Agradecimientos:
This work has been partially funded by projects TEC2004-07052-C02 of Ministerio de Educación y Ciencia and CD-TEAM, program CENIT, Ministerio de Industria, Spain. Part of the computations of this work were done at the '`High capacity cluster for physical
techniques'' of the Faculty for Physical Sciences of the UCM, funded in part by the UE under the FEDER program and in part by the UCM.
The potential of PET imaging for pre-clinical
studies will be fully realized only if repeatable, reliable and accurate quantitative analysis can be performed. The
characteristic blurring of PET images due to positron range and non co-linearity, as well as raThe potential of PET imaging for pre-clinical
studies will be fully realized only if repeatable, reliable and accurate quantitative analysis can be performed. The
characteristic blurring of PET images due to positron range and non co-linearity, as well as random, pile-up and scatter
contributions, that may be significant for fully 3D PET acquisitions of small animal, make it difficult their quantitative analysis. In this work specific activity versus specific counts in the image calibration curves for 3D-OSEM
reconstructions from a commercially available small animal PET scanner are determined. Both linear and non-linear
calibration curves are compared and the effect of corrections for random and scatter contributions are studied. To assess the improvement in the calibration
procedure when scatter and random corrections are considered, actual data from a rat tumor pre- and postcancer
therapy are analyzed. The results show that
correcting for random and scatter corrections can increase the sensitivity of PET images to changes in the biological
response of tumors by more than 15%, compared to uncorrected reconstructions.[+][-]
Nota:
Proceeding of: 2007 IEEE Nuclear Science Symposium Conference Record (NSS'07), Honolulu, Hawaii, USA, Oct. 27 - Nov. 3, 2007
