X-ray Fluorescence Computed Tomography with a Compton Camera for a Clinical Application

XFCT is a promising new molecular imaging modality which is able to measure non-radioactive tracer molecules even in deep tissues. Unrestricted spatial resolution imaging with pencil beam x-ray excitation is possible but cannot be translated easily to clinical applications as scanning times are at least several hours. The spatial information accessed with Compton cameras (CCs) overcomes this drawback as fan or cone-beams can boost the measurement process. The spatial resolution and sensitivity performance of this new approach are studied on the basis of Monte-Carlo simulations. The results show that molecular sensitivities of 560 pM 1(-1) are accessible at 30 mGy for the demonstrated lung scan scenario and FWHM below 6 mm for lesion diameters of 1 mm. The scanning time was reduced by a factor of 45 for the given example.