Development of γ-ray emission imaging

Noninvasive imaging, particularly in small animals, has become important for the development of novel drugs and therapies. As a new imaging modality, we tried concurrent multi-probe tomography, using a collimatorless γ-ray emission imaging system consisting of a Compton camera. The camera comprises a pair of planar position-sensitive germanium detectors. As the system can detect a broad range of γ-rays up to 2 MeV with high-energy resolution, it is suitable for the tomographic imaging of a multitracer that contains multiple radioactive nuclides, each of which can tag separate biochemical processes. Here we show an example of biological applications - imaging of a tumor-bearing mouse - that illustrates the essence of concurrent multi-probe tomography. (author)