Wave-propagation simulation and dark-field computed tomography imaging study to elucidate the contrast-loss problem in X-ray diffraction-based transcranial brain imaging

It is crucial to overcome the skull-based contrast loss of cerebral structures in the development of high-resolution X-ray phase-contrast transcranial brain imaging. The present study aimed to determine the consequence of microporous skull-based scattering and its correlation with the contrast loss in a dark-field imaging-computed tomography transcranial brain imaging setup and to suggest methods for visualizing interior structures in analyzer-based X-ray transcranial brain CT imaging. Virtual-skull brain phantoms that mimic the microporous structure of the skull and internal structures including gray/white matter, glioma edema, and the central necrosis of glioma were prepared for wave-propagation simulation of dark-field computed tomography imaging. Reconstruction of refraction angle images and sinogram analysis of angle deviation showed microporous skull-mediated increases in the right-left angle mismatch and out-of-range values in curve fitting with a rocking curve, which was correlated with the contra...