A Novel Approach for Reducing Dental Filling Artifact in CT-Based Attenuation Correction of PET Data

Abstract — Reliable attenuation correction methods in PET require accurate determination of the attenuation map (µmap), which represents the spatial distribution of linear attenuation coefficients (LACs) at 511 keV for the region under study. Since CT image pixel intensities are directly related to the LAC of the corresponding tissue calculated from the effective CT energy, the µmap at 511 keV can be directly generated from the CT images. The presence of high density dental fillings material in head and neck CT imaging is known to generate strong streak artifacts in the µmap which will likely propagate to the resulting PET images during CT-based attenuation correction (CATC). The purpose of this work is to develop a fast approach for reduction of dental filling artifacts in the generated µmap. Currently available sinogram based metal artifact reduction (MAR) algorithms are based o