abstract book topim2 - European Society for Molecular Imaging (ESMI)

DUAL AND INNOVATIVE IMAGING MODALITIES
ULTRA RESOLUTION SPECT COMBINED WITH OTHER MODALITIES
Freek J. Beekman 1,2,3 , F. van der Have 2,3 B. Vastenhouw 2,3 , W. J. Branderhorst 2 , R.
Ramakers 2 , C. Ji 2
1 Delft University of Technology, Delft, The Netherlands
2 University Medical Centre Utrecht, Utrecht, The Netherlands
3 MILabs, Utrecht, The Netherlands
f.j.beekman@tudelft.nl
Aim: To develop an extremely user friendly and reliable SPECT system with
unsurpassed resolution that can be readily combined with other imaging modalities.
Methods: We constructed a new rodent SPECT system (U-SPECT-II [1]) and a CT
scanner (U-CT) with dedicated multi-modal animal beds and registration software for
localized sub–half-millimeter total-body SPECT. Three optical cameras and a
dedicated interface are fully integrated with U-SPECT to allow pre-selection of the
field-of-view without adding any dose to the animal. This facilitates focusing the
pinholes, thereby maximizing sensitivity for the task at hand. Furthermore, the optical
cameras allow for unique registration possibilities, in particular with images from
independent optical modalities.
Results: SPECT resolutions better than 0.35mm where obtained for Tc-99m.
Resolutions with In-111 and I-125 were barely degraded, compared to Tc-99m.
Image registration of SPECT with CT was better than 0.2 mm.
Discussion: U-SPECT-II and combined U-SPECT-II/U-CT can be used for novel
applications in the study of dynamic biologic systems and pharmaceuticals at the
suborgan level. Discrimination of molecule concentrations between adjacent volumes
of about 0.04 µL in mice and 0.5 µL in rats with U-SPECT-II is readily possible.
Accurate anatomical localization can be done efficiently and cost-effectively with
independent modalities such as CT or MRI. For imaging small animals separate
systems offer unique advantages over integrated devices [2].
References:
[1] F. van der Have et al. U-SPECT-II: An Ultra-High-Resolution Device for Molecular
Small-Animal Imaging, J. Nucl. Med. 2009
[2] F.J. Beekman and B.F. Hutton “Multi-modality imaging on track”, Eur. J. Nucl.
Med. Mol. Im, 2007
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