PETイメージングの最前線 Recent Advances in PET Imaging Technology

Positron emission tomography (PET) provides qualitative and quantitative information about the distribution over space and time of a given radiotracer within the body. Due to the ability to produce fused PET/CT images, combined PET/CT scanners have been rapidly replacing dedicated PET cameras in the market. A new technology named SYNETRAC has led to a new type of whole-body PET/CT that can perform CT scanning only for cancer localized areas previously determined by whole-body PET scanning. This PET/CT can significantly reduce radiation dose without compromising patient throughput. With requirement of both high sensitivity and high spatial resolution, organ-specific PET with depth-of-interaction (DOI) detector system is now under development. The first development target is high-resolution positron emission mammography (PEM) for improving sensitivity and specificity of breast cancer diagnosis. The DOI detector technology has also be applied to small animal PET for laboratory rodents used in basic medical research and drug discovery. The scanner consisting of DOI detector modules with a large axial extent provides significant advantages in fine-structure imaging and quantitative kinetics measurements. We believe that these new PET technologies will be widely used for early diagnosis, effective treatment assessment, and drug discovery.