Since the multi-tracer positron emission tomography (PET) technology will increase the total dose of tracers, it is necessary to study the low-dose multi-tracer PET technology. In this paper, we proposed a model based on attention mechanism to estimate the standard-dose single-tracer sinogram from the low-dose dual-tracer sinogram, that is, to achieve both standard-dose estimation and dual-tracer signal separation in sinogram domain. Both the spatial attention and channel attention were implemented. We cascaded the FBP-Net for reconstruction after the proposed model, and verified the proposed method in simulation experiment and rat experiment. At the same time, we compared the results of dual-tracer PET signal separation in sinogram domain and activity map domain. The results prove the effectiveness of the proposed method in the problem of low-dose dual-tracer PET image reconstruction, and also show that signal separation in sinogram domain is more effective than separation in activity map domain.
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