and HMPAO) were modeled. Resulting simulated data were reconstructed using the QSPECT opensource software for SPECT reconstruction with a 10% energy window.
Results: Simulations were executed in the GateLab grid resulting to: a) MDP bone scan biodistribution (anterior posterior planar images), b) Whole body mouse Sestamibi biodistribution, c) 99mTc HMPAO (whole body scan), d) 2 scans for HMPAO biokinetics within the brain (mouse and rat), and e) 99mTc radiolabled magnetic nanoparticles imaging with the MOBY phantom (the activity distribution was extracted from real data). Quantitative analysis was performed in several regions of interest. Simulated results were compared against real data and theoretical values available in the literature.The HMPAO brain biokinetics of both the mouse and rat brains were compared in order to investigate the impact of the brain size on detecting various brain structures.In the mouse model the brain was observed as a single entity, while in the case of the rat brain model structures were distinguished.
Conclusion: GATE provides precise physics modeling based on the Geant4 code, while the 4D MOBY phantom can produce realistic imaging data, against which other imaging systems, reconstruction and correction techniques can be compared and standardized.To our knowledge this is the first small animal SPECT database with corresponding imaging data of realistic preclinical situations.