Integrated method of enhancing image quality for FPD-based cone-beam computed tomography

The main factors of impacting Cone-Beam Computed Tomography (CBCT) image quality and their causes were studied, and an integrated method of enhancing CBCT image quality was proposed according to the Digital Radiography (DR) imaging model. First, the original polychromatic X-ray was filtered into quasi-monochromatic X-ray by the filter plate of copper-tungsten alloy, in order to improve the quality of the original projection images. Then, the integrated artifact corrections for projection images were processed on the order of dark field correction, gain non-uniformity correction, scatter correction and beam hardening correction, to avoid the one-sidedness of only correcting a certain kind of artifact. Experimental results show that the method can almost eliminate the main artifacts of CBCT system and improve image clarity and signal to noise ratio.