Quantitative evaluation of scatter correction and attenuation correction in Shimadzu 3D PET scanner

3D continuous emission and spiral transmission scanning allows high-throughput whole-body PET studies with the use of two dedicated detectors for high-sensitivity emission and single transmission simultaneously. In order to reduce the scatter component in the emission data, we have implemented a hybrid scatter correction method based on dual energy window setting. This scatter correction method can reduce the increased scatter noise due not only to the object size but also to the activity distribution inside and outside the axial field of view (FOV). On the other hand, we have implemented the soft-tissue segmentation method for attenuation images in order to reduce the slight variance caused by transmission scatter and residual effects after emission contamination correction. In the present study, we evaluated the combined use of these two correction methods by comparing the reconstructed images obtained under various conditions such as different activity concentrations, object sizes, and external activity distributions. The combined use of hybrid scatter correction and soft-tissue segmentation attenuation correction provides quantitative images in experimental and clinical acquisition. (author)