Image reconstruction based on Fourier-rebinning for a novel high resolution ClearPET Neuro scanner

At present a high-resolution PET scanner (ClearPET Neuro) is constructed at the Research Centre Jülich. While human PET systems have a spatial resolution of 5-7 mm, high resolution PET needs a resolution of < 2 mm and a high sensitivity which is achieved e.g. by taking data in fully 3D mode. The Fourier-Rebinning algorithm (FORE) is a procedure that sorts the 3D data into a 2D data set. The 3D image is then recovered by applying a 2D reconstruction method to each slice, such as filtered back projection. FORE is approximate, but allows an efficient implementation, based on the 2D Fourier transformation of the data [M. Defrise, et al., Exact and approximate rebinning algorithms for 3-D PET Data, IEEE Trans. Med. Imag. 16 (1997) 145-158] and speeds up the reconstruction time significantly.