Advanced radionuclide detection techniques for in vitro and in vivo animal imaging

This review of the different methodologies used for animal imaging with radioactive compounds presents the most recent approaches developed for both in vitro and in vivo studies. The choice of a detector for analysis of the spatial distribution of radionuclides deposited in biological tissues results in a trade-off between the size and nature of the region to study (in vitro or in vivo), the required spatial resolution and the penetrating characteristics of the ionizing radiation. Real time detectors are now available for quantitative imaging of 2D or 3D radioactive samples and offer either an increased dynamic range or a lowered sensitivity in comparison with film radioautography. For high resolution imaging, two specific techniques are proposed for applications to rodents. The usefulness of self-triggering intensified charge coupled device (STIC) is illustrated for in vitro localization in radiotoxicological studies of alpha-emitters. For in vivo techniques, the performance of positron emission tomography (PET) is discussed, as a promising method of molecular imaging of biological processes.