Abstract: An attenuation correction method and device for an image in a PET system. The method includes: acquiring transmission scanning sinogram data from a PET apparatus; reconstructing the transmission scanning sinogram data with Bayesian model-based Ordered Subset Expectation Maximization (OSEM-B) algorithm and Filtered Back Projection (FBP) algorithm, to obtain an OSEM-B attenuation image and a first FBP attenuation image respectively; performing a weighted calculation on the OSEM-B attenuation image and the first FBP attenuation image to obtain an effective attenuation image; and performing attenuation correction on emission scanning sinogram data from the PET apparatus by using an attenuation sinogram generated based on the effective attenuation image.

Abstract: A multimodality imaging system, comprising: a first imaging system for forming a first image; a second imaging system for forming a second image; and a rotating device on which the first imaging system and the second imaging system are fixed so that the first imaging system and the second imaging system are selectively rotated to a scanning position.