Do scatter and random corrections affect the errors in kinetic parameters in dynamic PET?: a Monte Carlo study
2013 (English)In: 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), IEEE conference proceedings, 2013, , 4 p.Conference paper (Refereed)
Dynamic positron emission tomography (PET) data can be evaluated by compartmental models, yielding model specific kinetic parameters. For the parameters to be of quantitative use however, understanding and estimation of errors and uncertainties associated with them are crucial.
The aim in this study was to investigate the effects of the inclusion of scattered and random counts and their respective corrections on kinetic parameter errors.
The MC software GATE was used to simulate two dynamic PET scans of a phantom containing three regions; blood, tissue and a static background. The two sets of time-activity-curves (TACs) used were generated for a 2-tissue compartment model with preset parameter values (K1, k2, k3, k4 and Va). The PET data was reconstructed into 19 frames by both ordered-subset expectation maximization (OSEM) and 3D filtered back-projection with reprojection (3DFBPRP) with normalization and additional corrections (A=attenuation, R=random, S=scatter, C=correction): True counts (AC), true+random counts (ARC), true+scattered counts (ASC) and total counts (ARSC).
The results show that parameter estimates from true counts (AC), true+random counts (ARC), true+scattered counts (ASC) and total counts (ARSC) were not significantly different, with the exception of Va where the bias increased with added corrections. Thus, the inclusion of and correction for scattered and random counts did not affect the bias in parameter estimates K1, k2, k3, k4 and Ki. Uncorrected total counts (only AC) resulted in biases of hundreds or even thousands of percent, emphasizing the need for proper corrections. Reconstructions with 3DFBPRP resulted in overall 20-40% less biased estimates compared to OSEM.
Place, publisher, year, edition, pages
IEEE conference proceedings, 2013. , 4 p.
PET, dynamic PET, Monte Carlo, GATE, compartment model, scatter correction, random correction, FLT
Medical Image Processing
Research subject radiofysik
IdentifiersURN: urn:nbn:se:umu:diva-98415DOI: 10.1109/NSSMIC.2013.6829388ISI: 000347163501202ISBN: 978-1-4799-0534-8OAI: oai:DiVA.org:umu-98415DiVA: diva2:782688
60th IEEE Nuclear Science Symposium (NSS) / Medical Imaging Conference (MIC) / 20th International Workshop on Room-Temperature Semiconductor X-ray and Gamma-ray Detectors, Seoul, South Korea, Oct 27-Nov 02, 2013
FunderSwedish National Infrastructure for Computing (SNIC), 2013/1-234Swedish National Infrastructure for Computing (SNIC), HPC2N-2009-001