Cita:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, vol. 648, suplement 1, 21 august 2011. Pp. S172-S175
ISSN:
0168-9002
DOI:
10.1016/j.nima.2010.12.041
Agradecimientos:
This work has been supported by the MEC (FPA2007 62216), the UCM (Grupos UCM, 910059), the CPAN (Consolider Ingenio 2010) CSPD 2007 00042, the RECAVA RETIC network, ARTEMIS S2009/ DPI 1802, the European Regional Development and ENTEPRASE grant, PSE 300000 2009 5 and the Ministerio de Ciencia e Innovación, Spanish Government.
Positron range limits the spatial resolution of PET images and has a different effect for different isotopes
and positron propagationmaterials. Therefore it is important to consider it during image reconstruction,
in order to obtain optimal image quality. PoPositron range limits the spatial resolution of PET images and has a different effect for different isotopes
and positron propagationmaterials. Therefore it is important to consider it during image reconstruction,
in order to obtain optimal image quality. Positron range distributions for most common isotopes used in
PET in different materials were computed using the Monte Carlo simulations with PeneloPET. The range
profiles were introduced into the 3D OSEM image reconstruction software FIRST and employed to blur the
image either in the forward projection or in the forward and backward projection. The blurring introduced
takes into account the different materials in which the positron propagates. Information on these
materials may be obtained, for instance, from a segmentation of a CT image. The results of introducing
positron blurring in both forward and backward projection operations was compared to using it only
during forward projection. Further, the effect of different shapes of positron range profile in the quality of
the reconstructed images with positron range correction was studied. For high positron energy isotopes,
the reconstructed images show significant improvement in spatial resolution when positron range is
taken into account during reconstruction, compared to reconstructions without positron range modeling.[+][-]
